Loading...
HomeMy WebLinkAbout3190; Rancho Sante Fe Road Bridge Replacement; Rancho Sante Fe Road Bridge Replacement; 2000-12-01DRAFT CONCEPTLAL WETLAND MITIGATION AND MONITORING PLAN rOR THE RANCnO SANTA EE ROAD REALIGNMENT AND BRIDGE REPLACEMENT PROJECT ] CITY or CARLSBAD, CALIEORNIA mi *' Prepared for: - CITY OF CARLSBAD PUBLIC WORKS - ENGINEERINCi! m m m m m 1635 Faraday Avenue Carlsbad, California 92008 Contact: Douglas Helming TeL (760) 92.9-1600 Prtpartd by: DUDEK & ASSOCIATES, INC. m PmfessioTuiI Teams for Complex Projects m 605 Tfiird Street li Encmitas, Califorma 92024 Sherri L Milltr, Stnior Biologist ohn L Minchin, Landscape Architect # 2225/ m ( / Habitat Restoration Specialist m DECEMBER 2000 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project TABLE OF CONTENTS Section Page m IH m m m m m m m m EXECUTIVE SUMMARY iv 1.0 PROJECT DESCRIPTION AND SITE EVALUATION 1 1.1 Location of Project 2 1.2 Brief Summary of Regulatory Framework 2 1.3 Responsible Parties 5 1.4 Jurisdictional Areas Affected by the Project 5 1.5 Functions and Values of Areas Affected by the Construction Work 7 1.5.1 Water Quahty Issues 7 1.5.2 Rare Or Endangered Species 8 1.5.3 Plant Communities/Habitats 9 1.5.4 Wildhfe 10 1.6 Impacts to Jurisdictional Areas 11 2.0 WETLAND MITIGATION PROGRAM 12 2.1 Goal of Mitigation 12 2.1.1 Types of Habitat to be Created 13 2.1.2 Functions and Values of Habitat to be Created 15 2.1.3 Time Lapse 20 2.1.4 Cost Estimate 20 2.2 Final Success Criteria 21 2.2.1 Existuig Functions and Values of Mitigation Area 21 2.2.2 Target Functions and Values 22 2.2.3 Target Hydrological Regime 22 2.2.4 Target Jurisdictional Acreage to be Created and Enhanced 23 2.3 Proposed Mitigation Areas 23 2.3.1 Location and Size of Mitigation Areas 24 2.3.2 Present and Proposed Uses of Mitigation Area 24 2.4 Implementation Plan 27 2.4.1 Rationale for Expecting Implementation Success 27 2.4.2 Prehminary Schedule 28 il DUDEK & ASSOCIATES, INC. 1576-9 Ptofaaiofui Ttam* for Complex Proffctt December 2000 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project TABLE OF CONTENTS [CONTmUEm Section Page m m m m m m 2.4.3 Site Preparation 29 2.4.4 Final Landscape/Revegetation Plans 30 2.4.5 Temporary Irrigation System 31 2.4.6 As-Built Conditions 32 2.5 Maintenance During Monitoring Period 32 2.5.1 Makitenance Activities 33 2.5.2 General Habitat Maintenance GuideUnes 34 2.5.3 Schedule of Maintenance/Monitorhig Inspections 35 3.0 MONITORING PLAN 35 3.1 Performance Standards 35 3.2 Monitoring Methods 38 3.3 Annual Reports 38 3.4 Schedule for Monitoring 39 3.5 Completion of Mitigation 39 3.5.1 Notification of Completion 39 3.5.2 Regulatory Agency Confirmation 39 3.6 Contingency Measures 40 3.6.1 Procedures for Initiating Contmgency Measures 40 3.6.2 Funding Mechanisms 40 4.0 ACKNOWLEDGMENTS 40 UTERATURE CITED AND REFERENCED 40 m m DUDEK &ASSOCIA'I1ES,INC. 1576-9 Praftuioiwl Teonu jm Complei Projfcti December 2000 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project TABLE OF CONTENTS KCONTMNUEm Page LIST or riGLRCS Figure 1 Regional Map 3 Figure 2 Vicmity Map 4 Figure 3 Jurisdictional Impact Areas 1 & 2 and Onsite Revegetation 6 Figure 4 Biological Resources Map (University Commons Area) 14 Figure 5 Jurisdictional Delineation Map of University Commons Area With Offsite Revegetation Site 16 Figure 6 Conceptual Revegetation Map (Offsite Location) 25 Figure 7 Site Photos 26 LIST or TABLrS Table 1 Acreage Impacts to Jurisdictional Areas for the Proposed Project 12 Table 2 Mitigation Summary for Permanent and Temporary Impacts 13 Table 3 Recommended Container Plants and Seed Mix for Southem Willow Scrub Revegetation 17 Table 4 Recommended Container Plants and Seed Mix for Freshwater Marsh Revegetation 18 Table 5 Recommended Container Plants and Seed Mix for Southern Willow Scrub Enhancement 18 Table 6 Recommended Seed Mix for Restoration of Wetland Habitats 19 Table 7 Recommended Seed Mix for Restoration of Wetland Habitats 18 m m m m m DUDEK & ASSOCIATES, INC. 1576-9 iV(ife»biudiemi)forc<>m/rfe(pr<i^ Decemt)er 2000 fll Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project EXECUTIVE SUMMARY The purpose of this Conceptual Wetland Mitigation and Monitoring Plan is to outline appropriate revegetation measures to mitigate impacts to biological resources that will result from the Rancho Santa Fe Road reaUgnment and bridge replacement (proposed project). The City of Carlsbad proposes to widen and realign Rancho Santa Fe Road from two lanes to an ultimate six lane prime arterial roadway, from approximately 100 feet south of the La Costa Avenue/Rancho Santa Fe Road intersection to approximately 100 feet north of the Melrose Drive/Rancho Santa Fe Road intersection. The proposed project also includes the replacement of the bridge crossing at San Marcos Creek. The project site is located in the approved Fieldstone Habitat Conservation Plan that encompasses 1,940.2 acres of land in southeast Carlsbad. Implementation of the proposed project wiU permanently hnpact a total of 0.69 acre of jurisdictional wetlands, comprised of 0.42 acre of southem wiUow scrub and 0.27 acre of disturbed wetlands. In addition, 0.24 acre of unvegetated, ephemeral waters wiU be permanently impacted. To mitigate for these permanent unpacts, this Conceptual Wetland Mitigation and Monitoring Plan outluies guidelines for the creation of wetland habitats composed of southern wiUow scrub and freshwater marsh. Proposed mitigation for permanent knpacts to southern willow scrub wiU consist of creation of 1.26 acres of southern wiUow scrub. Proposed mitigation for permanent impacts to disturbed wetland habitat wiU consist of the creation of 0.27 acre of freshwater marsh habitat and enhancement of 0.54 acre of freshwater marsh habitat. Proposed ^ mitigation for permanent impacts to unvegetated ephemeral waters of the U.S. wiU consist of the ^ creation of 0.24 acres of freshwater marsh habitat. * The proposed mitigation site for permanent impacts resulting from the Rancho Santa Fe Road Realignment and Bridge Replacement Project wiU be located offsite withki the University ^ Commons project along San Marcos Creek. The proposed offsite mitigation area is located g| immediately east of Rancho Santa Fe Road along the margins of San Marcos. m m m m Temporary wetland impacts associated with the Rancho Santa Fe Road ReaUgnment and Bridge Replacement Project construction will include 0.97 acre of southern v^iUow scrub. Proposed mitigation for temporary impacts to southem wiUow scrub consist of onsite restoration of 0.54 acre of southern wiUow scrub within the areas of temporary knpact. Because of bridge shading effects, creation of 0.43 acre