HomeMy WebLinkAboutHMP 09-05; LAKE CALAVERA TRAILS MASTER PLAN; FINAL WETLAND HABITAT MITIGATION AND MONITORING PLAN FOR THE LCTMP BOARDWALK IMPROVEMENT PROJECT; 2012-08-01LAKE CALAVERA TRAILS MASTER PLAN
BOARDWALK IMPROVEMENT PROJECT
FINAL WETLAND HABITAT MITIGATION AND
MONITORING PLAN
Prepared for:
City of Carlsbad
Parks and Recreation Department
799 Pine Ave. Suite 200
Carlsbad, California 92008
Contact Liz Ketabian
Prepared by:
DUDEK
605 Third Street
Encinitas, California 92024
Contact: John Minchin
Landscape Architect #2225
Habitat Restoration Specialist
AUGUST 2012
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Final Wetland Habitat Mitigation and Monitoring Plan
TABLE OF CONTENTS
Section Page No.
EXECUTIVE SUMMARY .......................................................................................................... V
1.0 DESCRIPTION OF THE LAKE CALA VERA PRESERVE TRAJL BOARDWALK
PROJECT ........................................................................................................................... 1
1.1 Applicant/Permittee ................................................................................................ 2
1.2 Responsible Parties (Financial Assurances) ........................................................... 2
1.3 Regional Resource Planning Context ..................................................................... 8
2.0 EXISTING CONDITIONS (BASELINE INFORMATION) ........................................ 9
2.1 Physical Conditions ................................................................................................ 9
2.2 Topography ............................................................................................................. 9
2.3 Soils .......................... : ............................................................ ; ............................... 10
2.4 Vegetation Communities ...................................................................................... 10
2.4.1 Disturbed Wetland ..................................................... : .............................. 10
'i 2.4.2 Coastal and Valley Freshwater Marsh ...................................................... 17
2.4.3 Southern Coast Live Oak Riparian Forest ................................................ 17
2.4.4 Southern Willow Scrub ............................................................................. 17
2.4.5 Cismontane Alkali Marsh ......................................................................... 18
2.4.6 Mulefat Scrub ............................................................................................. 18
2.4.7 Diegan Coastal Sage Scrub ....................................................................... 18
2.4.8 Disturbed Habitat ...................................................................................... 19
2.5 Sensitiv:e Biological Resources ............................................................................. 19
2.5 .1 Sensitive Plant Species ............................................................................. 19
2.5 .2 Sensitive Wildlife Species ........................................................................ 19
2.5.3 Wildlife Linkages and Corridors .............................................................. 20
2.5.4 Sensitive Vegetation Communities and Habitats ...................................... 20
2.5.4.3 Jurisdictional Waters ................................................................................. 21
2.6 Project Impacts ...................................................................................................... 21
2.6.1 Impacts to Upland Vegetation Communities and Land Covers ................ 22
2.6.2 Impacts to Jurisdictional Aquatic Resources ............................................ 22
2.6.3 Sensitive Species Direct Impacts .............................................................. 23
2.7 Biological Functions and Values of Areas to be Impacted ................................... 23
2.7.1 Functions and Services of Jurisdictional Aquatic Resources ................... 23
2.8 Required Mitigation for the Boardwalk Trail Project Impacts (Determination of
Credits) .............................................. : ...................... : ............................................ 25
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TABLE OF CONTENTS (CONTINUED)
Section Page No~
3.0 GOALS AND OBJECTIVES OF THE l\flTIGATION PROGRAM~ ....................... .27
3 .1 Biological Functions and Services to be Created and Enhanced .............................. 27
3.2 Objectives -Vegetation Communities to be Created and Enhanced ............... 28
3.3 Final Performance Standards ................................................................ : ............... 30
4.0 RESTORATION IMPLEMENTATION PLAN (WORK PLAN) ............................. .37
4.1 Rationale for Expecting Project Success (Site Selection) ..................................... 37
4.2 Existing Resource Impact Avoidance ................................................................ , ... 38
4.3 Site Access and Protection ........................................................................... : ........ 38
4.4 Erosion Control and Best Management Practices .............. , .................................. 41
4.5 Grading and Site Preparation ..................................................... :···_.······················ 41
4.6 Hydrology ............................................................................................................. 42
4.7 Irrigation System Installation.: ....... '. ............................................. ' ......................... 42
4.8 Recommended Plant Palettes ................................................................................ 43 •
4.9 Planting Materials ................................................................................................. 47
4.10 Time La,pse ............................................................ :··················· .. ·······················•·· 47
4.11 Preliminary Schedule ..................................................................................... _ ....... 48
4.12 Initial Establishment Period ........................................................... ; ...................... 48
4.13 As-Built Plan ..................................................................................... , ................... 49
4.14 Cost Estimate ........................................................................................................ 49
5.0 MAINTENANCE PLAN .................................................. : ...................... ; ....................... 51
I 5 .1 Maintenance Activities ......................................................................................... 51
5.1.1 Pest Management .............................. : ............... : ....................................... 51
5.1.2 Irrigation System and Hand Watering .... .' ................................................. 52
5.1.3 Trash Removal .......................................................................................... 53
6.0 MONITORIN'G REQlJIREMENTS .............................................................................. 55
6.1 Performance Standards ........................................... • .............................................. 55
6.1.1 Performance Standards ............................................................................. 55
6.1.2 Functional Wetlands Standards ................................................................. 56
6.1.3 Qualitative Monitoring .................................. _. ........................................... 58
6.1.4 Quantitative Monitoring ............................................................................ 58
7.0 REPORTING ..................................................................................................... : ............. 59
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TABLE OF CONTENTS (CONTINUED)
• Section Page-No.
8.0 CONTIN"GENCY ME.ASURES ............ H ........................................................................ 61
8.1 Adaptive Management .......................................................................................... 61
8, 1.1 Herbivory .................................................................................................. 62
. 8.12 Sediment Loss and Erosion Issues ............................................................ 62
8.1.3 Drought ... : ................................................................................................. 62
, .
9.0 COI\1PLETION OF MITIGATION .............................................................................. 63
9.1 Notification of Completion ................................................................................... 63
9 2 Agency Confirmation ............................................................................................ 63
10.0 ·SITE PROTECTION INSTRUMENT (LONG-TERM MANAGEMEN1) ................... 65
11.0. REFERENCES .......................................................................................... ; ...................... 67
APPENDICES
A Jv1ND Notice of Determination Mitigation Measures
B Preliminary Boardwalk Alignment (Plan and Photographs)
C Construction Plans for Lake Calvera Boardwalk Trail and Restoration
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TABLE OF CON.TENTS (CONTINUED)
Page No.·
LIST OF FIGURES
1 Regional Map ....................................................................................................................... 3
2 Vicinity Map ........................................................................................................................ 5
3A Existing Conditions with Proposed Boardwalk-West Portion ...... : .................................. 11
3B Existing Conditions with Proposed Boardwalk -East Portion .......................................... 13
3C Existing Conditions -Northeast Corner ......................... : ................................................... 13
4A Proposed Wetlands and Uplands Mitigation -West Portion ............................................ .31
4B Proposed Wetlands and Uplands Mitigation -East Portion ....................................... : ...... .31
4C Proposed Wetlands and Uplands Mitigation -Northeast Corner ....................................... 31
5 Wetland Creation Areas -Cross-Sections ......................................................................... 31.
LIST OF TABLES
1 Impacts to Upland Vegetation Communities and Land Covers (Acres) ............................ 22
2 Impacts to ACOE and CDFG Jurisdictional Wetland Vegetation Communities
and Land Covers and CDFG Jurisdictional Waters (Acres) (Revised 6/26/12
per ACOE impacts assessment) ......................................................................................... 23
3 Impacts to ACOE/CDFG Jurisdictional Aquatic Resource/ Uplands and
Required Mitigation (Revised 6/26/12 per ACOE impacts assessment) ......................... 25
4 Project Impacts and Proposed Mitigation (Revised 6/26/12 per ACOE
impacts assessment) .......................................................................................................... 29
5 Coastal Valley Freshwater Marsh Plant Palette· (0 .11 ac.) ................................................. 44
6 Southern Willow Scrub Plant Palette (0.20 ac.) ................................................................ 44
7 Southern Coast Live Oak Riparian Forest Plant Palette (020 ac.) ................................... .45
8 Southern Coast Live Oak Riparian Forest/Southern Willow Scrub Seed Mix
(0.40 ac.) ............................................................................................................................ 45
9 Diegan Coastal Sage Scrub Seed Mix (0.05 ac.) ....................... : ....................................... 46
10 Proposed Implementation Schedule ................................................................................... 48
11 Performance Guidelines for Created and Enhanced Wetlands
Vegetation Communities ................................................................................................... 56
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EXECUTIVE SUMMARY
The City of Carlsbad (City) proposes the construction of approximately 1000' of boardwalk as
part of improvements to the existing multi-use recreation trail system within the City owned 262-
acre Lake Calavera Preserve (Preserve). Improvements and maintenance to the existing multi-use
recreational trails and vie"'l)oints in the Lake Calavera Preserve are being implemented as part of
the Lake Calavera Trails Master Plan.
The proposed boardwalk system will replace informal trails developed within jurisdictional
wetlands upstream of Lake Calavera, including a crossing at a tn"butary to Agua Hedionda Creek
(Calavera Creek) and a secondary creek tributary. The boardwalk will elevate trail users above the
wetland and out of the creek preventing sedimentation of wetland waters; tramping vegetation and
compacting native soil. The boardwalk trail would be enhanced and widened in accordance with
the City's Habitat Management Plan for Natural Communities in the City. of Carlsbad (HMP,
Adopted 2004) and per the guidelines outline in this Final Wetland Habitat Mitigation and
Monitoring Plan (HMMP). The boardwalk will serve to protect functions of the wetland, while
providing services which benefit the public by allowing interaction within this fragile ecosystem.
Construction of the boardwalk would be funded through the City of Carlsbad Capital
Construction Improvements Program. The construction of the boardwalk would be broken up
into two phases. The first phase would cover the majority of the boardwalk running through the
main creek area. A second phase would be associated with a small tributary drainage in the
southeast portion of the project, which is currently' slated as an Eagle Scout project. These two
phases will be handled separately by the city for construction, but are being permitted together
with the resource agencies.
Impacts to jurisdictional aquatic resources for the boardwalk project includes impacts to 0.10-
acre of permanent and 0.06-acre of temporary impact to ACOE and CDFG jurisdictional
wetlands, totaling 0.16-acre of il;npacts. Additionally, 0.05 acre of CDFG only wetlands will be
permanently impacted and· 0.04-acre will be temporarily impacted. Impacts to upland
vegetation include 0.016 acre of permanent impacts and 0.003 acres of temporary impacts, for
a total of 0.019 acre to Diegan coastal sage scrub and disturbed habitat. Project impacts are
significant. per the City's HMP and require project mitigation measures be implemented to
reduce impacts to a level below significant.
Impacts to U.S. Army Corps of Engineers (ACOE), California Department of Fish· and Game
(CDFG)~ and Regional Water·Quality Control Board (RWQCB) jurisdictional wetlands, as well
as associated uplands will be mitigated through on-site creation, restoration and enhancement.
Vegetation communities that will be created ( established), restored and enhanced on site include
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southern willow scrub, freshwater marsh, southern coast live oak riparian forest and Diegan
coastal sage scrub. A total of 0.51 acres of combined jurisdictional wetlands will be created,
restored and/or enhanced, with an additional 0.05 acres ofDCSS will be created in order to serve
as a buffer to the created wetland mitigation areas in the north east portion of the project.
Mitigation will be .obligated to a 5-year maintenance and monitoring period until established
performance criteria is achieved and accepted by the resource agencies.
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1.0 DESCRIPTION .OF THE LAKE CALA VERA PRESERVE TRAIL
'BOARDWALK PROJECT
The City of Carlsbad (City) proposed boardwalk trail is part of improvements to the existing multi-
use recreation trail system within the City owned Lake Calavera Preserve (Preserve). The
approximate 262-acre Lake Calavera Preserve is located in the northeastern comer of the City of
Carlsbad, San Diego County, within unsectioned lands of the Agua Hedionda land grant on the
southeastern portion of the United Stat.es Geological Survey (USGS) 7.5' San Luis Rey, California
Quadrangle (Figures 'land 2).
The Lake Calavera Trails Master Plan (Master Plan) was approved by the City in January, 2QI0. The
Master Plan includes improvements and maintenance to approximately 6-miles ?f existing trails, to
accommodate hikers and non-motorized bicyclists. The proposed project would prevent this
uncontrolled loss of habitat through the implementation of an improved and managed trail system
designed to follow portions of the existing trail system.
The proposed elevated boardwalk trail will replace informal trails. developed within jurisdictional
wetlands upstream of Lake Calavera, including a crossing at a tnlmtary to Agua Hedionda Creek
(Calavera Creek) and a secondary creek tnlmtary. The boardwalk will elevate trail users above the
wetland and out of the creek preventing sedimentation of wetland waters, tramping vegetation and
compacting native soil. The boardwalk will serve to protect fimctions of the wetland, while providing
recreational benefit to the public by allowing a more manageable interaction within this fragile
ecosystem. Restoring degraded wetlands from informal egress and designating one trail will greatly
improve the biological fimctions of the creek and wetland areas.
The boardwalk trail would be designed and implemented in accordance with the City's Habitat
Management Plcmfor Natural Commwiities in the City of Carlsbad, Section F2 and F3 (HMP; Adopted
2004) and designated as a Type B trail. Type B boardwalk trails are intended for pedestrians and
bicyclists. The three segments of this trail type cross over site drainages, or are located within an area
that receives seasonal saturation; thus, 3 segments of boardwalk are proposed to be constructed to
enable safe year around crossing by trail users.