of southern wiUow scrub and enhancement of 0.86 acre of southern wiUow scrub wiU occur at the proposed offsite mitigation area. DUDEK & ASSOCIATES, INC. 1576-9 i^itftui<maiTeam>jbrCc«4ri«fW<ct> December 2000 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project m A total of 4.14 acres of wetland habitat creation, enhancement and restoration wiU be provided kl order to compensate for total knpacts of 1.90 acres (i.t., permanent knpacts to 0.69 acre of wetlands and 0.24 acre of unvegetated, ephemeral waters and for temporary impacts to 0.97 acre of wetlands). Hi ill This Conceptual Wetland Mitigation and Monitormg Plan has been prepared in accordance with the guidelines recommended by the U.S. Army Corps of Engkieers (ACOE) for mitigation plan preparation. This plan presents information on project location and work descriptions, permitting requirements, project impacts, mitigation requirements, planting and irrigation recommendations, maintenance requkements, monitorkig methodology and final revegetation success criteria. m m m m m m DUDEK &ASSCX:iATES, INC. 1576-9 IV<>fwlon<dT«nuf<>rCon>t>laPr<>M' DeCembSr 2000 m m m k k m m Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 1.0 PROJECT DESCRIPTION AND SITE EVALUATION The City of Carlsbad (the AppUcant) proposes to widen and reaUgn Rancho Santa Fe Road from two lanes to an ultknate six lane prkne arterial roadway ki the eastem portion of the City of Carlsbad and western portion of San Marcos, CaUfornia. The proposed project wiU widen and reaUgn Rancho Santa Re Road from approximately 100 feet south of the La Costa Avenue/Rancho Santa Fe Road intersection to approxknately 100 feet north of the Melrose Drive/Rancho Santa Fe Road kitersection. The proposed project also kicludes the replacement and relocation of the San Marcos Creek bridge crossing. In accordance with the City of Carlsbad's General Plan and the 1992 Envkonmental Impact Report (EIR), Rancho Santa Fe Road wUl be upgraded to a Prime Arterial Roadway which wiU include a 126-foot right-of-way contakiing six travel lanes, bike lanes, an 18-foot wide raised median, sidewalks, curb and gutter. The proposed project is divided into Phases 1 and 2. Phase 1 includes the realignment of approxknately 7,000 feet of Rancho Santa Fe Road from La Costa Avenue to the bridge and the removal of the existmg Ranch Santa Fe Road. Phase 2 consists of the proposed bridge replacement as weU as the reaUgrmient of the 2,200 feet approach from Melrose Drive to approximately 600 feet south of the Questhaven/Rancho Santa Fe Road intersection. The project site is located ki the approved City of Carlsbad's Fieldstone/La Costa Associates Habitat Conservation Plan (HCP) that encompasses 1,940.2 acres of land in southeast Carlsbad. Implementation of the proposed project wiU permanently impact 0.42 acre of southem willow scrub, 0.27 acre of disturbed wetlands and 0.24 acre of unvegetated ephemeral waters of the U.S. Temporary impacts include 0.97 acre of southem wiUow scrub. These habitat types are considered jurisdictional wetlands and waters. The proposed mitigation program will include a total of 2.2 acres of offsite creation and 1.40 acres of offsite enhancement of jurisdictional southern willow scrub and freshwater marsh habitats. The proposed mitigation area is located immediately east of the project corridor within University Commons along San Marcos Creek {Figurts 4 and 5). The mitigation area will be preserved as an element of the Fieldstone HCP. In addition, 0.54 acre of jurisdictional southern wiUow scrub habitat wiU be restored onsite within the area of impact along San Marcos Creek. In order to determine the appropriate mitigation measures for the project, the pre-existkig conditions of the proj ect site were assessed through a plant community/habitat survey, a wetland DUDEK & ASSOCIATES, INC. 1576-9 p™;i™i™iT«<iwji>r Comple. PMi«ci» December 2000 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project deUneation and general wildlife surveys conducted from 1990 to 2000 by biologists from Dudek & Associates, Inc. (DUDEK), HeUx Envkonmental (HELIX) and Sweetwater Envkonmental (SEB). AdditionaUy, site evaluations to determkie mitigation/revegetation potential at the proposed onsite mitigation areas as weU as within the University Commons project were conducted by Myloc Nguyen (Biologist/Habitat Restoration SpeciaUst) and John L. Mkichki (Landscape Architect#2225/Habitat Restoration SpeciaUst) in September and October 2000. The site visits mcluded mapping of potential creation and enhancement areas. 1.1 Location of Project The proposed project site occupies 138 acres in the eastern portion of the City of Carisbad and western portion of the City of San Marcos, CaUfornia, approxknately one mile southwest of Lake San Marcos {Figurt 1). Rancho Santa Fe Road defines the jurisdictional boundary between Carlsbad and San Marcos. Residential developments are located west of the existing Rancho Santa Fe Road in the southern portion of the project site and north of San Marcos Creek. An kidustrial park is situated northeast of Rancho Santa Fe Road and Questhaven Road. Vacant lands occupy areas west of existing Rancho Santa Fe Road ki association with San Marcos Creek and areas on the east side of existkig Rancho Santa Fe Road between La Costa Avenue and Questhaven Road. The project footprkit lies within the northwestern portion of the Rancho Santa Fe, CaUfornia, U.S. Geological Survey 7.5 minute quadrangle; Sections 1,6,19,20,29,30, 31 and 32; Townships 12 and 13 South; Range 3 and 4 West; longitude 117°13' 29" and latitude 33°05'42" {Figurt 2). The project site is located in the City of Carlsbad's Fieldstone/La Costa Associates HCP. 1.2 Brief Summary of Regulatory Framework This mitigation plan addresses biological knpacts that are regulated by the Federal Clean Water Act and the California Fish and Game Code; and administered by the U.S. Army Corps of Engmeers (ACOE), Califomia Department of Fish and Game (CDFG) and the Regional Water QuaUty Control Board (RWQCB). This plan outlmes mitigation and revegetation strategies that wiU fulfiU the regulatory requirements ofthe Federal Clean Water Act and CaUfornia Department of Fish and Game Code and wiU support applications for issuance of ACOE 404 Nationwide g| permks 14,18,33 and a CDFG 1601 Streambed Alteration Agreement. This plan is designed to comply with regulatory requirements to achieve ''No Net Loss of Wetlands." m m k m m DUDEK & ASSOCIATES, INC. 1576-9 Pn/iesiioiul Teonu for Complei Projcctj December 20OO Orange County San Orego r-SMiles Tijuana MBXICO m m m m Conceptual Wetland Mitigation and Monitoring Plan • Rancho Santa Fe Road