From shortest to longest, the length of boardwalk required at each segment range from approximately
25, 278, to 649 feet; the width and horizontal clearance of each boardwalk segment would be 6 feet
(with an overall construction zone of8 feet. This width includes an elevated edging along each edge
of the boardwalk for safety and to meet ADA requirements. It is anticipated that the construction of
all boardwalks would require an impact width 0(8 feet (construction zone); thus, the outer foot on
either side of the construction zone are considered temporary impacts (two feet total), which would
be revegetated as part of the mitigation program.
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Boardwalks are proposed to replace an existing highly trafficked informal trail system
established through sensitive wetlands, which includes user-constructed bridges made from
driftwood debris and salvaged construction materials. In addition, during months of high rainfall,
users. avoid saturateq areas by trampling on adjacent native vegetation. The construction: of
boardwalks would prevent trail widening and ensure that users stay within the designated trail.
Construction of tile boardwalk would be funded the City of· Carlsbad Capital Construction
Improvement Program and possibly grant funds that are currently in process for the project
However, the project is not dependent on the grant funds in_ order to move forward once permit
entitlements are obtained.
Impacts to U.S. Ariny Corps of Engineers (ACOE), California Department of Fish and Game
(CDFG), and Regional Water Quality Control Board (RWQCB) jurisdictional wetlands will be
mitigated for through on-site wetland creation, restoration and enhancement of jurisdictional
wetland vegetation communities. This document provides a conceptual · plan for the on-site
wetlands mitigation and associated uplands restoration and follows the general • compensatory
mitigation requirements as outlined by ACOE in the Federal Register (73 FR 19594-19705).
1 .. 1 · Applicant/Permittee
City of Carlsbad
Parks and Recreation Department
799 Pine Ave. Suite 200
Carlsbad, California 92008
Contact: Ms. Liz Ketabian
Phone. 7 60 .434.2978
Fax. 760.434.5088
1.2 Responsible Parties (Financial Assurances)
Dudek prepared this Final Wetlands Habitat Mitigation and Monitoring Plan (HMMP) in support
of the City's permit applications to ACOE, CDFG, and RWQCB. If the permits are granted by
the resource agencies, the City will be :financially responsible for the costs associated with the
implementation, monitoring, maintenance, and long-term protection of mitigation and restoration
areas as defined in this plan. The City will also be responsible for _all costs associated with
completion of the mitigation and restoration requirements herein. Further, The City will provide
access to the project areas for Restoration Ecologists, Habitat Restoration Contractor, and
permitting agency officials.
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The City will select a qualified Restoration Ecologist to monitor boardwalk installation,
mitigation and long-term maintenance of the mitigation and restoration areas. The Restoration
Ecologist and the City will review all aspects of the pertinent contract documents including, but
not limited to, boardwalk installation plans .and specifications, restoration plans and
specifications, site protection, contractor submittals, scheduling of formal site observations, lines
of communication, and persons with inspections, and stop work authority prior to project
implementation. The City, in consultation with the Restoration Ecologist will oversee and
coordinate implementation of boardwalk installation and this HMMP, including conducting or
overseeing field work for project installation and monitoring during the 5-year maintenance and
monitoring period. The Restoration Ecologist will possess specific knowledge and project-level
experience with wetlands establishment and enhancement projects, and at least 5 years of
wetlands restoration experience in California
The Restoration Ecologist also will be required to advise all project personnel of the on-site
construction restrictions resulting from the proposed implemenui.tion of boardwalk installation
and this HMMP, and the presence or potential presence of sensitive species and vegetation
communities within or adjacent to the project area, as well as known biological related dangers
on site (e.g., rattlesnakes, bee hives, poison oak, etc.). Information about federal, state, and local
laws relating to these biological resources will be discussed as part of the environmental
education program. Access and staging areas will be established outside of environmentally
sensitive areas. Project installation monitoring will occur throughout the boardwalk and
restoration _site construction period. Monitoring time may increase or decrease as required by
field conditions and construction activities.
The City will hire a contractor (Habitat Restoration Contractor) to conduct the restoration in
conjunction with boardwalk installation. If the City chooses to hire a separate contractor for
boardwalk construction/installation, the City and contractor shall coordinate the boardwalk
construction concurrent with restoration activities. The City will coordinate the installation
of the boardwalk in the small southeasterly tributary drainage, separately from the main
boardwalk construction.
The Habitat Restoration Contractor will be a qualified, licensed company, with experience in
native habitat restoration and maintenance. During the implementation phase, the Habitat
Restoration Contractor will be responsible for performing project installation, including site
preparation, grading, seeding, planting, erosion control, and other tasks as directed by the City,
Restoration Ecologist and as described in this HMMP. During the 5-year monitoring phase, the
Habitat Restoration Contractor will be responsible for irrigation, weed control, erosion control,
trash removal, replanting, and other tasks as directed by the City, R~oration Ecologist and as
descnoed in this HMMP.
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1.3 Regional Resource Planning Context
Projects located within the City's jurisdiction will be subject to the finalized, adopted version of the
HMP. The proposed project site is located within a proposed hard.line conservation area of the City's
HMP preserve system. With the final approval of the HMP in 2004, the Lake Calavera Project_site
receives the same conservation status as existing hardline areas and thus is designated as open space
(Adopted 2004, Section D, page D-14). Implementation of the project mitigation measures shall be
required to reduce impacts to a level -below significance and ensure consistency with the Multiple
Habitat Conservation Program (MHCP).
The Lake Calavera ttai1s Master Plan, including the segments of proposed boardwalk trails, have
undergone CEQA review and a Mitigated Neg. Dec was filed on January 27, 2010 for HMP 09-05
for Doc. # 100020. The State Cleaning house number is 200907109. A copy of the Notice of
Determination for the MND and the Mitigation Measures for the Lake Calavera Trails Master Plan
are attached as Appendix A and referenced herein.
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2.0 EXISTING CONDITIONS (BASELINE INFORMATION)
Biological surveys of the project site were conducted by Merkel & Associates, Inc. (M&A)
between 2005 to 2009 to identify the biological resources present and analyze biological impacts
throughout the Lake Calavera Trails Study Area. Survey <.:Iata relevant to the Boardwalk project
are included below,-as presented in the Lake Calavera Trails Biological Resources Report
(Merkel and Associates, 2009). M&A mapped the vegetation on site, performed a jurisdictional
wetland delineation, and conducted protocol surveys for the federally listed, endangered vernal
pool branchiopods [i.e., San Diego fairy shrimp (Branchinecta sandiegonensis)], federally and
state listed, endangered least Bell's vireo (Vireo bellii pusillus), federally listed, endangered
southwestern willow flycatcher (Empidonax traillii extimus), and federally listed, threatened
coastal California gnatcatcher (Polioptila califomica califomica). In addition, M&A biologists
surveyed for the federally listed, threatened thread-leaved brodiaea (Brodiaeafilifolia).
Dudek Habitat Restoration Specialists John Minchin and Stuart Fraser conducted field
surveys within the study area specific to construction of the proposed boardwalk and to . .
evaluate mitigation opportunities (2011). The survey efforts were focused on vegetation,
jurisdictional waters, and sensitive plant and animal species. General biological surveys and
focused botanical and wildlife studies were also conducted within the study area by M&A.
Descriptions included below summarize the results of those surveys. A preliminary plan view
layout of the boardwalk. with representative photographs taken along the boardwalk
alignment are shown on Figure B-1 (Appendix B).
2.1 Physical Conditions
The Boardwalk project area is situated along a USGS unnamed tributary (Calavera Creek) to
Agua Hedionda Creek, which occurs approximately one mile southwest of the site. Coordinates
iocate the project site at 33deg.10'23N and 117deg.16'52" W. The project area is situated
northeast and upstream of a man-made earth-fill dam and reservoir (called Lake Calavera) that
currently impounds runoff from the upper Calavera Creek watershed. The Boardwalk project
area is located in the northeastern portion of the Lake Calavera Preserve with single-family
res1dences located on the north, east and west and an adjacent CDFG preserve to the south.
2.2 Topography
The Boardwalk project area is located within a broad drainage area subject to seasonal flooding
and ponding. Elevations within the Boardwalk project area range from approximately 215 feet
above mean sea level (AMSL) at the main creek crossing, between 224 and 228 AS:ML at the
upstream tributary crossing and at between 228 and 244 feet ASML in the upstream stretch.
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Construction of the dam and creation of the reservoir/impoundment downstream has
effected/impacted: site physiography. Slopes draining into drainage surrounding the project site
are gentle with steep slopes on the flanks of Mount Calavera to the south.
2.3 Soils
According to Bowman (1973), Salinas clay loams covers 100% of the study area. The Salinas
series consists of well drained and moderately well drained clay loams that washed from the
Huerhuero complex and Las Flores loamy fine sand. These soils are found in flood plains and
alluvial fans and have slopes of 0-9%. In a representative profile, the Sl.}l'face layer is dark
grayish brown clay loam and neutral to mildly alkaline to about 22 inches. The subsoil is dark
grayish-brown heavy clay loam and clay and mildly alkaline (pH 7.4) to a depth of more _than 60
inches. The erosion hazard is slight to moderate.
2.4 Vegetation Communities
An analysis of vegetation communities is provided in the Lake Calavera Trails Biology Resources
Report (Merkel and Associates 2009). According to this report, and follow-up reconnaissance by
Dudek (2011), the project area supports predominantly wetlands habitat with patches of disturbed
coastal sage and disturbed habitat (trails). A total of 8 vegetation c9mmunities and land covers
were .identified within the boardwalk and restoration project area, including disturbed wetland,
coastal and valley freshwater marsh, southern coast live oak riparian forest, southern willow scrub,
mulefat scrub, cismontane alkali marsh, Diegan coastal sage scrub, and disturbed habitat. (Figures
3A, 3B and 3C). Characteristics of the vegetation communities present on site are described below.
2.4.1 Disturbed Wetland
Disturbed Wetland (DW) has been mapped within the proposed boardwalk construction portion
of the study area adjacent to southern willow scrub and freshwater marsh. This vegetation
community is comprised of open and patchy flora species including non-native and native
species. This area is heavily dominated by pampas grass (Cortaderiajubata) with several coyote
brush (Baccharis pilularis) shrubs and non-native annual forb species intermixed. In-some cases,
heavily compacted and unvegetated areas within ACOFJCDFG or CDFG jurisdictional areas
were mapped as disturbed wetland. Toe majority of trails and pathways located within a •
designated V€::getation community were classified as a 'disturbed' variant (i.e., disturbed
Southern Willow Scrub).
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2.4.2 Coastal and Valley Freshwater Marsh
Coastal and Valley Freshwater Marsh (FWM) habitat occurs along within the wetland
depressions periodically _flooded during high water conditions. The portion of this vegetation
community present on the project site is dominated by low herbaceous species including Yerba
mansa (Anemopsis californica) and low emergent monocots including Mexican rush (Juncus
mexicanus), Spiny rush (Juncus acutu.s), pale spike-sedge (Eleocharis macrostachya), broad-
leaved cattail (Typha latifolia) and California bulrush (Scirpus californicus). Other herbaceous
species including broad-leaved cattail (Typha latifolia), California bulrush (Scirpus californicus)
and salt marsh fleabane (Pluchea odorata) occur in patches.
Disturbed Freshwater Marsh ( dFWM) is present on trails and pathways located within
Freshwater Marsh. Site disturbance, including repeated mechanical perturbation has altered the
vegetation composition such that the shrub cover percentage is below I 0% and there is a high
prevalence of compacted soils and impacted vegetation along the trail fringe. All dFWM
vegetation is located within ACOE/CDFG jurisdictional wetlands.
2A.3 Southern Coast Live Oak Riparian Forest
Individual trees, as well as small groves of coast live oak (Quercus agrifolia ), occm. within the
Southern Live Oak Riparian Forest (SLORF) habitat areas, which occur along the tributary
drainages, and the mesic areas upstream from the reservoir. Most of the oaks are mature trees
with a height and similar canopy width ranging from 20--40 feet. The understory includes mostly
leaf-litter, which serves to keep the soil and roots of these trees cool and moist during the dry
summer months. Along the canopy fringe, several shade-adapted species were detected. Included
here were California peony (Paeonia californica), checker-bloom (Sidalcea malvaejlora ssp.
sparslfolia) and coast jepsonia (Jepsonia parryi).
Disturbed Southern Live Oak Riparian Forest (dSLORF) is present on trails and pathways
located within Southern Live Oak Riparian Forest. Site disturbance, including repeated
mechanical perturbation has altered the vegetation composition such that the shrub _cover
percentage is below 10% and there is a high prevalence of compacted soils and impacted
vegetation along· the trail fringe. dSLORF vegetation communities are located within either
ACOFJCDFG or CDFG jurisdictional wetlands.
2.4.4 Southern WIiiow Scrub
Southern Willow Scrub (SWS) habitat is the predominant vegetation community located along
Lake Calavera Creek, upstream from the reservoir:. Much of this habitat includes willow species
ranging from 20 to 40 feet in height. Included here are arroyo willow (Salix lasiolepis), lance-
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leaf willow (Salix lucida ssp. lasiandra) and Goodding's black willow (Salix gooddingii).
Several small groves of California fan palm (Washingtonia filifera) have invaded the upstream
portion of the site. In the most mesic locations, freshwater marsh habitat including dense stands
of California bulrush and broad-leaved cattail comprise the understory. In drier areas, the
understory includes a high diversity of shrub and herbaceous plant species. The • shrub layer
includes mulefat, narrow-leaved willow (Salix exigua), and western poison oak (Toxicodendron
diversilobum). The herbaceous. layer includes yerba mansa, San Diego sedge (Carex spissa), and
variety of rushes including Mexican rush, mariposa rush (Juncus duhius), and the sensitive flora
species spiny rush.