Regional Map FIGURE ' l?U' J Offsite Ranctro Santa Fe Road Revegetation Site (See Figure 6) University Commons Revegetation Sites -^--w i:-;-^rm BASE MAP SOURCE: USGS 7.5 Minute Series, Rancho Santa Fe Quadrangle l"-2000' Conceptual Wetland Mitigation and Monitoring Plan - Rancho Santa Fe Road Vicinity Map FIGURE Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project to 1.3 Responsible Parties This Conceptual Wetland Mitigation and Morutormg Plan is submitted on behalf of the City of Carlsbad (the Applicant). The representatives for the Applicant are Mr. Douglas Helmmg and Ms. Carrie Loya. The Applicant wiU be fimanciaUy responsible for aU negotiations and costs *• associated with the implementation, monitoring, maintenance and protection of the mitigation site defined ki this document. m Proposed wetland mitigation/revegetation areas withki the project area shaU be accessible to the * ACQE and CDFG throughout the project review and permittkig phase, as weU as during the instaUation and five-year monitoring period. m ^ This plan was prepared by DUDEK staff serving as envkonmental consultants to the City of Carlsbad. The representatives at DUDEK are Sherri L. Miller (Biologist), John L. Minchin ^ (Landscape Architect#2225/Habitat Restoration SpeciaUst), and Myloc Nguyen (Biologist/ Habitat Restoration Specialist). m ^ 1.4 Jurisdictional Areas Affected by the Project m m A delkieation of "waters of the United States" and wetlands under the jurisdiction of the ACOE was conducted for the project area between 1997 and 2000 by SEB, HELIX and DUDEK ^ biologists. The ACOE jurisdictional wetland delineation was conducted ki accordance with the ^ 1987 U.S. Army Corps ofEnginters WttlandDtlintationManual (TR Y-87-1); hydrology, vegetation, and soils were examined at potential wetland sites. MunseU Soil Color Charts were used to * determine soil chroma and value and the kidicator status of the plant species was determined by * using the U.5. Fish and Wildlift Service National List of Plant Species that Occur in Wetlands: ^ California (Region 0). The extent of wetland features was determined in the field by stakkig, g| surveykig, and using Global Positionkig System (GPS) equipment; these shapes were transferred to the topographic base, and digitized into an ArcCAD file {Figure 3). m The proposed project would include permanent impacts to 0.42 acre of southern willow scrub, ^ 0.27 acre of disturbed wetlands and 0.24 acre of unvegetated ephemeral waters of the U.S. within li the proj ect site. Permanent knpacts to southern willow scrub and unvegetated ephemeral waters of the U.S. would occur as a result of the fillkig and dredgmg for construction of abutments, * bridge piers and a storm draki outfall stmcture associated with the repiacement of the bridge over m k 1576-9 i^eukmai-aomtfmcomtitxPni,cu December 2000 5 li Conceptual Wetland Mitigation and Monitoring Plan - Rancho Santa Fe Road Jurisdictional Impact Areas 1 and 2 and Onsite Revegetation FIGURE Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project San Marcos Creek. Permanent knpacts to disturbed wetlands and unvegetated ephemeral waters of the U.S. would be incurred as a result of the fiUkig and gradkig for construction of the roadway and associated slopes (Figure 3). Temporary knpacts to southern wiUow scrub, totalkig 0.97 acre, would occur as a result of the demolition of the old bridge and replacement of the bridge over San Marcos Creek (Figure 3). 1.5 Functions and Values of Areas Affected by tfie Construction Worl( m m k m •I k 1.5.1 Water Quality Issues Water quality withki San Marcos Creek could be affected by the realignment and widening of Rancho Santa Fe Road, the bridge replacement over San Marcos Creek and proposed revegetation program. Measures to avoid or mitigate knpacts to water quaUty have been mcorporated kito the project design and include the foUowing: • Construction Phase: During the construction phase, Best Management Practices (BMPs) wiU be applied to control stormwater runoff and to provide sedknent and dust controL These measures include: Gravel berm, filter fabric fences, Unes of straw bales, to prevent erosion; Surfacing of roadways wiU occur as soon as possible; Project design wiU ensure that no additional runoff durkig constmction will drain kito San Marcos Creek; AU trash, debris, and refuse generated during gradkig will be contained and removed; Periodic watering of areas to rxiinimize dust; - - Prompt revegetation of surrounding areas to prevent erosion; When feasible, hauling by the developer wiU be accompUshed in a marmer that mkiimizes the spiUage of soU onto roads ki developed areas; Trash, debris and refuse material such as oil, grease, broken equipment and construction trash generated during grading wiU be properly contained and removed offsite to a disposal site; The Bridge Replacement Final AUgnment Plans wiU adhere to recommendations made by Dokken Engkieerkig in thek 2000 report entitled Structural Calculations for Rancho Santa Fe Road Bridge Over San Marcos Creek regarding bridge construction; m DUDEK & ASSOCIATES, INC. 1576-9 Prafuiaul Teonu for Comjilcx Profccti December 2000 m k m m k m k m Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project The Contractor wiU prepare and submit to the RWQCB a Stormwater PoUution Prevention Plan (SWPPP) in accordance with the requirements of a constmction activity permit; and - - To minimize water quaUty degradation by sedimentation of the creek charmel during constmction, construction of the new piers and demolition of existing piers will be limited to the dry season (March to October). • Operational Phase: The roadway design mcludes devices for storm water treatment. These devices capture and treat the storm water prior to discharge to the creek. BMP's wiU also be applied to reduce pollutant loads to the creek. These BMP's wiU include use of rip-rap at storm drain outlets to reduce the velocity of runoff. - - The City wiU follow aU recommendations made pertakikig to erosion control m the geotechnical evaluation by Geocon, Inc., the Cityof Carlsbad's Gradkig, Clearmg and Gmbbing PoUcy, Gradkig Ordmance, and the City's Landscape Manual. 