Disturbed Southern Willow Scrub ( dSWS) is present on trails and pathways located within
Southern Willow Scrub. Site disturbance, including repeated mechanical perturbation has altered
the vegetation composition such that the shrub cover percentage is below 10% and there is a high
prevalence of compacted . soils and impacted vegetation along the trail fringe. All dSWS
vegetation communities are located within ACOE/CDFG jurisdictional wetlands.
2.4.5 Clsmontane Alkali Marsh
Patches of Cismontane Alkali Marsh (CAM) are found in mesic locations upstream of the
reservoir. High evaporation and low input of freshwater render these areas somewhat salty. The
dominant species of this habitat is yerba mansa (Anemopsis califomica) and saltgrass (Distichlis
spicata). Other species present include western ragweed (Ambrosia psilostachya), Mexican rush
(Juncus mexicanus), and spiny rush (Juncus acutus ssp. leopoldii). Non-native plants such as
celery (Apium graveolens), annual beard grass (Polypogon monspeliensis), and Gurly dock
(Rwnex crispus) are also present.
2.4.6 Mulefat Scrub
Mulefat Scrub (MFS) occurs in patches upstream of the reservoir and is typically situated
between freshwater marsh and upland habitat types such as Diegan coastal sage scrub. It is
typically characterized as a monotypic shrub community with mulefat (Baccharis salicifolia) as
the predominant species. Occasional young willows may also be found in this habitat, though in
most cases individual willows are mapped as southern willow scrub. Understory plants include
wetland associates such as saltgrass and in shady areas cocklebur (Xanthium strumariwn).
2.4. 7 Diegan Coastal Sage Scrub
Diegan Coastal Sage Scrub (DCSS) habitat on site includes several monotypic stands of coyote
brush located moist areas adjacent to/southern willow scrub vegetation communities have been
mapped as DCSS by M&A. These areas are dominated by coyote brush with very little
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understory; however, in more mesic portions of the study area bristly ox':'tongue (Picris
echioides) and western poison oak can be found.
2.4.8 Disturbed Habitat
.Areas mapped as Disturbed Habitat (DH) on site follow the 11:HCP definitions for disturbed
habitat. Per this definition, vegetative cover comprises less than 10% of the surface area and
there is evidence of soil surface disturbance and compaction (i.e., grading). Some areas may
exceed 10% vegetative cover; however, there is soil disturbance and the presence of debris.
Disturbed habitat is mapped for the numerous walking/bike trails located outside of ACOE and
CDFG jurisdiction wetland areas and for the non-native annual weed dominated slopes located in
the northeast comer of the Preserve site.
2.5 Sensitive Biological Resources
Sensitive biological resources are those defined as follows: (1) species that have been given
special recognition by federal, state, or local conservation agencies and organizations due to
limited, declining, or threatened population sizes; (2) species and habitat types recognized by •
local and regional resource agencies as sensitive; (3) habitat areas or vegetation communities that
are unique, are of relatively limited distribution, or are of particular value to wildlife; and (4)
wildlife corridors _ and habitat linkages. Regulated biological resources may or may not be
considered sensitive, but are regulated under local, state, and/or federal laws.
2.5.1 Sensitive Plant Species
An analysis of sensitive flora for the Lake Calavera Preserve is provided ii:J. the Lake Calavera
Trails Biology Resources Report (Merkel and Associates 2009). According to this report, Spiny
rush (Juncus acutus spp . .leopoldii) (CNPS List 42)(CNPS, 2001) was identified within the
wetland vegetation communities proposed for the boardwalk trail project
2.5.2 Sensitive Wildlife Species
Surveys for sensitive wildlife were conducted by Merkel and· with information provided in the
Lake Calavera Trails Biology Resources Report (Merkel and Associates ·2009). According to this
report, 13 sensitive fauna species were detected within the Lake Calaveras Preserve Site, they
include the western spadefoot (.Scaphiopus hammondii), monarch (Danaus plexippus) , white-
tailed kite (ElamJS leucurus), northern harrier (Circus cyaneus), sharp-shinned hawk (Accipiter
striatus), Cooper's hawk (Accipiter cooperil), Nuttall's woodpecker (Picoides nuttalliz),
loggerhead shrike (Lanius ludoviciamLS), coastal California gnatcatcher (Polioptila califomica
californica), California thrasher (Toxostoma redivivwn), yellow warbler (Dendroica petechia
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brewsterz), yellow-breasted chat (Icteria virem), and tricolored blackbird (Agelaius tricolor).
Although no nests were observed during the surveys, it is possible for the raptor species to nest
on-site within southern coast live oak riparian forest or southern willow scrub.
No least Bell's vireos and no southwestern willow flycatchers were detected on the project site
during the focused surveys. Brown-headed cowbirds (Molothrus ater) were detected within the
northeastern portion of the Preserve. Tricolored blackbirds were also detected within the
northeaster.ti portion of the study area.
2.5.3 Wildlife Linkages and Corridors
An analysis of habitat linkages and corridors for the Lake Calavera .Preserve is provided in the
Lake Calavera Trails Biology Resources_ Report (Merkel and Associates 2009). According to this
report, the Lake Calavera Preserve has been identified in the within the Local Facilities
Management Zone (LFMZ) 14 (City Adopted 2004). This zone includes Core 3 (approximately
1,163 acres), which contains large areas of coastal sage scrub that support critical populations of
the threatened coastal California gnatcatcher and thread-leaved brodiaea. Other sensitive habitats
• within Core 3 include chaparral, grasslands, and wetland communities. Core 3 has direct linkages
to other Core areas including Core 2, Core 4, and Core 5. Downstream of the reservoir, Linkage
Area B connects Core 3 to Core 4 (i.e., Agua Hedionda Lagoon and environs).
The Lake Calavera Preserve retains some connectivity between Agua Hedionda Lagoon and
Robertson Ranch. El Camino Real, a heavily trafficked highway, separates the back lagoon
riparian habitat from Robertson Ranch. In addition, ~e expansion of College Boulevard has
slightly interrupted this corridor. Moreover, habitat north of the El Camino Real now consists of
a palm nursery and the agricultural lands of Robertson Ranch. 1bis connection northward is,
therefore, tenuous at present, but does not preclude future enhancement, insofar as urban
hardscape ( other than the road) is not in place. The Lake Calavera Trails study area functions as
a wildlife corridor supporting movement of individuals (and thus genetic material) from within
Core 3 to adjacent Core areas westward and vice versa
2.5.4 Sensitive Vegetation Communities and Habitats
An analysis of Sensitive Vegetation and on site is provided in the Lake Calavera Trails
Biology Resources Report (Merkel and Associates 2009). A summary of this information is
provided below.
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2.5.4. 1 Wetlands
Wetland habitat types have extremely high wildlife values, are naturally limited in distribution,
and also have· been substantially depleted within southern California. Numerous species,
including several sensitive species, are dependent on these habitats for food, cover, and breeding,
and several additional species, although not dependent on these habitats, utilize these areas on a
regular basis: The on-site wetlands are considered sensitive due to their high quality habitat,
which support many common and sensitive riparian wildlife. •
2.5.4.3 Jurisdictional Waters·
Details of the jurisdictional wetland delineation performed by M&A, including survey dates
and times is provided in the Lake Calavera Trails Biology Resources Report (M&A, 2009).
According to this report, the jurisdictional wetland delineation was performed using the routine
on-site determination methods noted in the 1987 Army Corps of Engineers' (ACOE) Wetland
Delineation Manual (Environmental Laboratory 1987). In addition, the delineation effort was
expanded to identify wetlands/non-wetland waters of the U.S. and streambeds under federal
and state jurisdiction, respectively. Evidence supporting jurisdictional determinations was
recorded on wetland field data forms and depicted in photographs of the data points. Wetland
habitats and jurisdictional waterways were plotted on an aerial map (with topographical
overlay) of the study area.
2.6 Project Impacts
The construction footprint of the proposed boardwalk, including the temporary impacts
associated with installation, was carefully evaluated by M&A (2009) and Dudek (2011) to
minimize impacts to biological resources within the Lake Calavera Preserve. The proposed
boardwalk footprint was carefully aligned with the existing informal trail present on site. The
selected alignment was chosen to minimize impacts to jurisdictional aquatic resources by
avoiding existing mature willow, ponding and standing water (as practicable) and mature spiny
rush (CNPS List 4.2) plants. Installation of an elevated boardwalk as a trail improvement will
promote the natural flow patterns of seasonal wetland flooding below the boardwalk and
eliminate impacts to the current wetland substrate; including trampling of herbaceous vegetation,
compacting of surface soils and generating sediment from foot and bicycle traffic. The proposed
trail alignment also minimizes impacts to sensitive upland vegetation communities by utilizing
the existing pathway (disturbed habitat) to the greatest degree possible. Although impacts to
sensitive resources were minimized by access route selection and modifications, some impacts to
jurisdictional aquatic resources were unavoidable and are described in detail below and depicted
in Table 1 and Figures 3A, 3B and 3C.
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Table 2
Impacts to ACOE and CDFG Jurisdictional Wetland Vegetation Communities and Land
• Covers and CDFG Jurisdictional Waters (Acres)
(Revised 6/26/12 per ACOE impacts assessment)
Vegetation Community Map Code Permanent
Southern Willow Scrub (ACOE/CDFG) sws 0.06
Freshwater marsh (ACOE/CDFG) FWM 0.03
Southern Coast Live Oak Riparian Forest (ACOE/CDFG) SCLORF 0.001
Total 0.10
Drainaqe (CDFG only) <0.001
Southern Coast Live Oak Riparian Forest (CDFG onlv) SCLORF 0.049
Total 0.05
2.6.3 Sensitive Species Direct Impacts
Temporary Total
0.02 0.08
0.03 0.06
0.001 0.002
0.06 0.16
<0.001 <0.001
0.039 0.088
0.04 0.09
Approximately IO spiny rush plants would be directly impacted from the Lake Calavera Trails
project. Spiny rush populations in San Diego County are now relatively stable despite several
decades of losses associated with widespread regional reductions in wetlands. The direct impacts
to spiny rush, a California Special Plant, are not considered significant as the loss of these plants
is not expected to _threaten to eliminate a plant community and thus would not require project
mitigation measures. However, the City has agreed to include container plants of spiny rush
within the wetland mitigation planting plan (M&A, 2009).
2.7 Biological Functions and Values of Areas to be Impacted
2. 7.1 Functions and Services of Jurisdictional Aquatic Resources
Jurisdictional wetland communities that will be impacted by the project are within the Lake
Calavera Preserve. Therefore, their functions and services are consistent with the functions and
services of the habitat within the overall preserve, which are generally to provide habitat to plant
and wildlife species.
The functions and services of jurisdictional wetland communities on site generally include the
functions and services typical of natural vegetated wetland and riparian communities, such as
dissipation of energy, cycling of nutrients, uptake of elements and compounds, retention of
particulates, export of organic carbon, and maintenance of plant and animal communities ( e.g.,
nesting, feeding, and breeding opportunities for various aquatic, terrestrial, and avian animals).
hnpacts to southern willow scrub will occur to the outer fringe of the willow canopy along the
riparian corridor, and will include primarily impacts to the understory vegetation.
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The riparian vegetation and marsh, habitats contribute to the site's high biological functions and
services. The riparian vegetation, particularly the southern willow scrub, consists of moderately
dense vegetation that provides a multi-:layer canopy, which supports many common riparian_
birds, such as yellow-rumped warbler (Dendroica coronata), song sparrow (Melospiza melodia),
lesser goldfinch_ (Carduelis psaltria)? common yellowthroat (Geothlypis trichas). The on-site
wetlands do support several sensitive riparian birds such as the yellow warbler, yellow-breasted
chat, ~d various raptors. Additionally, :the smaller ponding areas and abundance of leaf litter
beneath the larger stands of willows are expected to provide breeding habitat for various
common amphibian species including the Pacific chorus frog (Pseudacris regilla) and western
toad (Bufo boreas). The marsh and open water habitats also contribute to the site's high wildlife
diversity and abundance by supporting numerous wildlife species (M&A, 2009).
The disturbed southern willow scrub, disturbed freshwater marsh and disturbed wetland include
the informal trails and pathways established over time from recreational user groups .located in
jurisdictional wetlands. These areas provide very limited functions to plants and wildlife. The
functions that they may provide for wildlife are for dispersal routes and migration corridors. Soil
impacts include compaction and increased erosion due to recreational traffic. Soil compaction
reduces available water holding capacity, infiltration and soil permeability, which increases
runoff. It can also impede root growth and soil biological activity. Erosion can cause the loss of
topsoil and downstream sedimentation.
Open water exists in the perennial creek, and seasonal ponds and depressions. It provides wildlife
function to aquatic species and waterfowl for foraging and nesting. The.open water also provides a
drinking source for wildlife. Hydrologic functions include long-term surface water storage,
subsurface water storage, retention of sediment and organic particulates and moderation of
groundwater flow or discharge.
The impacts that will occur to the area mapped as freshwater marsh, and include open water. These
areas will be marginally affected. The proposed boardwalk will be elevated above existing open
water and allow for the natural movement of flowing water through the project area. Ponded and
flowing open water will remain and continue to provide functions and for aquatic species and
waterfowl. Thus, the functions of the open water will not be lost.
Enhancement of the trail system through construction of the boardwalk will allow human user
groups to enjoy the benefits of the existing ecosystem without the dangers and hazards of the
current unimproved conditions of the trail system. Enhancing the trail will also provide increased
access opportunities for trail users to learn more about wetlands and their value through the
installation of interpretive panel educating trail users along the route.
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2.8 Required Mitigation for the Boardwalk Trail Project Impacts
(Determination of Credits)
The applied mitigation ratios for impacts to vegetation types including permanent and temporary
impacts resulting from the construction of the boardwalk, which is part of the proposed trail
system, are consistent with Table 11 of the City's HMP (Adopted 2004) and are shown in Table
3. Mitigation for wetland habitats have been provided, per the requirements of the HMP, but are
subject to review under section 404 of the federal Clean Water Act and Section 1600 of the
California Fish and Game Code. The HMP allows for impacts to DCSS and disturbed habitat to
mitigate out-of-kind within the Calavera Preserve, in order to promote building the preserve
system into a larger, contiguous area.
As required of the City's HMP (Adopted 2004), analysis of proposed impacts to wetlands
consisted of a three-step process. The first step involved determining whether the impacts are
avoidable or unavoidable. Secondly, for unavoidable impacts, the allowable amount of
encroachment was determined. The final step involved determining the mitigation for
unavoidable impacts.
Vegetation
Community
Southern Willow Scrub
(ACOE wetland/
CDFG)
Freshwater marsh
(ACOE wetland/
CDFG)
Southern Coast Live
Oak Riparian Forest
(ACOE wetland/
CDFG)
Open Water (ACOE
non-wetland/CDFG)
Table 3
Impacts to ACOE/CDFG Jurisdictional Aquatic Resource/
Uplands and Required Mitigation
(Revised 6/26/12 per ACOE impacts assessment)
Impacts Mitigation Ratio Required Mitigation
p T p T (For Permanent Impacts) 1
ACOE Wetlands I CDFG Wetlands
0.06 0.02 3:1 1:1 0.18
0.03 0.03 2:1 1 :1 0.06
0.001 0.001 3:1 1:1 0.003
0.008 0.008 2:1 1:1 0.0164
(12 LF)
Subtotal 0.10 0.06 0.26
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Mitigation for
Temporary Impacts
(restoration In place)
0.02
0.03
0.001
0.0084
0.06
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Vegetation
Community
Drainage (CDFG only)
Southern Coast Live
Oak Riparian Forest
(CDFG only)
Table 3
Impacts to ACOE/CDFG Jurisdictional Aquatic Resource/
Uplands and Required Mitigation
(Revised 6/26/12 per ACOE impacts assessment)
Impacts Mitigation Ratio Required Mitigation
p T p T (For Permanent Impacts) 1
CDFG Wetlands Only
<0.001 <0.001 1.5:1 ---<0.00152
0.049 0.039 3:1 1 :1 0.147
Subtotal 0.05 0.04 0.148
Total Wetlands 0.15 0.10 0.408
(Acoe/CDFG & CDFG
Only)
Uplands
Disturbed Habitat 0.016 0.003 1:1 ---<0.0013
1 Mitigation for Permanent impacts requires a minimum of 1:1 wetland creation
2 Permanent impacts to Non-wetland WOUS will be mitigated through wetland creation
3 Permanent and temporary impacts to Disturbed Habitat will be mitigated though DCSS restoration
4 Mitigation for impacts to open water will be provided through freshwater marsh creation and enhancement
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Mitigation for
Temporary Impacts
(restoration In place)
---
0.039
0.039
0.099
0.0033
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3.0 GOALS AND OBJECTIVES OF THE IVUTlGA TION PROGRAM
The goals of the mitigation program are to:
• Satisfy the mitigation requirements of local, state, and federal agencies for impacts to
jurisdictional aquatic resources through the creation of ACOE and CDFG jurisdictional
wetlands and the restoration ( enhancement) of functions and services in currently
degraded wetland systems.
• Restore habitat functions to disturbed or degraded upland vegetation communities and
increase the functions and values of existing land covers through conversion to viable
native upland habitat resilient to exotic invasion.
• To provide an adequate upland buffer (30') for created wetlands at the interface with
urban or disturbed areas.
• Remove all non-native, exotic/invasive weed species considered to be highly invasive on
the Cal-IPC '-'Invasive Plant Inventory'' lists A and B (2006).
• Prevent any impacts to sensitive wildlife species during implementation of the project
construction and long-term maintenance activities.
• • • Utilize erosion control measures in the form of ''Best Management Practices" (BMPs) on
the site as conditions necessitate.
Project objectives are included in Sections 3.1 -3.3
3.1 Biological Functions and Services to be Created and ~nhanced
The restoration plan focuses on increasing the functions and services of the project she through
the increasing the functional wetland area through creation of additional wetlands and increasing
the functional value of existing degraded jurisdictional wetland area through enhancement:
Wetland creation will include ·expanding the riparian corridor and active :floodplain footprint of
the existing tributary (Calavera Creek). Initial assessment indicates that the proposed plan will
increase wetland functions in the floodplain in locations where it currently does not exist. _The
proposed creation area is currently elevated approximately 3-4 feet above the active floodplain
with no wetland hydrology (non-jurisdictional ACOFJCDFG wetland) currently present. Based
on the proposed design, the excavation/grading of the area and the addition of surface hydraulic
inlet/outlet connections from .the adjacent wetland (FWM) to the creation area will facilitate a
localized increase of floodwater storage. Hydrologic functions, including long-term surface
water storage and energy dissipation, are projected to improve from the introduction of seasonal
inundation and increased proximity to the -groundwater table, as well as the addition of native
wetland and transitional wetland vegetation. Dynamic surface water storage· and sub-surface
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water storage are projected to have a slight increase due to the expanded floodplain area that will
receive prolonged saturation and be available for water percolation.
For both the wetland creation and ·enhancement areas, biogeochemical functions including
nutrient cycling, removal of imported elements/compounds, and retention of sediment and
organic particulates are all projected to improve due to an increased density of woody plant
materials, improved on-site micro-topographic complexity, and· accelerated primary productivity
resulting from installation trees, shrubs, and he_rbaceous vegetation, as well as expansion of the .
freshwater marsh vegetation component. The mitigation sites will provide additional potential for
bio-filtration of nutrients and associated constituents on site.
Vegetative functions including maintenance of community type and detrital biomass, both of
which are currently absent wetland functions in the _creation areas and severely degraded in the
restoration areas, will be created as species composition increases, as trees and shrubs dominate
more of the total vegetative cover and as natural regeneration of woody plants improves ( over
time, with seed from plantings and upstream propagules). An establishment of an upland DCSS
buffer adjacent to the wetland creation area will protect the wetland creation area from the
invasion of non-native weed seed and viable propagules. Maintenance of distribution and
abundance of invertebrates and vertebrates are both projected to increase; additional habitat will
be created on site for aquatic invertebrates, .and additional plant species and resulting leaf-litter
biomass will provide enhanced habitats for terrestrial invertebrates. It is also projected 1?,at the
trophic interactions of vertebrate guilds and species now absent on site will increase with the
additional inputs of biomass, seasonal variation of plant materials, improved vertical
stratification of vegetation on site, and increased habitat for invertebrates.
3.2 Objectives -Vegetation Communities to be Created
and Enhanced
Vegetation communities that will be created and enhanced on site include southern willow
scrub, freshwater marsh, southern coast live oak riparian forest and Diegan coastal sage scrub.
A total of 0.51 acres of combined ACOFJCDFG and CDFG-only jurisdictional wetland will be
created or enhm;tced with an additional 0.05 acres of DCSS created to serve as an additional
buffer to the created wetland mitigation area in the northeastern portion of the site (Table 4 and
Figures 4A, 4B and 4C).
Restoration will be implemented to increase the functions and values (i.e., services) of existing
degraded ACOE/CDFG and CDFG wetland vegetation communities including FWM, SWS,
SCLORF, DCSS and DW. Degraded wetland vegetation communities currently include areas
currently degraded from unregulated trail use through the existing wetland and areas dominated
by non-native annual weeds and perennial exotic vegetation. Additionally, areas temporarily
impacted during boardwalk construction will also be restored in place.
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Vegetation
Community
Southern Willow
Scrub
(ACOE/CDFG)
Freshwater marsh
(ACOE/CDFG)
Southern Coast
Live Oak Riparian
Forest
(ACOE/CD~G)
Open Water (ACOE
non-Wetland/
CDFG)
Subtotal
Drainage (CDFG
only)
Southern Coast
Live Oak Riparian
Forest (CDFG only)
Subtotal
Grand Total
Wetlands
(ACOE/CDFG and
CDFG Only)
Disturbed Habitat
Table 4
Project Impacts and Proposed Mitigation
(Revised 6/26/12 per ACOE impacts assessment)
Mitigation Proposed Mitigation
Impacts Ratio (For Permanent Impacts)
p T p T Creation1 Restoration/ Total
Enhancement1
ACOE WeUands/CDFG Wetlands
0.06 0.02 3:1 1 :1 0.11 ac. 0.069 ac. 0.18 ac.
(N.E. Corner) (Trail/Enhan)
0.03 0.03 2:1 1:1 0.06ac. 0.012 ac. 0.07 ac.
(N.E. Corner) (Trail/Enhan)
0.001 0.001 3:1 1:1 0.12 ac. 0.040 ac. 0.16 ac.
(N.E. Corner) (Trail/Enhan)
0.008 0.008 2:1 1 :1 PartofFWM Part of FWM Part of
above. above. FWM
above.
0. 10 0.06 --0.29 0.72 0.47
COFG Wetlands Only
<0.001 <0.00 1.5:1 1:1 PartofSWS Part of SWS Part of
1 above. above. sws
above.
0.049 0.039 3:1 1 :1 Part of Part of Part of
SCLORF SCLORF SCLORF
above. above. above.
0.05 0.04 - -See above See above See
above
0.15 0.10 --0.29 0.12 0.41
Uplands
0.016 0.003 1 :1 -0.05 restoration 3
1 Mitigation for Permanent impacts requires a minimum of 1 :1 wetland creation and 2:1 wetland enhancement
2 Permanent impacts to CDFG Wetlands only will be mitigated through wetland creation and enhancement
Mitigation Mitigation
for Total
Temporary (Penn.
Impacts and
(resfotation Temp.)
in place)
0.02 0.20
0.03 0.10
0.001 0.161
0.008 0.008
0.06 0.47
<0.001 0.001
0.039 0.039
0.04 0.04
0.10 0.51
0.003 0.05
3 Permanent and temporary impacts to Disturbed Habitat will be mitigated for though DCSS restoration in north/east corner at higher ratio
Wetland creation will consist of grading and planting areas of currently existing non-
jurisdictional upland disturbed habitat to wetland habitat. These areas include an area adjacent to
the proposed eastern boardwalk terminus and the lower slope in the northeast corner of the
Preserve. Both creation areas are directly adjacent to ACOE/CDFG jurisdictional FWM
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vegetation communities and are expected to receive seasonal floodwater inundation. Vegetation
communities proposed for these areas include FWM, SWS and SCLORF. An approximate 20-
foot wide upland buffer zone will be included adjacent to the northeastern wetland-creation-areas
to serve to.protect the integrity of the restoration efforts, including improved wildlife values and
to help eliminate the invasion of weeds and perennial exotics in this area. This buffer will also
serve to help mitigate for los~es to upland habitat on site.
The evaluation of the success of creating, restoring and enhancing viable native wetland and
upland habitat, as described in this CWMMP, will be based on achievement of specific
performance criteria, derived from established reference data collected from viable existing
reference vegetation communities within the Preserve.
3.3 Final Performance Standards
The final ·success criteria outlined herein will be used to determine completion of the City's
mitigation responsibilities. Success'criteria has been developed based on the requirements of the
Guidelines for Habitat Creation and Restoration (City of Carlsbad, 2009) including comparison
to local reference sites that match the s.elected restoration site in terms of soil, slope, aspect and
vegetation community. Fulfillment of these criteria will demonstrate that the mitigation site has
become established and self-sustaining, and that the desired habitat functions and values (i.e.,
services) are being achieved which will-fulfill the long-term goals of the mitigation effort. See
Section 6; 1 for specific performance standards addressing vegetative cover goals that are
intended to guide the restoration efforts, such that final project success is achieved.
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4.0 Rl;:STORATION IMPLEMENTATION PLAN (WORK PLAN)
The restoration/revegetation program shall be implemented per the final construction documents,
' ' (i.e., Construction Plans for Lake Calavera Boardwalk Trail and Restoration, Dudek June 2012)
included for reference in Appendix C.
The Implementation Plan includes the following:
• Vegetation removal and grubbing prior to grading and construction,
• Exotic/invasive .species removals from proposed mitigation/revegetation areas,
• Grading to elevations compatible with the flow gradient of Calavera Creek,
• Applying mulch or other amendments (as necessary to address soil deficiencies) and
in~rporating into topsoil,
• -Installing temporary irrigation system (for wetland creation area and buffer zone area only), _
• Weed control through weed reduction (i.e., grow-and-kill) cycles,
• Installing native container plants,
• Applying native seed mix,
• hnplementing a 5-year maintenance and monitoriug period.
4.1 Rationale for Expecting Project Success (Site Selection)
The wetlands creation areas will be graded to receive overbank flow and flood inundation from
Calavera Creek. Creation area grading will be set to the adjacent ACOFJCDFG jurisdictional
gradient to allow for normal flood inundation through the reach of Calavera Creek (Figure 5).
Wetland creation, restoration and enhancement is proposed for the vegetation communities that
existed prior to temporary impacts or exist directly adjacent to viable native habitat. Thus, it is
assumed that the appropriate conditions will be present for .re-establishing the same habitats.