1.5.2 Rare Or Endangered Species No state- or federaUy- Usted rare, threatened or endangered species were observed onsite. Three species recognized as locally sensitive (i.e., narrow endemic) by the California Native Plant Society (Skinner and PavUk 1994) were detected and mapped onsite: southwestern spkiy rush (Juncus acutus var. leopoldii), California adolphia {Adolphia californica) and San Diego golden-star {Muilla clevelandii). A small population of southwestern spiny rush was observed withki San Marcos Creek and could be affected by the instaUation of a temporary access road and construction of bridge abutments (Figure 3). An undetermkied number of California adolphia and approximately 1,500 kidividuals of San Diego golden-stars would be permanently impacted by the proposed project. One wildlife species, California gnatcatcher (Polioptila californica) recognized as threatened by the USFWS was not detected but could potentiaUy occur within the coastal sage scrub onsite. In addition, the foUowing species recogrkzed as USFWS "sensitive species" and/or as "species of mi special concern" by CDFG either occur or could potentiaUy occur witfm the proj ect area: Cooper's H hawk (Accipiter cooperii), loggerhead shrike (Lanius ludovicianus), BeU's sage sparrow (Amphispiza belli belli), southern CaUfomia mfous-crowned sparrow {Aimophila ruficeps canescens), two-striped * gartersnake (Thamnophis hammondii), San Diego homed lizard {Phrynosoma coronatum blainvillei), & ASSOCIATES, INC. 1576-9 Pn/iuiiDitol T^nsiu ftyr Conpia Projecti December 2000 m m m k m k m k m k Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project western spade-foot toad (Scaphiopus hammondii), coastal western whiptail (Cnemidophorus tigris multiscutatus), red-diamond rattlesnake (Crotalus exsul), coastal rosy boa (Lichanura trivirgata roseofusca), Dulzura California pocket mouse (Chaetodipuscalifornicus femoralis), northwestern San Diego pocket mouse (Chaetodipus fallax fallax), San Diego desert woodrat (Neotoma lepida intermedia) and San Diego black-tailed jackrabbit (Lepus californicus bennettii). Mitigation for potential impacts to the species discussed above is addressed within the Biological Resources Technical Rtport d2 Impact Analysis for the Rancho Santa Fe Road Realignment and Bridge Projtct, prepared by DUDEK and dated April 2000. 1.5.3 Plant Communities/ Habitats The wetlands within the proposed impact areas consist of southem wUlow scmb and disturbed wetlands. Impacted habitats are shown ki Figurt 3. Descriptions of these plant communities/ habitats are provided below. ACOE and CDFG ]urisdictiona! Areas Southem Willow Scmb (0.42 acre permanent unpact and 0.97 acre temporary impact) HoUand (1986) describes southern wiUow scmb as "dense, broad-leafed, winter-deciduous riparian m thickets dominated by several species of wiUows (Salix sp.), with scattered emergent Fremont ig cottonwood (Populus frtmontH) and western sycamore (Platanus racemosa)" The understory is usuaUy depauperate owing to the dense canopy. m * The southern wiUow scrub habitat in San Marcos Creek was not bumed during the 1996 fke and supports arroyo wiUow (Salix lasiolepis), western sycamore, Fremont cottonwood, rush (Juncus ii spp.), wmged tfiree-square {Scirpus americanus), Mexican elderberry (Sambucus mexicanus), and cattails (Typha sp.). Understory species ki the southem wiUow scrub habitat kiclude Califomia mugwort {Artemisia douglasiana), curly dock (Rumtx crispus), yerba mansa {Antmopsis californica), rigid hege-nettle (Stachys ajugoidts var. rigida), Mexican tea {Chenopodium ambrosioidts), and poison-oak (Toxicodendron divtrsilobum). A total of 1.72 acres of southem wiUow scmb habitat was M mapped by DUDEK {Figure 3). k 1576-9 pT<,f™io»dTBmu/orc«nfj«p«.j««i Deccmber 2000 9 m m m m m Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project Disturbed Wetlands (0.27 acre permanent impact) In general, the disturbed wetlands designation is used ki areas where hydrophytic vegetation, significant hydrology and hydric soils are present and the plant community appears to be disturbed. Disturbed wetlands are usuaUy dominated by herbaceous species such as English ryegrass (Lolium multiflorum), rushes, curly dock and armual rabbit's foot grass (Polypogon monspeliensis). Within the proj ect area, disturbed wetlands occur in a shaUow drainage surrounded by bumed and disturbed coastal sage scrub with some adjacent grasslands. Dominant species withki the disturbed wetlands consist of EngUsh ryegrass, mshes, and curly dock. Disturbed wetlands occupy 0.27 acre (Figure 3). Unvegetated Effhemeral Waters ofthe U.S. (0.24 acre permanent impact) A total of 0.24 acre (3,890 Ikiear feet) of unvegetated ephemeral waters of the U.S. wiU be permanently knpacted as a result of fiUing and gradkig activities between Questhaven Road and La Costa Meadows Road. 1.5.4 Wildlife WUdlife habitats present within the project area include riparian/wetland habitats and upland habitats (Figure 3). WUdUfe habitats of greatest value are those that are (1) rare In San Diego County, (2) highly productive, or (3) capable of supportmg sensitive species. The vegetational/habitat diversity of the site, the large amount of "edge" habitat which provides openings for wUdlife to forage ki and the existing wetland resources which provide water for both upland and wetland wildlife species are expected to support a relatively rich native fauna. A complete Ust of wUdlife species observed is attached as Appendix B of the Biological Resources Technical Report cS^ Impact Analysis for the Rancho Santa Fe Road Realignment and Bridge Project. The list includes wUdlife species which were detected before the Qctober 1996 fire but may no longer be present due to the ioss of habitat and refuge resulting from the fke. DUDEK & ASSOCIATES, INC. 1576-9 ProfWulimd Tuna for CampUxProitca December 2000 10 k m m k m k m m Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project A total of 84 species of bkds was observed during the wUdUfe surveys. The avifauna is comprised of a moderately diverse assemblage of species associated with coastal sage scmb, along with several species found more commonly in riparian habitats and grasslands. Habitats onsite kicluding coastal sage scrub, southern mixed chaparral, armual grassland and riparian provide habitat for a variety of bkds including the California towhee (Pipilo crissalis), spotted towhee (P. erythrophthalmus), CaUfornia thrasher (Toxostoma redivivum), mourning dove {Zenaida macroura), bushtit (Psahriparus minimus), wrentit (Chamaea fasciata), house finch (Carpodacus mexicanus), black phoebe (Sayornis nigricans), and European starling (Sturnus vulgaris). Red-taUed hawk (Buteo jamaicensis) and Cooper's hawk were observed foragmg m the riparian area. A total of nkie species of reptUes was observed onsite. Common reptUe species occuring ki the area mclude southern aUigator lizard (Gerrhonotus multicarinatus), side-blotched Uzard (JJta stansburiana), western fence lizard (Sceloporus occidentalis), whiptaUs (Cnemidophorus spp.), gopher snake (Pituophis mtlanoleucus) and rattlesnakes (Crotalus spp.). A total of three amphibian species was observed