Creation, restoration and enhancement areas will be planted with species found in adjacent
vegetation communities observed successfully growing on site. With the use of plant species
adapted to the site conditions, probability of project success is increased.
The natural tendency of native wetland vegetation to recruit into open areas with sufficient soil
moisture, combined with container plant installation and a native seed mix application, is expected
to result in a significant expansion of native wetland vegetation is all of the project areas.
Exotic/invasive species and weed contro~ measures will be implemented for 5 years after the initial
mitigation/revegetation installation, or until the ultimate success criteria have been_ achieved in
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accordance .with the Guidelines for Habitat .Creation and Restoration (City of Carlsbad, 2009)
and this HMMP. Remedial actions and/or adaptive management measures may be required to
promote project success. The suppression of exotic/invasive species and weed growth and their
reduction over the extended maintenance period will allow establishing native vegetation to
become dominant over the non-native plant species throughout the project site. The newly
established vegetation will have a positive effect on many aspects of the biological and
hydrological functions and values including, sediment entrainment, moderation of _ flow
velocities, carbon storage, shade that will suppress non-native seedling recruitment and moderate
water runoff temperatures, and enhancement of wildlife resources. Trash and debris removal will
occur as part of the maintenance regime during the maintenance and monitoring period.
4.2 Existing Resource Impact Avoidance
Per the City's HMP, the use of heavy equipment, equipment that produces noise greater than 60
decibels, equipment that produce~ a large amount of dust, and removal of trees shall be
conducted outside of the raptor and migratory bird breeding season (February 15---September 15)
with no vegetation clearing allowe_d within occupied coastal California -gnatcatcher habitat within
the breeding season (March 1 and August 15). If this schedule cannot be met, it is recommended
that a qualified biologist inspect the ' trees for nests prior to construction or non-routine
maintenance. If an active nest is found, no impacts shall be allowed within 500 for all listed
species and 300 feet for non-listed species until all young have fledged.
Project construction and maintenance shall comply with the HMP -Section F, Preserve
Management, and specifically the Recreation and Public Access guidelines contained therein on
pages F-11-F-14.
4.3 Site Access and Protection
Public access is allowed within the Preserve, and it is anticipated that pedestrians will be
passing near the area regularly. For the duration of boardwalk: and mitigation installation, it is
anticipated that all trails in the immediate area under construction, will be closed until
boardwalk: and mitigation installation is complete. Temporary trail closure sign.age will be
provided and installed by the City of Carlsbad, and/or their designated Preserve Manager. The
limits of the mitigation/restoration areas will be delineated with temporary orange construction
fencing and sign.age to protect the sites during the plant establishment period. The Restoration
Ecologist shall inspect all construction fencing prior to construction to avoid unauthorized
impacts. This temporary fencing will remain in place and be maintained by the Habitat
Restoration Contractor through the fust growing season, and longer if necessary as
recommended by the Restoration Ecologist.
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4.4 -Erosion Control and Best Management Practices
To minimize the potential for loss of soils from the sites during construction and the plant
establishment period, silt fences, fiber rolls, and construction fencing may be incorporated into
the best management practices (BMPs) based on the Storm Water Pollution Prevention Plan
(SWPPP) and Restoration Ecologist's recommendations. Construction BMP's would be
implemented according to Appendix B of the Final MHCP Subarea Plan, Volume II.
Project fencing and BMPs affected/lost due to storm flow events will be replaced, modified, or
not replaced at the discretion of the Restoration Ecologist.
4.5 Grading and Site Preparation
Site grading will be conducted in the areas designated as wetland creation only. Grading will
lower the elevation of existing disturbed habitat (upland) adjacent the existing ACOE/CDFG
jurisdictional wetland, establish inlet and outlet elevations and establish appropriate flow ' .
gradients across the site. Creation topography shall be established based on reference spot
elevations collected in the adjacent ACOE/CDFG jurisdictional wetland areas to ensure correct
elevations. Elevations an1 transitional gradients will be established to accept flood inundation
from Calavera Creek and promoting creek flushing and limiting excessive ponding, which may
lead to hyper-saline conditions.
The wetland creation sites will be graded down per project plans and specifications, in order to
access groundwater for planted vegetation, as well as to create the target hydrologic regime. The
site will be graded to allow seasonal inundation. It is anticipated that the predoniinant hydrology
established on site will be through established secondary channels and thrqugh the expansion of
the active flood zone.
No import soil is anticipated to be necessary for implementation of the restoration plan. Most of
the ·soil removed to create the jurisdictional wetlands will be used on site to fill in eroded areas,
elevate the adjacen{ trail in upland areas, and/or it will be exported to an approved off-site
disposal area. Grading will be accomplished to create the optimum conditions for wetland
hydrology and wetlands vegetation community development.
The Restoration Ecologist will observe rough and final grades to assess whether the grading
complies with the intent of the project design and are adequate to support the target
vegetation for the· area. ·Toe Restoration Ecologist will periodically monitor the site
preparation and grading procedures to verify that they stay_ within the established limits,
minimize impacts to existing wetlands and native vegetation, and comply with any applicable
resource agency permit conditions.
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Excessive soil compaction and/or limited soil fertility may require areas to be mechanically
prepared (i.e., ripped and tilled), primarily in areas impacted from recreational traffic. Treatment
may require portions of the restoration and compaction areas to be mechanically cross ripped to a
depth of between 3 and 6 inches. All compacted trail areas underlying the proposed boardwalk
footprint (i.e. permanent impact areas, will be ripped/tilled to help fill in eroded areas and to
assist with natural plant recruitment under the boardwalk where possible. Graded areas shall be
cross-ripped to allow for application of soil amendments.
Soil fertility deficiencies may require the ripped soil to be treated with the appropriate soil
amendments as recommended by soils analysis. Following grading and site preparation/soil
manipulation, the surface of the soil shall be fine graded to best facilitate the seed application
and mimic the adjacent natural upland topography. Soil samples shall be collected from all
creation, restoration and enhancement areas (maximum 3) _and submitted for soil analysis to
an approved soil laboratory for soil fertility and agricultural suitability analysis. Soil
amendments or fertilizers may be incorporated into the soil, container plant backfill mix or
hydro seed slurry mix, based on the results of the laboratory analysis and 'per the Restoration . .
Ecologist's final recommendations.
4.6 Hydrology
Wetland creation is dependent on establishing an appropriate site hydrology. This will be
achieved by excavating the areas down to an elevation that will allow the seasonally high stream
flows and flood inundation from the slow moving Calavera Creek to enter into the creation areas.
To support the establishment of wetland vegetation communities, a hydraulic surface inlet and
outlet will be created to provide opportunity for seasonal inundation to flood the northeastern
creation site and the grade will be uniformly lowered at the central creation site to accept flood
flow inundation during high water conditions (Figure 5).
Excavation within the site is expected to. ensure that the entire mitigation site will have sub-
surface groundwater or capillary fringe soil moisture present within the root zone of the plants in
all vegetation community types. A suitable gradient a_cross the length of northeastern creation
area will allow flow through the site and back into the main, existing creek channel.
4.7 Irrigation System Installation
Due to the unpredictable nature of southern California rainy seasons, and to. facilitate plant
establishment, supplemental irrigation and/or hand watering will be required for the wetland
creation and enhancement areas. A temporary irrigation .system is recommended for the
northeastern wetland creation site and associated upland buffer zone planting area. Hand
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watering is required for all restoration and enhancement areas along the constructed
boardwalk and adjacent to the upstream trail. Supplemental irrigation and hand watering will
only be used during plant establishment, as the goal of the restoration effort is to create
native, self-sustaining plant communities that can survive on their own over the long term.
Irrigation and hand watering scheduling will • be set to promote deep rooting of plant
materials, with infrequent, long-duration cycles.
The irrigation system for the northeastern wetland creation area and upland buffer zone will be
designed with • above-ground components to facilitate removal once the system is
decommissioned. The system shall remain in place until the vegetation is established and can
survive without supplemental water. The irrigation system will utilize potable water at a local
point of connection. The irrigation system will consist of PVC pipe staked on grade at
approximately 10 feet on-center and at all corners, providing 100 percent coverage of the
northeastern creation area using spray and/or rotor heads where appropriate. Check valves will
be installed to eliminate low-head drainage where necessary. All irrigation will be installed by
the Habitat Restoration Contractor and per· the final revegetation construction documents. All
irrigation components shall be .removed from the site prior to the end of the five-year period and
prior to receiving mitigation sign-off by the ACOE.
Due to limited access and limited water sources within the Preserve, hand watering is
recommended for the restoration and enhancement areas located immediately adjacent to
Boardwalk construction. The Habitat Restoration Contractor shall be responsible for hand
watering all con~iner plants installed in these areas until adequately established. It is anticipated
that the high water table and extended periods of soil saturation will facilitate successful
establishment of planted container plants and seed with limited supplemental watering.
4.8 Recommended Plant Palettes
A total of four vegetation communities will be established ~n site: SWS, FWM, SCLORF and
DCSS. In general, FWM will be located in areas expecting to be frequently inundated and with
soils saturated the majority of the year. SWS will be located in areas that are expected to have
appropriate and frequent inundation with seasonal saturated soils. SCLORF species will expect
infrequent inundation with the water table close to the surface, with a slight increase in _elevation
above SWS. It will be created through the addition of community-specific species such as
I . sycamores and coast live oaks. The species selected for the each planting palette include those that
are typical for the vegetation community or have been observed within that habitat on site.
After site grading, and irrigation system installation, the planting areas will be prepared and
revegetated with the intended native species. Proposed planting palettes are shown in Tables
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5-9. All container plants, live stakes, and seed shall originate from coastal San Diego or
Orange County to the greatest extent practicable. A combination of above-ground, temporary
irrigation system operation and hand watering will be utilized to establish plants the first 3
years after planting.
Table 5
Coastal Valley Freshwater Marsh Plant Palette (0.11 ac.)
Composition
Botanical Name Common Name Size Spacing (approximate)
Anemopsis ca/ifornica Yerba mansa 1 gal. 3' 45%
Eleocharis machrostachya Pale spike sedge 1 gal. 1.5' 8%
Juncus acutus spp. leopoldii Spiny Rush 1 gal. 4' 30%
Juncus mexicanus Mexican rush 1 gal. 1.5' 9%
Scirpus ca/ifornicus California bulrush 1 gal. 1.5' 8%
Total 100%
Table 6
Southern Willow Scrub Plant Palette (0.20 ac.)
Composition
Botanical Name Common Name Size Spacing (approximate)
Canopy Species
Baccharis sa/icifo/ia Mulefat 1 gal. 6' 15%
Platanus racemosa Western sycamore 1 gal. 20' 30%
Salixexigua Narrow -leaved willow cutting 6' 10%
Salix goodingii Black willow cutting 6' 5%
Salix lasiolepis Arroyo willow cutting 6' 25%
Total 85%
Understory Species
Carex soissa San Dieqo sedqe 1 qal. 3' 9%
Iva hayesiana San Dieqo marsh elder 1 qal. 4' 25%
Juncus acutus soo. /eopoldii Spiny Rush 1 qal. • 3' 8%
Rosa californica California wild rose 1 qal. 4' 20%
Rubus ursinus California blackberry 1 gal. 4' 23%
Total 85%
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Quantity
228
155
88
193
155
819
Estimated
Quantity
33
7
27
14
55
136
83
134
71
105
136
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Table 7
Southern Coast Live Oak Riparian Forest Plant Palette (0.20 ac.)
Composition Estimated
Botanical Name Common Name Size Spacing (approximate) Quantity
Canopy Species
Baccharis sa/icifolia Mulefat 1 gal. 6' 25% 48
Platanus racemosa Western sycamore 1 gal. 20' 15% 3
Quercus agrifolia Coast live oak 1 gal. 18' 50% 11
Total 90% 62
Understory Species
Juncus acutus spp. leopoldii Spiny Rush 1 gal. 3' 9% 78
Muh/enbergia rigens ·Deer grass 1 gal. 3' 19% 165
Ribes speciosum Fuschia-fiowered gooseberry 1 gal. 4' 5% 24 .
Rosa californica California wildrose 1 gal. 4' 18% 88
Rubus ursinus California blackberry 1 gal. 4' 22% 105
Total 73% 460
Table 8
Southern Coast Liv€: Oak Riparian Forest/Southern Willow Scr~b Seed Mix (0.40 ac.)
Botanical Name Common Name Pure Live Seed Rate#/acre
Ambrosia psilostachya Western ragweed 6 2.0
Anemopsis ca/ifornica Verba mansa 50 4.0
Artemisia douglasiana Douglas mugwort 10 2.0
Artemisia palmeri San Diego sagewort 10 1.0
Carex spissa San Diego sedge 70 2.0
Eleocharis macrostachya Pale spike rush 60 2.0
Plantago ovata1 Wooly plantain 85 6.0
Leymus triticioides Wild rye 80 4.0
Juncus bufonius Toad rush 60 3.0
Juncus mexicanus Mexican rush TBD 2.0
Muh/enbergia rigens Deer grass 60 1.0
Total 29.0
Note: All hydroseed mixes shall include seed mix indicated in pounds per acre and virgin wood cellulose fiber mulch at 2,000 pounds per acre.
1 Erosion control and nurse crop species.
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Table 9
Diegan Coastal Sage Scrub Seed Mix (0.05 ac.)
Botanical Name Common Name Pure Live Seed Rate#/acre
Artemesia californica California sagebrush 10 3.0
Bromus carinatus1 California brome 85 1.0
Castilleja exserta spp. exserta1 Purple's owl clover 25 0.5
Encelia catifornica California sunnower 24 2.0
Eriophyllum confertifolium1 Golden yarrow 25 2.0
Eriogonum fasciculatum Flat-topped buckwheat 10 5.0
Lasthenia californica1 California goldfields 50 0.5
Lotus scoparius Deer weed 85 3.o·
Lupinus succulentus1 Arroyo lupine 90 1.5
Mimu/us aurantiacus sticky monkey Hower 2 2.5
Nassela lepida Foothill needle grass 65 2.0
Nassela pulchra Purple needle grass 75 2.0
Plantago ovata1 Wooly plantain 85 5.0
Salvia mellifera Black sage 40 2.0
Sisyrinchium bellum1 Blue-eyed grass 80 1.5
Total 31.5
Note: All hydroseed mixes shall include seed mix indicated in pounds per acre and virgin wood cellulose fiber mulch at 2,500 pounds per acre.
1 Nurse crop species.
It is anticipated that the seed mixes will be installed through a combination of hydroseeding for
accessible areas and hand seeding in inaccessible areas. The recommended seed mixes contain
several common, native annuals to serve as nurse crops, plus perennial native species that are
expected to provide the majority of the cover for the DCSS restoration areas and contribute to the
herbaceous understory for the FWM/SWS/SCLORF mitigation areas. Other native species are
expected to volunteer into the area from adjacent habitat areas and will contribute to cover,
species richness, and habitat value as well over time.
A seed supplier specializing in native species, such as S&S Seeds in Carpentaria, Recon in San
Diego, or an approved equal, shall be contracted with to supply the necessary seed. The seed
source should be from the local San Diego coastal region.
Appropriate timing of the seed application may decrease the need for supplemental watering and
will improve plant establishment. It is anticipated that the construction activities will be
completed prior to the rainy season. Seeding at the beginning of the rainy season is ideal. Should
hydroseed fail to germinate within a 120-day plant establishment period, the Restoration
Ecologist may recommend reapplication of seed in the non-performing areas.
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4.9 Planting Materials
After grading and irrigation installation, container plants and cuttings will be installed followed
by hydroseeding, as descnbed above. The Restoration Ecologist will inspect and approve all
container plants, cµttings and labels for each hydroseed mixture prior to application. The .
contractor awarded the installation for the restoration program shall provide copies of the seed
mix, listing species, quantities, as well as percent of germination rates that are to be provided by
the intended seed vendor. Actual seed tags shall be provided at the time of installation.
Standard planting procedures will be employed for the installation of the container stock.
Planting holes shall be approximately twice the width of the rootball and as deep. If dry soil
conditions exist at the time of plant installation, planting holes will be filled with water and
allowed to drain immediately prior to planting. Backfill soil will contain no amendments and
fertilizers unless shown in the construction documents, recommended by soil test results and/or
by the recommendation of the project biologist.
The cuttings will be it;tstalled in the southern willow scrub creation and enhancement areas. The
cuttings will be collected from the surrounding riparian habitat. Cuttings will be 12-18 inches
long and one-half inch to one inch in diameter. The cuttings will be inserted approximately two-•
thirds their length into the soil.
Hydroseed shall be applied in a hydromulch slurry containing the 1specified seed mix, as well as
the other specified slurry mix components including virgin wood cellulose fiber mulch, at the
specified rates. Fertilizer shall ·be included in the hydromulch slurry mix based on the results
from soil testing and recommendations from an approved soil testing laboratory. The Restoration
Ecologist will approve all final fertilizers and amendment applications prior to installation.
4.1 O Time Lapse
It is expected that the mitigation areas will require approximately five years to develop into a
system that is in a state of equilibrium capable of resisting invasion by weeds ~d exotic/invasive •
species. Within approximately the first three years, the created, restored and enhanced wetlands
should become self-sustaining, and able to survive on natural rainfall and creek inundation to
allow the areas to survive without the need for supplemental irrigation or hand watering. In order
to help assure sufficient plant establishment, five years of maintenance and monitoring are
planned to ensure that the mitigation areas develop into the intended riparian vegetation
communities and are sufficiently established to survive on their own, thereafter.
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4.11 Preliminary Schedule
The mitigation program outlined herein, is contingent upon the approval by the ACOE, CDFG,
and RWQCB. Upon appropriate approvals, implementation of the mitigation program is
anticipated to be implemented according the schedule in Table 10.
Table 10
Proposed Implementation Schedule
Implementation Tasks Schedule
Main Boardwalk Installation, Grading (creation areas) and Site Late Fall /Early Winter of 2012
Preparation (restoration and enhancement areas)
Irrigation To be installed after initial weed removal (Fall 2012).
Discontinued by the end of Year 3 (Fall 2015) and
removed/abandoned at the end of Year 5 (Fall 2017).
Container Planting Following completion of site prep., Boardwalk installation
(Fall/Winter 2012.
Hydroseed and hand seed application Fallowing container planting (F alVWinter 2012).
Initial Establishment Period: Assessment of Installation, Seed Monthly during initial 120-day period following
Germination, and Plant Establishment. hydroseeding and container plant installation (Fall/Winter
2012 -Spring 2012).
Site Maintenance Five years. Bi-monthly during Year 1 and on an as-needed
basis during Years 2-5, based on biological monitoring and
Biologist's recommendations. (Spring 2013-Fall 2017).
Long-term Biological Monitoring Qualitative monitoring bi-monthly during Year 1, following
successful completion of initial (120-day) maintenance period,
and quarterly during Years 2-5. Annual quantitative monitoring
(transects) in Years 3-5 (Spring 2013 -Fall 2017).
Final Sign-Off End of Year 5 (or earlier if agreed to by agencies). Based upon
achievement of Year 5 standards (FalVWinter 2017)
4.12 Initial Establishment Period
During the initial (120-day) plant establishment period, following the hydroseed and hand seed
applications and container plant installation, the Restoration Ecologist will monitor site
conditions, including seedling germination, container plant survival and soil erosion, to
determine if the plants are becoming adequately established and to verify whether the hydroseed
application has been successful. If the hydroseed application has been successful and adequate
germination occurs, then rapid seedling emergence should preclude the need to install additional
erosion control devices. Potential remedial actions, if germination is not sufficient, include
reseeding, installation of additional erosion control devices, and follow-up weed control.
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4.13 As-Built Plan
Upon successful completion of the installation and the initial 120-day plant
establishment/maintenance period, the Restoration Ecologist shall submit a report to the ACOE,
RWQCB, and CDFG describing the completion of the installation phase and describing the "as-.
built" status of the mitigation project. The report shall include a reduced set of construction
drawings showing the final "as-built'' locations of the irrigation system and the final limits of the
revegetation areas. A'GPS generated map shall be submitted if possible. Photographs shall also
be included to document the site at the completion of the installation monitoring period, i.e., end
of initial 120-<lay maintenance period.
4.14 CosfEstimate •
It is estimated that the initial cost for installation and initial maintenance of the
mitigation/revegetation effort, for the total 0.56-acre area, will cost approximately $97,500. This
cost estimate includes the installation of temporary protective fencin·g, grading, weed control,
site preparation, signage and fencing, irrigation, hydro-seed and container plant installation, and
plant establishment maintenance for the first 120-days following installation. Costs do not
include the cost of the actual boardwalk i.Iistallation.
Long-term maintenance costs for the . proposed five-year maint~nance period would total
• approximately $27,500 including the costs associated with the weed control, irrigation, hand
watering and site maintenance. The total cost for the entire mitigation and monitoring program is
· estimated to be $125,000 through the end of the five-year period.
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5.0 MAINTENANCE PLAN
All mitigation areas will be subject to the requirements specified in this plan. The City will be
responsible for ensuring the maintenance and monitoring of the mitigation sites until the site
meets established performance standards.
Because the goal of this plan is to reestablish natural vegetation communities that can support
themselves with litt_le or no maintenance, the primary effort of the maintenance plan is
concentrated in the first few seasons of plant growth following the creation and enhanc.ement .
efforts, when weeds can easily out-compete native plants. The intensity of the maintenance
activity is expected to subside each year as the native plant materials become more established .
and as local competition from non-native plants for resources in the restoration areas is •
minimized through control of non-native plants.
5.1 Maintenance Activities
The long-term maintenance period shall begin upon the successful completion of the initial (120-
day plant establishment)·maintenance period and shall last for 5 years. The Habitat Restoration
Contractor shall be responsible for periodic weed/exotic species treatment and removals, trash
and debris removal, irrigation maintenance and adjustment, hand_watering, replacement of dead
container plants/cuttings, fence and signage maintenance, and similar site maintenance functions
during the 5-year maintenance and monitoring period.
5.1.1 .Pest Management
Annual weed and non-native exotic control is expected for the Long-term monitoring period.
The Restoration Ecologist will advise the Habitat Restoration Contractor as to which pest
species to control.
Target weed species include those on the California Invasive Piant Council (Cal-IPC) California
Invasive Plant Inven~ory (Cal-IPC 2006). Additional spe_cies beyond those listed in the Cal-IPC
publication may require control. The Restoration Ecologist will determine any additional species
requiring control. Based on the discretion of the Restoration Ecologist, some innocuous,
naturalized annual weeds that are common to the area but do not normally out-compete or invade
native habitats may be tolerated.
Physical removal of non-native plants, including the roots, may be the best method for those species
for which the root system~ readily be pulled out with the aboveground portions of the plant. These
species will be physically removed before seed-set. If hand removal is possible only after seed-set,
then seed heads will be cut off: bagged, and removed from the site prior to the weed removal.
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Herbicides will be used for the invasive exotic plant species that have root systems that are
impractical to remove or that regenerate from small root fragments. Any herbicide use should be
conducted using methods that minimize effects to adjacent/desirable native species, suc_h as
brush application or spot spraying. Only herbicides registered for aquatic use can legally be used
in locations where they might come in contact with open water.
I Follow-up control measures will likely be necessary for invasive plant species with extensive
root systems that cannot usually be killed with one herbicide application. Follow-up herbicide
treatment should be done at the biologically appropriate time when the recovering plants are still
relatively small and before they have time to regain strength and vigor.
Invertebrate pests, such as snails, slugs, insects, mites, etc., are not expected to be a problem in the
project area but will be controlled by the Habitat Restoration Contractor, if necessary. Vertebrate
pests, such as gophers, ground squirrels, rabbits, rats, voles, etc., may become a problem and will be
controlled by the Habitat Restoration Contractor, if necessary. Plant diseases could become a
problem during the plant establishment period but can generally be prevented or controlled by
cultural measures.
Pest control will be conducted following all applicable laws, regulations, label directions, and
safety precautions. Should the Habitat Restoration Contractor require specific pest control
recommendations, he or she shall consult a licensed pest control adviser. The Habitat Restoration
Contractor shall provide reports of all pest control measures implemented-at the site, including
details of method used, including any pesticide applications. Copies of any written
recommendations shall also be provided. The Habitat Restoration Contractor shall provide copies
of all pesticide use reports to the appropriate entity to document pesticide use and reporting.
5.1.2 Irrigation System and Hand Watering
The irrigation system shall be checked regularly to ensure proper operation and adequate
coverage of the wetland mitigation and upland restoration areas. Problems with the system
shall be repaired immediately to re.duce potential plant mortality. The frequency and duration
of irrigation applications and hand watering shall be adju~ted seasonally by the maintenance
contractor in coordination with the Restoration Ecologist to meet habitat needs. The
irrigation system will be used as necessary during the first 3 years of the long-term
maintenance and monitoring period, and will be terminated no later than the end of year thre~
to ensure that the site is self-sustaining for at least two years (i.e., two summers) prior to
final sign-off from the resource agencies. All above ground components shall be removed
completely from the mitigation area by the end of the fifth year.
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Portions of the· mitigation site not within the irrigation zone shall require hand watering on a
regular basis until container plants have established to self-sustain themselves on existing surface
water, the existing water table and seasonal rainfall It is anticipated that non-irrigated areas shall
require hand watering on a regular basis throughout the initial Plant Establishment Period and
Year One of the long-term maintenance period, and on a periodic basis during the spring,
smnmer and fall of Years Two and Three. Any container plants or cuttings exhibiting unexpected
and excessive drought stress shall receive an increase in hand watering until health returns. All
mortality attributed to insufficient watering shall require in:-kind plant replacement at the cost of
the Habitat Restoration Contractor. Hand watering and irrigation is expected to be discontinued
at the end of Year Three.
5.1.3 Trash Removal
Trash and debris will be removed from the mitigation areas by hand during maintenance visits.
Trash and debris consist . of all man-made materials, equipment, or debris dumped, thrown,
washed, blown, and left within the .mitigation areas. Trash and inorganic debris washed or blown
onto the mitigation sites will be removed regularly'. Deadwood and leaf litter of native trees and
shrubs will not be removed. Downed logs and leaf litter provide valuable micro-habitats for
invertebrates, reptiles, small mammals, and birds. In addition, the decomposition of deadwood
and leaf litter is essential for the replenishment of soil nutrients and minerals.
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6.0 MONITORING REQUIREMENTS
Monitoring of the·restoration areas has a three-fold purpose: (1) To monitor the progress of the
mitigation area by assessing quantitative measurements, (percent native and non-native coverage
via transect data collection in years 3-5) with the performance guidelines; (2) to direct and
monitor the maintenance activities through qualitative (visual observation and evaluation)
methods and determine remedial actions in a manner that ensures that appropriate maintenance
occurs in a timely manner; and (3) to recommend and· implement adaptive management
strategies that promote successful attainment of performance criteria The monitoring shall be
performed by a qualified biologist or habitat restoration specialist (Restoration Ecologist).