ki the riparian area: CaUfornia treefrog (Hyla cadaverina). Pacific treefrog (Pseudacris hyla regilla)and buUfrog (Rana catesbeiana). A total of fourteen species of mammals was observed onsite. Common mammal species occuring m the area kiclude rabbits (Sylvilagus spp.), striped skunk (Mephitis mephitis), deer mouse (Peromyscus maniculatus), Dulzura Califorrua pocket mouse (Chaetodipus californicus femoralis), mule deer (Odocoileus hemionus), coyote (Canis latrans), gray fox (Urocyon cinereoargenttus), and Pacific kangaroo rat (Dipodomyus agilis), woodrats (Neotoma spp.) and harvest mouse {Reithrodontomuys mtgalotis). A total of 24 invertebrates was observed onsite. Common invertebrate species occurring in the area include funereal duskywing (Erynnis funtralis), westem checkered skipper (Pyrgus albens), swaUowtaUs (Papilio spp.), Behr's metaUnark (Apodemia mormo virguiti), West coast lady (Vannessa annabella), painted lady (V. cardui) and common white {Pontia protodice). ^ 1.6 Impacts to Jurisdictional Areas m DUDEK has determkied, uskig ArcCAD to overlay the proposed project footprint over the jurisdictional areas, that a total of 0.93 acre of southem wiUow scmb, disturbed wetlands and unvegetated waters of the U.S. under the jurisdiction of ACOE and CDFG wiU be permanently impacted by the implementation of the proposed project. In addition, 0.97 acre of southem wiUow scrub under the jurisdiction of ACOE and CDFG wUl be temporarUy impacted. See Table DUDEK & ASSOCIATES, INC. 1576-9 p™feuioi«iTeam./Drc*™iJniv,K« Decembcr 2000 11 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project i for a summary of aU impacts to jurisdictional areas associated with the implementation of the proposed project and the resultant preserved wetland acreages. TABLE 1. ACREAGE IMPACTS TO JURISDICTIONAL AREAS FOR THE PROPOSED PROJECT (Rancho Santa Fe Road Impact Area) k m k Pemiamiit Impacts Temporary Impacts Remaining Acreages Habitat Type Existing Acres (Acres) (Acres) after Impacts Southem willow scrub 1.72 0.42 0.97 0.33 Distuited wetlands 0.27 0.27 0 0 Unvegetated waters 0.45 0.24 0.21 0 TOTAL 2.44 0.93 1.18 0.33 2.0 WETLAND l\/IITIGATION PROGRAM k m m k 2.1 Goal of Mitigation The maki goal of the wetland mitigation program is to mitigate for the permanent and temporary impacts to wetland habitats within San Marcos Creek through offsite and onsite revegetation efforts. Mitigation for permanent impacts to southem wiUow scrub and disturbed wetland composed of freshwater marsh consists of offsite creation, at a ratio of 3:1, of 1.26 acres of southem wUlow scrub; offsite creation, at ratio of 1:1, of 0.27 acre of freshwater marsh; and offsite enhancement, at a ratio of 2:1, of 0.54 acre of freshwater marsh habitat. Mitigation for permanent impacts to unvegetated ephemeral waters of the U. S. consists of offsite creation, at a ratio of 1:1, of 0.24 acre of freshwater marsh. Additional proposed mitigation for temporary impacts to southern wUlow scmb consists of onsite restoration, at a ratio of 1:1, of 0.54 acre of southem wUlow scrub. The balance (0.43 acre) of the southern wiUow scrub habitat at the temporarUy knpacted stream charmel wUl be mitigated offsite through creation, at a ratio of 1:1, of 0.43 acre of southern wiUow scrub and enhancement, at a ratio of 2:1, of 0.86 acre of southern wiUow scrub. In total, 3.09 acres of southem wUlow scrub and 1.05 acres of freshwater marsh creation, enhancement and restoration wUl be provided. Mitigation acreage to be provided wiU thus total approximately 4.14 acres of wetland habitat credit. Table 2 shows the summarized permanent and temporary impact quantities for the proposed project as weU as nutigation ratios and k DUDEK & ASSOCIATES, INC. 1576-9 PnfeaumitnimiaitrrCtmtiaPToiB^ December 2000 12 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project nutigation requkements. Figure 6 iUustrates the prelkninary revegetation scheme for the proposed mitigation site. TABLE 2 MITIGATION SUMMARY FOR PERMANENT AND TEMPORARY IMPACTS k Required Mitigation m Required Mitigatiim Ratio (Acres) Total Proposed m Impacts * Onsite Mitigation Habitat Type (Acrsi) Creation Enhancement Restoration Creation Enhancement Restoration (Acres) m Permanent Impacts* m Southern willow scrub 0.42 3:1 --1.28 - -1.26 m Disturbed wetlands 0.27 1:1 2:1 -0.27 0.54 -0.71'** m Waters of the U.S. 0.24 1:1 --D.24 --0.24*** Temporary Impacts*" m Southem Willow 0.97 m Scrub onsite nutigation 0.54 - -1:1 - -0.54 0.54 m offsite mitigation 0.43 1:1 2:1 -0.43 0.86 -1.29 k Totals bvundad) U 1 2.2 tj40 0.54 4.14 • Permanent impacts resulting from the Rancho Santa Fe filling and grading. • • Temporaiy impacts being compensated for through onsite restoration of temporary disturbance locations following completion of construction and additional creation/enhancement acreage at the offsite locatioiL **• Mitigation aaeage for impact to disturbed wetlands and waters of the U.S. will be compensated for with freshwater marsh creation and enhancement offsite. m m m m k m m k 2.1.1 Types of Habitat to be Created The mitigation program proposes to provide revegetation of 4.14 acres of wetland habitats through creation, enhancement and restoration of southern wiUow scmb and freshwater marsh, both onsite and offsite. The proposed revegetation program wiU include 2.2 acres of creation, 1.40 acres of enhancement, and 0.54 acre of restoration of southem wUlow scrub and freshwater marsh habitats. The creation and enhancement of southern wUlow scmb and freshwater marsh habitats wUl occur offsite, while the restoration of temporarUy disturbed southem wUlow scmb habitat wiU occur onsite (Figure 3). The proposed areas of wetland habitat creation wiU occur withki non- native upland habitats adjacent to riparian vegetation which wUl be excavated to proper elevations to support the kitended habitats (Figure 4). The southern wUlow scmb and freshwater marsh enhancement areas wUl occur withki patches of existkig southern wUiow scrub habitat and DUDEK & ASSOCIATES, INC. 1576-9 Profaiimud Teams for ComptaPr^ieU December 2000 13 ftl ftl WiM 1k..M ftl ftl ri II ftl ftl 11 11 Kl 11 1 ftl i I 11 i I ..: l-^^li'^'-'il' ' \ j^lfiA\^A'i:!iy--"-- •'^v^ Ownership Boundaiy TMl = Brookfield/Brouwer TM2 = CIC TM3 = Shelley BASE TOPO SOURCE: O'DAY CONSULTANTS Sc^a in Feet Conceptual Wetland Mitigation and Monitoring Plan - Rancho Santa Fe Road Biological Resources Map • University Commons Area FIGURE Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project freshwater marsh habitat that contain an abundance of exotic/weedy species such as eucalyptus (Eucalyptus sp.) trees, pampas grass (Cortaderia selloana), ^ant reed (Arundodonax) and other weed species (Figure 5). Also, the proposed enhancement areas wiU be located adjacent to the southern wUlow scrub creation area, as weU as existmg freshwater marsh patches; therefore, the enhancement program wiU help decrease exotic/weed invasion within the newly created wetland habitat as weU as within the existing wetland habitat. The proposed restoration of 0.54 acre of southern wiUow scrub habitat wUl occur onsite witiun the area of temporary impact resulting from bridge constmction. The mitigation/revegetation plant palettes have been designed to include a composition of species simUar to existing and adjacent natural areas. Tables 3 through 6 show the intended species compositions, the anticipated spacings on center, the size for kiitial plantings from container stock, and the intended plant species from seed for creation, enhancement and restoration of southern wUlow scrub and freshwater marsh habitats within the mitigation areas. The created, enhanced and restored wetland habitats ultimately are expected to have higher functions and vadues than the existing habitats to be impacted, through the expansion of the riparian corridor, the enhancement of degraded wetlands, and the replacement of existing non- native habitat with native habitat. The mtent of the revegetation program is to encourage the natural restoration process as weU as to create and enhance wetland habitat by removing non- native exotic species. This wUl help estabUsh appropriate native plant assemblages which wUl further develop over time kito the intended plant communities. 2.1.2 Functions and Values of Habitat to be Created The created, enhanced and restored wetland areas are ultknately expected to expand upon the existing riparian habitat and become a functioning part of the riparian system. The intended revegetation program wUl encourage the natural restoration process by helping to remove and control non-native exotic weed species and wUl support the development of appropriate native plant habkats. The proposed revegetation areas are located immediately adj acent to existkig riparian vegetation or are ki upland areas which can be marupulated through excavation to create appropriate wetland conditions. In addition, degraded wetland areas would be improved and enhanced through removal of exotics and revegetation. Thus, through site grading to lower elevations for k better water table relationships, appropriate ecological conditions wUl be created to help support m m k m k & ASSOCIATES, BMC. 1576-9 pn^iorndTtaaufoTCon^PTojea, Decembef 2000 15 i ftl ftl ftl ftl ftl f 1 II II II II II II II lllllllll w f " C HW^ Herbaceous Wetland OC ^ Open Channel KQW| Open Water / Ownership Boundaiy TMl = Brookfield/Brouwer TM2 = ac TM3 = Shelley BASE TOPO SOURCE: O'DAV CONSULTANTS Offsite Rancho Santa Fe Rd. Mitigation Area (See figure 6) Scale kl Feet Conceptual Wetland Mitigation and Monitoring Plan • Rancho Santa Fe Road Jurisdictional Delineation Map - University Commons Area (with Offsite Revegetation Site) FIGURE 5 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project TABLE 3. RECOMMENDED CONTAINER PLANTS AND SEED MDC FOR SOUTHERN WILLOW SCRUB REVEGETATION (1.69 acres offsite creation) (Assumes 100% cover) Spacing on Approx. mm BotanicallComnwn Name Container Size Convosition Center Quantitv m Trees (overstonrKassumes 100% overstary cover) Plataim raceimsa - western svcamore Igai. 10% 25 ft. 12 mm SaSxIask)!^ - arroyo wAw** IgaL 50% 12 ft. 256 m S^gooddm^ - black wiHow** IgaL 30% 15 ft. 98 SanAucus mexicanus - Mexican elderberry Igai-10% 12ft. 51 SiAtotat 417 m Shrubs (understoryXassunes 100% understory cover) Iftft Artemisia painefi - San Diego sagewort Igai. 10% 3 ft. 818 Baccharis saScifoia - mule fat Igai. 30% 6 ft. 613 m fvahayesma - San Diego marsh elder Igai. 10% 4 ft. 460 *tm Jmctis acutus - s|wiy rush Igai. 10% Sft. 115 Pkic/t^ odorata - salt marsh fleabane IgaL 15% 8ft. 173 m Rosa caSforma - CaSfomia wid rose IgaL 15% 6 ft. 307 Rubus arsmus - Ci\\forma blackberry IgaL 10% Sft. 294 SiAtotat Z780 *• Total 3,197 Hydroseed Mix "%P/%G Us/Ac. m Ambmsia p^ostachya • westem ragweed 2/30 2 Artemisia douglamia • mugwort 10/50 6 mm Artemisia pabmi • San Oiego sagewort 15/50 4 m Isocoma menmsi • coast goUenbush 98/75 2 Iva hayesiana - San Diego marsh elder 35/20 6 0m Lotus atf^arm • deerweed 90/60 4 m li^ms iKcohr • pygmy-lsaved lupine 98/80 2 f^hea odorata • marsh fleabane 35/60 4 Total Lbs. Per Acre 30 lbs. %P/%G • Minimum percentage purity and percentage gennmation for acceptable seed quafity. Local collection of propagules from tha San Oiego County region will be required as the source for these species. DUDEK .& ASSOCIATES, INC. I = p»fcuii»aiT<am)/»rCa>i<f>UiProj*ct> Decomber 2000 1576-9 17 Conceptual Wedand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project m k TABLE 4. RECOMMENDED CONTAINER PLANTS AND SEED MIX FOR FRESHWATER MARSH REVEGETATION (0.51 acre offsite creation) (Assumes 100% cover) m Container Spacing Approx. Botanical/Common Name Size Composition on Center Quantity mm Ammof^is californica - Yerba mansa Igal. 10% 2 ft. 555 m Eleocharis macrostachya - pale spike-sedge 6" pot 10% 1ft. 2,222 m Juncus acutus - southwestem spiny rush Igal. 10% 4 ft. 139 Juncus hufonius - toad rush 6" pot 10% 1ft. 2,222 m Scirf^us americanus- Olney's bulrush Igal. 30% 2 ft. 1,666 m Scirf?us californicus - Califomia bulmsh Igal. 30% 3 ft. 741 m Total 7,545 m TABLE 5. RECOMMENDED CONTAINER PLANTS AND SEED MIX FOR SOUTHERN WILLOW SCRUB ENHANCEMENT mm (0.86 acre of offsite enhancement) Container Spacing Approx. Botanical/Common Name Size Composition on Center Quantitv mm Trees (overstoiy) (assumes 70% overstory cover due to existing vegetation to be present) Platanus racemosa - westem sycamore Igal. 5% 25 ft. 3 Salix lasiolepis - arroyo willow*' Igal-40% 12 ft. 104 Salix gooddingii - black willow* * Igal. 20% 15 ft. 33 Ml Sambucus mexicanus - Mexican elderberry Igal. 5% 12 ft. 13 Suhtotat Shrubs (understory) (assumes 50% understory cover) m Baccharis salicifolia ~ mule fat Igal. 30% 12 ft. 78 Iva hayesiana - San Diego marsh elder Igal. 10% Sft. 59 m Juncus acutus - spiny msh Igal. 10% 16 ft. 15 m Suirtotat iSZ Total 305 m Hydroseed Mix (for ail bare areas) *%P/%G Lbs/Ac. Itf Ambrosia psilostachya - westem ragweed 2/30 2 m Artemisia douglasiana - mugwort 10/50 6 Anemisia palmeri - San Diego sagewort 15/50 4 Isocoma menziesii - coast goldenbush 98/75 2 Iva hayesiana - San Diego marsh elder 35/20 6 il Lotus scoparius - deerweed 90/60 4 Lupinus bicolor - pygmy-leaved lupine 98/80 2 m Pluchea odorata - marsh fleabane 35/60 4 Total Lbs. Per Acre 30 Ibs. %P/%G - Minimum percentage purity and percentage