The Restoration Ecologist shall be responsible for monitoring the_ activities of the Habitat
Restoration Contractor during boardwalk construction, during site clearing and grading operations
to assure protection of existing wetland areas that are to remain and be protected, as well as during
initial weed control, finish grading, irrigation installation, container planting, hydroseed
application, and monthly monitoring during the 120-day plant establishment/maintenance period
The monitor shall also provide bi-monthly monitoring during year one of the maintenance and
monitoring period, and quarterly monitoring in years 2-5 of the 5-year maint~ce and
monitoring period. The Biological Monitor will communicate and co-ordinate with the Habitat
Restoration Contractor to assure the timely performance of project activities. The Biological
Monitor shall submit an "As-Built'' report within 60 days of completion of the installation period
(end of 120-day period), and Annual Reports each year by the anniversary date during the five-
year monitoring period, to the City, ACOE, CDFG, and RWQCB.
6.1 Performance Standards
Performance standards include minimum growth, survivorship, and vegetative cover target
criteria, as well as target functions and values based on established functional wetlands
standards. A combination of assessment methods are important to understanding the ecological
functioning and, thereby, the success of the miti~on. Performance guidelines outlined -herein
follow the requirements of the performance standards outlined in the City of Carlsbad developed
Guidelines for Habitat Creation and Restoration (2009) and include modifications/additions
requested by the ACOE.
6.1.1 Perfonnance Standards
The performance guidelines shown in Table 11 are proposed to direct the evaluation of the
mitigation area The primary mitigation goal for this project is to create and enhance wetland
vegetation. Therefore, the following restoration coverage guidelines are used as a gauge to
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determine whether adequate native plant growth (percentage cover) and weed/exotic control is
present to allow for adequate plant growth and establishment. The performance guidelines are
viewed as interim project objectives designed to achieve the final mitigation goals. If mitigation
efforts fail to meet the performance guidelines in any one year, then the Biological Monitor shall
recommend remedial actions to be implemented the following year to enhance the project to a
level of conformance with the original guideline. Each monitoring report shall include an
assessment of the quantitative and qualitative performance standards in order to document
progress of the mitigation site.
Table 11
Performance Guidelines for Created and Enhanced Wetlands Vegetation Communities
Criteria Year1 Year2 Years31 Year41 Year51
Percent Native Cover 30% 40% 60% 75% 90%
Container Plant and Cutting Survival2 100%/60% 90%/80% 80%/80% 80%/80% 80%/80%
Maximum Annual Non-Native/Weed Cover 20% 15% 10% 5% 5%
Maximum Perennial Non-Native/Exotic Cover 5% 0% 0% 0% 0%
Average Height of Wetland Tree Species in 4 ft. 5 ft. 6 ft. 7ft. 8 ft.
Feet (Willows, Sycamores, Oaks)
0 Percentages based upon transect data in years 3-5, visual estimates only in years 1 and 2.
1 Container Plan Survival/Cutting Survival. Naturally recruiting native species may be counted as credit for replacement of dead container or
cutting stock. Any quantity of dead plants exceeding this percentage shall require replacement planting, unless the project meets or
exceeds the total native cover performance standard. •
Note: It is presumed that the unaccounted for percentage of cover will be unvegetated, or bare ground.
6.1.2 Functional Wetlands Standards
The following general site characteristics must be met by the end of the 5-year maintenance and
monitoring period.
Site Must Meet All Three Wetland Parameters
The wetland creation and restoration areas under the jurisdiction of the ACOE must meet the
definition of a 3-parameter ACOE-jurisdictional wetlands by the end of the 5-year maintenance
and monitoring period. A delineation of the wetland creation areas will be required prior to
resource agency sign-off from the ACOE and RWQCB. If it is determined that the wetland
creation areas meet the vegetation and hydrology criteria for a ACOE wetland, but are lacking
hydric soils, the ACOE may waive, at their discretion, the need to obtain hydric soils prior to sign-
off if the site is progressing towards hydric soils and will likely become hydric in the near future.
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Site Must Be Self-Sustaining
The mitigation area must be self-sustaining (i.e., able to survive on their own without artificial
support) by the end of the 5-year maintenance and monitoring period~ Determination of self-. '
sustainability will be the presence of natural growth cycles and healthy wetlands vegetation that
has not been irrigated in the preceding two years prior to the end of the 5-year maintenance and
monitoring period.
Site Must Show Evidence of Natural Recruitment
The mitigation area must show evidence of natural recruitment of native wetlands and/ or riparian
species within the mitigation area. This means naturally occurring native species colonize the site
in addition to the originally planted container plants or applied seed.
Site Must Show Evidence of Wildlife Use
The mitigation area must exhibit s_igns or evidence of wildlife use during the final two years
of monitoring.
Habitat Contiguity
The mitigation area must con~ wetland vegetation that is contiguous with upstream and
downstream wetland/riparian habitats. Habitat connectivity and appropriate habitat linkages will
provide nesting and foraging habitat for wildlife species.
Hydrologic Regime of Riparian Zone
The mitigation area must contain evidence of natural hydrologic riparian processes such as
overbank flow, repeated inundation, scour, or deposition (i.e., wrack lines).
Micro-and Macro-Topographic Complexity
The mitigation area must contain evidence of micro-_ and macro-topographic complexity such as
pits, ponds, hummocks, bars, rills, rock or boulders, bars, braiding, backwaters, and terraces.
Topographic complexity will provide greater flood flow modification and flood storage functions.
Biogeochemical Processes
The mitigation area must contain woody debris, leaf litter, or detritus. Expansion of riparian
areas will increase natural water quality functions such as uptake of nutrients and toxicants and
sediment trapping.
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6.1.3 Qualitative Monitoring
Documentation of native vegetation coverage, weed presence, and site progress will be collected
during monitoring visits to be used in the annual monitoring report. Qualitative monitoring will
also be conducted to assess native plant vigor and development, seedling recruitment from native
seed application and natural sources, soil moisture content, presence/absence of plant pests or
diseases, .erosion and/or drainage conditions on site, presence/absence of non-native or invasive
plant species, trash or debris accumulation, wildlife presence/absence, and status of project
fencing. All qualitative monitoring visits to the mitigation areas will be documented with a site
observation monitoring report, which will be forwarded to the Habitat Restoration Contractor
and the City. Any project deficiencies will be noted in the monitoring report, with accompanying
recommendations for maintenance and/or remedial actions.
6.1.4 Quantitative Monitoring
Quantitative monitoring via data collection will be conducted to determine native species cover
and composition and total non-native species cover BJ?,d composition.
Quantitative monitoring will be conducted by establishing permanent vegetation 25-meter
transects within the mitigation areas at random locations by the Restoration Ecologist at the end
of Year Two. These transects will be utilized during years three -five to help determine
achievement of the yearly performance standards and compliance with agency and City
standards. Permanent photo-documentation stations will also be established along each transect
to record the progress of the mitigation site and graphically record plant establishment over the
5-year period.
Transects will be sampled using the point-intercept method. A transect tape will be run between
two posts, and vegetative intercept line will be visually projected above and below the tape at
every half-meter mark. Transects will be no longer than 25 meters, but may vary in length based
upon the location, and size of the individual restoration area. Each hero or shrub that intercepts
the projected line will be recorded by species. In addition, all plant species present within the 5-
meter-wide "species richness" portion of each transect will be recorded by species. All data will
be utilized to determine total percent plant cover, percent native cover," percent non-native cover,
and overall species richness and diversity. Quantitative monitoring will be conducted once
annually beginning in Year Three and extending through Year Five of the Restoration Project.
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7 .0 REPORTING
Annual monitoring reports will be submitted to the City, the resource agencies and the
Restoration Contractor during the 5-year maintenance and monitoring period of the proposed
project. The monitoring reports will describe the existing conditions of the project areas derived
from qualitative field observations and quantitative vegetation data collection. The reports will
provide a comparison of annual success criteria with field conditions, identify all shortcomings
of the project, and recommend remedial measures necessary for the successful completion of the
restoration project. Each yearly report will provide a summary of the accumulated data. Annual
reports also will include:
• A list of names, titles, and companies of persons who prepared the annual report and
participated in monitoring activities
• Prints of biological monitoring photographs, as appropriate
• Maps identifying monitoring areas, planting zones, and weed removal areas, as appropriate
• Quantitative data from transect measurements in years 3 through 5 of the restoration effort.
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8.0 CONTINGENCY MEASURES
If the final su~ criteria are not met, the Restoration Ecologist and the City will prepare an
analysis of the cause(s) of failure within the appropriate annual report and, if determined necessary
by the resource agencies, propose contingency measures, including remedial actions and/or
adaptive management strategies, to address the problem. Toe City's maintenance and monitoring
obligations will continue until contingency measures are nego~ated and implemented to bring the
restoration site into compliance with the established standards.
8.1 Adaptive Management
Adaptive management will be implemented in the event of unforeseen or unpredictable
circumstances. Due to the complexity and dynamic nature of ecosystems, and anticipation of
unexpected events or outcomes, a flexible resource management plan is desirable.
For purposes of this mitigation project, adaptive management is defined as a flexi"ble, iterative ,
approach to the long-term management cif biological resources that is directed over time by the
results of ongoing monitoring activities and direct observation of environmental stressors that are
producing adverse results within the restoration areas. Adaptive management will include the
utiliz.ation of regular qualitative assessments and rapid qualitative assessment data gathered in
the field prior to and during the restoration effort to assess the health and vigor of vegetation
communities within the restoration areas. Rigorous and consistent monitoring is key to effective
adaptive management to ensure that the decisions regarding future management are based on
accurate assessments of the status of the resomces being managec;l. Following an· event that
causes damage to all or . part of a restoration area, the data will be used in part to drive
management considerations for repair C?f the damaged areas.
It is the intent of the adaptive management strategy in this HM:MP to intervene only as necessary
to help ensure the conservation of the functions and ~rvices of the mitigation sites and the
conservation of native vegetation communities and individual native species within the
mitigation sites. Remedial measures will only be implemented if it is determined, in consultation
between the City, the Restoration Ecologist, and the resomce agencies, that there is a "risk to the
persistence of the functions and services, native vegetation, or native species on site. Achieving
the key goals of mitigation completion and establishment o±; self-sustaining vegetation
communities will be the focus of adaptive management decisions. Individual environmental
stressors are discussed below, along . with an anticipated range of management responses to
correct damage that may occur to the mitigation areas.
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8.1.1 Herbivory
Some grazing and browsing by native mammals is expected to occur within the mitigation areas.
The plant palettes for each vegetation comm.unify have been designed to accommodate a
moderate level of plant browsing. If browse levels should become. elevated (i.e., if significant
plant mortality and cover reduction occurs) as indicated by qualitative or quantitative monitoring
of the mitigation sites, remedial measures may b_e recommended. _Browse guards (plastic fencing,
cages or tree shelters) may be installed around the base young shrubs in affected areas to reduce
plant mortality. In addition, remedial planting or seeding may be necessary depending upon the
stage of the restoration effort.
8.1.2 Sediment Loss and Erosion Issues
Sediment loss and erosion issues are not a major concern, as wetland mitigation areas are mostly
located along the periphery of the drainage, which is subject to lateral flood inundation rather
than rapid creek velocities. Erosion may be a concern in areas if abnorma:l storm events occur
and increase creek velocities through the mitigation area, causing excessive scour and sediment
deposition. The Diegan coastal sage scrub restoration area is not anticipated for erosion, as it is
located on gentle grades. All mitigation areas will be monitored regularly, and if issues develop,
recommended remedial actions will be recommended to minimize sediment loss. Such measures
may include the installation of silt fencing, straw wattles, gravel bags or other materials to
prevent erosion.
8.1.3 Drought
Seasonal drought is a normal annual cycle in San Diego County, and all plant palettes have been
designed with drought-tolerant plant species that are capable of withstanding seasona:l
fluctuations in available moisture. However, an extended drought could potentially occur,
including low season.a:! rainfall and prolonged hi~ temperatures that may negatively affect the
restoration areas ( e.g., lower native cover, higher plant mortality, increased potential for pest
infestations on site, etc.). Irrigation (including hand watering) will reduce or eliminate the effects
of drought on container plants and seedlings during the first 3 years of the restoration effort. Any
remedial options that may be necessary after 3 years from the installation date will likely require
an additional period of site irrigation to relieve plants from drought stress and/or provide for new
seed growth. All irrigation components will be left in place until the end of year five in case
remedial seeding and/or container planting is required at a later project date. If the irrigation
system is required at a later date, it should be used only as necessary (i.e., periodic watering
versus regular daily watering). After successful completion of the restoration effort, the irrigation
system will be removed from the site.
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9.0 COMPLETION OF MITIGATION
9.1 Notification of Completion
When the City and Restoration Ecologist believe that the final Year Five performance standards
have been met, either before, or at the end of the 5-year maintenance and monitoring period, they
shall then notify the ACOE, RWQCB, and CDFG upon submitting the annual report and request
formal acceptance of the site 8.11d release from the permit conditions and any bonds or letters of
credit that may have been placed on the project. Release of mitigation obligations before Year 5
will only be considered if Year 5 performance criteria have been met for 2 consecutive years.
9.2 Agency Confirmation
Written acceptance and/or concurrence from the agencies shall be solicited in order to signify
and document completion of the mitigation obligations.
Following receipt of the notification of completion from the City, representatives from the ACOE,
RWQCB, and CDFG may visit the site to confirm the completion of the mitigation effort.
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10.0 SITE PROTECTION INSTRUMENT (LONG-TERM MANAGEMENT)
The primary focus of this IDv.fMP is on the successful restoration and compensation/mitigation
for impacted vegetation communities. The overall management goals of the restoration program
are designed to manage the restoration sites such that none of the intended functions and values
(i.e., services) of the sites are lost over time, and so that the presence of native habitats and
individual native species are conserved.