germination for acceptable seed quality. * Local collection of propagules from the San Diego County region wiU be required as the source for these species. DUDEK & ASSOCIATES, INC. 1576-9 ProfadimonimnfmCoatlaPnitcU DeCembOr 2000 18 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project TABLE 6 RECOMMENDED SEED MJX FOR RESTORATION OF WETLAND HABITATS (0.54 acre of onsite restoration) m Hydroseed Mbc (Apply to all bare/disturbed areas) *%P/%G Lbs/Ac. Ambrosia psilostachya - westem ragweed 2/30 2 Anemisia douglasiana - mugwort 10/50 6 m Artemisia palmeri - San Diego sagewort 15/50 4 Isocoma menziesii - coast goldenbush 98/75 2 m Iva hayesiana - San Diego marsh elder 35/20 6 m Lotus scoparius - deerweed 90/60 4 Lupinus bicolor - pygmy-leaved lupine 98/80 2 m Pluchea odorata - marsh fleabane 35/60 4 m Total Lbs. Per Acre 30 lbs. Hi the establishment of the intended wetland species and expansion of the riparian zone. The southem wiUow scrub and freshwater marsh revegetation areas are expected to be fairly well- developed by the end of the five-year maintenance and monitoring period due to their extremely fast growth rate. Throughout the project, conversion of degraded uplands to wetlands^ removal of exotics/weeds from existing wetlands^ expansion of wetland resources and genetic continuity of plant materials through the revegetation effort wUl be unportant goals of the overaU mitigation program and should lead to improved functions and values for the overaU riparian system. Additional container plantings and seed appUcations of appropriate native understory shrub and herbaceous species wiU help stabUize the surface soUs and wUl help improve long-term habitat diversity through understory plant development. Mitigation for unpacts to wetlands wiU include replanting with native plant associations utiUzing appropriate native species for the intended plant communities. The mitigation habitats have been designed to provide a mixture of tree, shrub and herbaceous groundcover species to achieve both overstory and understory compositions simUar to adjacent undisturbed natural areas. k DUDEK & ASSOCIATES, INC. 1576-9 Profculonal Teonu fm Comfil*!! Prajed) December 2000 19 m m m m m m Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project The revegetation effort wUl coimect and expand existmg patches of native habitat and wUl enhance v^dldUfe habitat use along the riparian corridor by providmg increased plant cover and protection. An added benefit of the revegetation program wiU be the eradication of non- native/exotic plant species and weeds from the native habitats to be preserved. The eradication program wiU be implemented during the revegetation site preparation procedures and wiU continue durmg the long-term mamtenance period. 2.1.3 Time l^pse It is Ukely that the southern wUlow scrub creation and enhancement areas require 10 to 15 years or longer to approach the general structure, height, and canopy cover of a mature riparian habitat. However, within five years the Uitended native plant material compositions should be established enough to survive under natural conditions and to have adequate coverage to help minimize uivasion of exotic species. By the end of the five-year maintenance and monitoruig period, it should be apparent whether the revegetation efforts have been successful and have lead to a self-sustaUmg habitat. The freshwater marsh creation and enhancement areas should be weU-established by the end of the third year of the monitoring program. m m 2.1.4 Cost Estimate It is estimated that the uiitial cost for mstaUation and initial mauitenance of the mitigation/revegetation effort for the 4.14 acres of wetland habitats required both onsite and m offsitewiUcostapproxunately$192,500. This cost amounts to approxunately $46,500/acre. This m cost estunate includes site preparation, grading, plantuig, temporary irrigation and maintenance through the end of the initial 120-day estabUshment period (instaUing contractor responsibUity including irutial revegetation mauitenance through the 120-day period). Revegetation construction monitoring would cost approximately $10,800 through instaUation and the 120-day m plant establishment period. Long-term mauitenance and biological monitoruig costs for the five- iM year period total approximately $81,000 (responsibUity of the City of Carlsbad). The cost of monitoruig and long-term mauitenance would be approxunately $22,000/acre. The total cost for the entire program wUl be $284,300 or approxunately $68,700/acre through the entire five-year period. These costs indude a 20 percent contingency factor for unforeseen costs as required by the resource agencies. These costs do not include the purchase price or other charges associated with acquisition of the offsite mitigation areas. DUDEK & ASSOCIATES, INC. 1576-9 Profaiiorud Teonu for CompEer Prt^tctt December 2000 20 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 2.2 Final Success Criteria The final success criteria outimed herein wUl be used to determine completion of the Applicant's mitigation responsibiUties. Fulfillment of these criteria shaU demonstrate that the mitigation areas are progressuig toward the habitat types, functions and values which wUl fulfUl the long- term goals of the mitigation effort. Success criteria wUl not be considered to have been met untU aU artificial support has ceased (e.g., supplemental irrigation has been terminated for a minunum of two years, container plant replacement complete, etc.), there is evidence of natural native plant recruitment, and the designated five-year mauitenance/monitoring period has been successfuUy ^ completed with approval of the resource agencies. See Section 3.1 for specific performance ^ standards. ^ 2.2.1 Existinq Functions and Values of IVIitigation Area m The proposed offsite mitigation area is currently composed of wetland habitats includuig li southem wiUow scrub, mule fat scmb, freshwater marsh and open water of varying degrees of disturbance and patch size and with significant amounts of exotic species invasion. The immediate creek area likely forms a corridor for dispersal of wUdlife species downstream to the west ofthe project area. Adjacent to the existing wetland vegetation vvithui proposed mitigation areas, annual grassland and disturbed habitat exists providing Umited habitat value. Due to the non-native species invasion of armual grassland and disturbed habitats, the existing functions and values of these upland areas serve primarUy as foraging and nestuig habitat for raptors and habitat for various wUdlife. The habitat to be created wUl improve the functions and values of the existing site by replacing