The Lake Calavera Project site is located within a proposed hardline conservation area of the. City's
HMP preserve system and receives the same conservation status as existing hardline areas and thus is
designated as open space. Once concurrency from the agencies is provided to signify that the
mitigation obligations have been completed, the restoration area will be handed over to the preserve
manager for Lake Calavera preserve for long term management maintenance and monitoring in
accordance with the City's HMP and Open Space Management Plan. Appropriate funding in order to
maintain the site will be provided to the Preserve Manager by the permittee.
A draft declaration of restrictive covenant has been written for the preserve and approved by the
City. This restricted covenant is currently under review with ACOE le~al staff. An ACOE
approved deed restriction, or other form of protection deemed appropriate by the ACOE, will be
placed over the mitigation site, to be provide protection of the site in perpetuity.
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11.0 REFERENCES
73 FR 19594-19705. Final rule: "Compensatory Mitigation for Losses of Aquatic Resourc·es."
April 10, 2008.Merkel & Associates, Inc. 2009. Lake Calavera Trails Biological
Resources Report. Carlsbad, CA. January 28.
AMEC Earth & Environmental, Inc. and Conservation Biology Institute. 2003a March. Volume I,
Final .MHCP Plan. Administered by SANDAG for the Cities of Carlsbad, Encinitas,
Escondido, Oceanside, San Marcos, Solana Beach, and Vista. Prepared for the Multiple
Habitat Conservation Program. 9 Sections + appendices.
AMEC Earth & Environmental, Inc. and Conservation Biology Institute. 2003b March. Volume II,
Final MHCP Plan, Biological Analysis and Permitting Conditions. Administered by SANDAG
for the Cities of Carlsbad, Encinitas, Escondido, Oceanside, San Marcos, Solana Beach, and
Vista. Prepared for the Multiple Habitat Co11Servation Program. 5 Sections+ appendices.
Bowman, RH. 1973. Soil Survey of the San Diego Area, California, Parts I and II. USDA Soil·
Conservation Service and University of California Agricultural Experiment Station.
Cal-IPC (California Invasive Plant Council). 2006. California Invasive Plant Inventory. Cal-IPC
Publication 2006-02, California Invasive Plant Counc_il: Berkeley, California.
http-J/www.cal-ipc.org/ip/inventory/pdf/Inventory2006.pdf.·
City of Carlsbad. 2004. Habitat Management Plan for Natural Communities in the City of Carlsbad.
City of Carlsbad. 2009. Guidelines for Habitat Creation and Restoration, City of Carlsbad.
City of Carlsbad. 2010. Lake Calavera Trails Master Plan, City of Carlsbad.
CNPS (California Native Plant Society). 2010. Inventory of Rare and Endangered Plants (online
y(fition, v7-09b). California Native Plant Society. Sacramento, California.
http-J/www.cnps.org/inventory.
Holland, R.F. 1986. Preliminary Descriptions of the Terrestrial Natural Communities of
California. Nongame-Heritage Program, California Department of Fish and Game.
Hickman, J.C., editor. 1993. The Jepson Manual, Higher Plants of California. University of
California Press, Berkeley. 1400pp.
USFWS (United States Fish and Wildlife Service). 1988. US. Fish and Wildlife Service National
List of Plant Species that Occur in Wetlands: California (Region.
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APPENDIX A
MND Notice of Determination
Mitigation Measures
Page 1 of 8
PROJECT NAME: LAKE CALAVERA TRAILS MASTER PLAN FILE NUMBERS: "-'H=M"-f...,.09""-0"""""'5 ________ _
APPROVAL DATE: ____________ _
The following environmental mitigation measures were Incorporated Into the Conditions of Approval for this project In order to mitigate
Identified environmental impacts to a level of Insignificance. A completed and signed checklist for each mitigation measure Indicates that
this mitigation measure has been compned with and Implemented, and fulfills the City's monitoring requirements with respect to Assembly
Bill 3180 (Public Resources Code Section 21081.6).
Mitigation Measure Monitoring
Type
ijlQL,Q~l~AL. Bl;§Q!JRC~
BI0-1: Mitigation for permanent and temporary Impacts Project-Prior
to upland communities will be mitigated by debiting the to Grading
appropriate acreage at the Lake Calavera Mitigation
Parcel. The Lake Calavera property was Identified In
the City's Habitat Management Plan as a public project
mitigation parcel for municipal projects. The total
acreage available for credit at Its Inception was 186.55
acres. That acreage Is available to mitigate for habitat
impacts from City projects on an acre-for-acre basls
regardless of the type of habitat being Impacted, except
for gnatcatcher occupied coastal sage scrub, southern
maritime chaparral, maritime succulent scrub, and
wetlands. The mitigation provided for each City project
by the Lake Calavera parcel Is tracked and reported on
an annual basis In the City's HMP Annual Report. As of
the end of the last reporting period (October 2008),. a
total of 183.8 acres of mitigation land was still
-available.
The City plans to mitigate for Impacts to gnatcatcher
occupied sage scrub through on-site mitigation and the
preparation of an MMRP, as dascrlbed above. Unbl the
MMRP Is submitted, please refer to the On-site
Ravegatation Recommendations section of the revised
Bloloalcal Resources Reoort (January 28 2009) for a
Expfanatlon of HffdlDP!i
Type • Ptject, orgolng' ourrrue1lve.
Monitoring Dept. = Department, or Agency, reaponalble for moriorlng a partlcular mlllgatlon l1l68mJIB.
Shown on Plana = When mitigation rMll!ll.nl Ill shown on plana, this coklmn wfD be nl:lalad and daied.
Monitoring
L "'"""
Planning
Department
and Biological
Monitor
Verified lmplemantatlon = When mltl!Jation ITl888Ur8 has baoo lmplemenled, this column YAII be lnlllaled and dated.
Romarb "' Area for deeoribklg statue of ongoing mftlgatlon IOOMUre, or for other Information.
RD -Appendix p.
Shown on Verified Rem8'ks Plans I n
Paae 2 of 8
Mitigation Meaaure
tentative map of suitable areas for sage scrub
mitigation as well as appropriate planting material
(attached). The mitigation acreage would Include• a
minimum 1 :1 creation cpmponent within the Immediate
vicinity of occupied coastal sage scrub, with the goal of
creating suitable habitat for the gnatcatcher. This
mitigation plan will Include details regarding grading,
Irrigation design, and planting specifications, as well as
maintenance and monitoring procedures. The plan will
also outline yearly success criteria and remedial
measures should the mitigation effort fall short of the success criter1a. •
Mitigation for lmpa~ to riparian/wetland communities
will be achieved through on-site creation, restoration,
and/or enhancement wlthln the Lake Calavera
Mitigation Parcel. Mitigation shall include a 1 :1 creation
component in accordance with the "no net loss"
wetlands policy in the Carlsbad HMP. Temporary
Impacts will be mitigated at a . 1 :1 ratio through
restoration or enhancement
Expjanation of l::IMlllnqa;
Type "' Project, ongoing, oumulBtlve. .
Monitoring
Tvoe
Monitoring
D ...
llonlortng Dept. " Depllr1ment, or ¾,aoo-/, r88pO!lSlble for monbTJg a particular ~n m&BaUra.
Shown on Plana " Whan mtigallon maeaura 18 ah own on plans, this coomn wtJI be lnBlaled and dalad.
Vertfled mplementzi6on • Whan l1lll\1B1IOn measure has been lmplemanied, this counn v.41 be lnlllal8d and dated. Remarb • Area br deacrlbng ala1J.ls of ongoing mlllgatkm rneeeure, or for other lnfonnallon. •
RD -Appendlx P.
/
\
Shown on Verified
Plans Implementation Remarks
PaQe 5 of 8
MJtlgatlon Measure Monitoring
Tvoe
B10-5: Construct barrier fencing to restrict access to trails Project-
that have been closed. During
Construction
810-6: Maintenance of the Lake Calavera Tralls project will Project-
comply with the Citywide Tran Maintenance Plan (City 2002). During
Trails shall be maintained on a regular basis, particularly In Construction
the rainy season, to prevent son erosion and sedlmentatlon -& Post
from entering the adjacent wetlands and affecting 'Nater Construction
quallty.
810-7: Waterbars should be Installed on steep tralls to Project-.
prevent accelerated runoff and erosion. Please refer to During
previous Table 1 for the approximate location of these Construction
structures.
BI0-8: Impacts to Jurisdictional wetlands and non-Project-Prior
wetland waters of the U.SJstreambed shall require the to Any
following pennlts by regulatory federal .and state Construction
agencies: 1) ACOE, CWA, Section 404 permit for \
placement of dredged or fill material within waters of the
U.S., 2) RWQCB, DNA, Section 401 state water quality
certification/waiver for an action that may result in
degradation of watera of the State, and 3) CDFG,
California Fish and Game Code, Section 1602
agreement for.alteration of a straambed. The mitigation
for lm~cts to jurisdictional resources must occur In the
fonn of creation or creation • combined with
enhancement; however, the mitigation cannot result In
a net-loss of wetland habitat or wetland functions and
values. "Therefore, a minimum 1 :1 creation ratio must
be applied toward any Jurlsdlctlonal Impacts.
Exvt,,natk>n of l1Mdlo8t;
Type• Project,~. wnu1ettve.
Monltomg Dept. • Department. or Ageooy, 1'811p0nd)le for rnoollorilg a partlcular mitigation rneesura.
800'MI on Plans "When rnltlga1lon ll188IIU"8 Is shoYin on pium, ttilll column llliil be lnllal8d and dated.
(
Monitoring
ueoaru•-··
Parle Planner &
Construction
Contractor
Parle Planner
Construction
Contractor
Planning
Department
V aitfled Implementation " When mlllga1lon ~re haa been lrnplomened, this coh.lnn will be nlllllled and daled.
Remarb • Al8II forcle8o!iJolg eta1ull of ongoing mlgatk,n fTl8alU1l. or for other lnfonna11on. RD -Appendix p.
Shown on Verified Remarks Plans h,~,~,tatlon
Page6of~
810-8: 'The dwelopment of a conceptual mitigation, Project-Ptior
maintenance, and monitoring plan wiU be required for the to Any
wetland mitigation. This plan is a requirement of both the Construction
federal and state wetland permit applications and must be
submitted. with the required pennlt applications. This plan
should Include detaUs regarding grading, Irrigation design,
and planting specifications, as well as maintenance and
monitoring procedures. The plan should also outllne yearly
success criteria and remedial measures should the
mitigation effort taa short of the success criteria. Any
wetland mitigation that cannot be achieved through on-site
restoration and enhancement should be perfonned off-site,
but preferably within the same local watershed; however, off-
site mitigation may require .. higher mitigation ratios.
Alternatively, the mitigation obligations may also be satisfied
by participating In a fee-based mitigation program through a
wetland mitigation bank. The proposed mitigation If? subject
to the resource agencies' review and _discretion; thus, the
mitigation obUgatlons for the Im pads to jw1sdlctional wetland
habitats. may change from what has been recommended
here. Until a conceptual plan ls submitted for permftting,
please refer to the On-site Revegetatlon Recommendations
section of this report for a tentative map of suitable areas for
wetland mltlgatloh as well as approprtate planting material.
810-10: Prior to construction activities,· aU wetland areas Project-Prior
within or adjacent to construction areas should be to Any
encompassed by orange environmental fencing to protect Construction
them from construction as determined appropriate by the
biological monltor and the land Manager. A qualified
biologist shall Inspect all construction fencing prior to
constructlon and shall monitor construction (grading)
activities to avoid W1authorized Impacts.
Expjanation of Hgdhpaj •
Type a Project, ongong, cumulative.
Monltortng Dept. • Depamient, or Agency, reapond>m for monltomg a partloolar ~tlon meaB1.l'8.
Shown on Plans "'When ~tlon -.ire Ill 8hown on pl!,na, 1h18 cokJmn will be lnll!ll9d and dated.
Plannlng
Department
and Biological
Consultant
Construction
Contractor and
Biological
Monitor
Varlfted lmpiementlltlon • When m!llgatlon ITl8ll8Ul'8 hal been Implemented, 1hi! cobnn wU1 be lnlt!aJed end dalBd.
Reinarb C Ama b-descl1b!ng slatlJ8 of oogolng ~ rJ168SUl9, er for other lnfonnatlon, RD -Appendix p. •
Page 8 of 8
HYDROLOGY ~C! WATEB,Q!JAbJTY P reject-Prior Construction
to and Contractor
HYDR0-1: The City shall implement all maintenance During All
operations of pennanent BMPs as outlined In Section 2.5 Construction
[fvtalntenance of Mwilcipal Separate Storm Sewer System Actlvltles
( MS4) of their Jurlscllctlonal Urban Runoff Management Plan
(JURMP)]. The City's Contractor is responsible . for
maintenance of construction BMPs. In particular, slit fencing
or other sediment trapping devices shall be lnstaUed and
maintained In order to prevent runoff from entering the water
svstems durlna-construction activities.
fmboeUoi:t ottlffdfnqa;
Type • Project, ongoing, curoolatlve.
Monllorlng Dept.., Department, or Agency, responslbla for monlkirlng a particular~ ~
Shown' on Plans a Whan mllgaffon measure ls shown on plans, 1hlB cokJmn win be klllalad !Ind datad.
Vedfted ~n = Wt-en mitigation measure haa been inpklmented, thla coomn will ba hlllaled end dalad.
Remarks • Area !or describing 8talLJ8 of ongohg mttlgatlon measure, or for other Woanat!on. RD -Appendbc P.
APPENDIX B
Preliminary Boardw,alk Alignment
(Plan and Photographs)
-APPENDIX C
• Construction Plans for
Lake Calavera Boardwalk Trail and Restoration