low quality non-native habitat with higher quaUty native habitat and m reintroducing appropriate native overstory and understory species. These lower quaUty habitats ii wiU be replaced with higher quality southem wUlow scrub and freshwater marsh habitats. The ^ majority of the existuig patches of wetland habitat wUl be left intact and/or enhanced with ^ connections re-estabUshed to provide a more cohesive habitat. m The mitigation areas, through expansion of the riparian zone, should provide uicreased benefits ii to native wUdlife. Expanding the riparian zone wUl provide increased benefits to native wUdUfe by providing additional buffering effects from the adjacent development, mcreasing habitat diversity and increasuig foraguig opportunities. The existing disturbed habitats in their current condition actuaUy discourage native plant recolonization because of the level of disturbance adn the presence of the exotics which tend to out-compete the native species. m k m m k k k DUDEK & ASSOCIATES, INC. 1576-9 Profeuloiul Teonu fot CompUi Project, December 2000 21 m m k m k m m m Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 2.2.2 Target Functions and Values The long-term goal of the revegetation effort is to create a self-sustainuig riparian system composed of southern wiUow scrub and freshwater marsh habitats. The mitigation project should ultunately create habitats with appropriate native plant assemblages suitable for animal foraguig, nestuig and dispersal that are of better quality than the existing conditions of the site. The proposed mitigation site wiU provide uicreased habitat cover and buffer areas for wUdlife movement. The created and enhanced habitats are expected to develop ui successlonal stages, even though an appropriate quantity of native plant materials wiU be mstaUed initiaUy. Overstory and understory species are expected to substantiaUy estabUsh vvithin the uiitial five-year period to levels which should be self sustaining over the long term. Within the southern VTUIOW scrub areas, the wiUow trees are expected to reach approxunately 70 percent of their ultimate overstory cover by the end of the five-year mauitenance/monitoring period. Understory shrub and ground cover species in the southern wiUow scrub areas should reach 80 percent of their intended coverage withui the initial five-year period. The freshwater marsh areas are expected to develop quicker than the southern wUlow scrub areas il if sufficient wet conditions can be created/sustauied to encourage the growth. Adequate establishment is anticipated by the end of the third year. Natural recruitment of native freshwater marsh species is also anticipated during this period. CattaUs (Typha latifolia) typicaUy colonize freshwater marsh areas on theu own without being planted. Other species are Ukely to establish on their own from wind blown seed, wUdlife dispersal and through water-born seed. 2.2.3 Taroet Hydrological Regime The hydrological conditions within the San Marcos Creek wUl not be altered from the current m conditions due to unplementation of the proposed project. Development of the surrounding k watershed wiU affect the amount of water flow entering the drainage. As part of the proposed project, storm drains wiU be placed to drain under the roadway fiUs at the wetland impact locations and wUl help sustaui the remauiing southem wUlow scrub and freshwater marsh vegetation. DUDEK &ASS(X;iATES, INC. 1576-9 Fra/eutonol Team* fbr ComHalVoiecti DCCember 2000 22 Conceptual Wetland Midgadon and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project Regarduig the offsite mitigation area, it is envisioned that the mcrease in development m the surrounding areas (e.g.. University Commons) wiU lead to additional runoff in the drainages flowuig through the revegetation areas. This factor coupled with the excavation of the upland areas to lower elevations closer to avaUable groundwater should help sustaui the intended revegetation effort over the long term. The widening of the riparian corridor and excavation of upland areas to wetland elevations should help accommodate additional creek flow. 2.2.4 Target Jurisdictional Acreage to be Created and Enlianced The goal of the mitigatiorVrevegetation plan is to revegetate a total of 4.14 acres of wetland habitat includuig 2.2 acres of offsite creation, 1.40 acres of offsite enhancement and 0.54 acre of onsite restoration of jurisdictional wetland habitat. The offsite wetland creation and enhancement areas wUl be set aside in permanent open space as part of the University Commons proj ect (part of Fieldstone HCP) Umiting future use of the areas and preserving them ui perpetuity. 2.3 Proposed Mitigation Areas The proposed offsite mitigation areas are located along San Marcos Creek in the City of San Marcos, withui the University Commons Specific Plan area. The University Commons project was approved by the City of San Marcos in February 1991. Approvals included a specific plan, tentative map and development agreement. The majority of the specific plan area is currently owned by Brookfield Homes who is currently processing amendments to the existing entitlements withui the City of San Marcos. The offsite mitigation site described in this conceptual mitigation plan is within the Brookfield/Brouwer ownership portion of the specific plan area. As part of preparation of this conceptual mitigation plan, representatives of the City of Carlsbad have met with representatives of Brookfield Homes to discuss locating the mitigation site withui the Brookfield/Brouwer ownership and Brookfield Homes representatives have conceptuaUy agreed to the proposed mitigation site configuration and location (pers. comm., December 4, 2000, D. Poole, Brookfield Homes). The City of Carlsbad and Brookfield Homes wiU continue to m coordkiate development and mitigation plannuig associated with the Rancho Santa Fe Road and il University Commons proj ects. Ongoing coordination efforts wUl mclude design and planning for the implementation, maintenance and monitoring of the wetland mitigation site(s). m il k DUDEK & ASSOCIATES, INC. 1576-9 ProfculDna] TODU ^ Compla Project, December 2000 23 k k m Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 2.3.1 Location and Size of Mitigation Areas The proposed offsite mitigation and revegetation areas, totaUng 3.6 acres, are situated along San Marcos Creek south and east of the Rancho Santa Fe ReaUgnment and Bridge Replacement Project site. The proposed mitigation areas are located on either side of San Marcos Creek and east of the La Costa Meadows Busuiess Park. The mitigation sites wUl be located east of the future extension of Melrose Drive which wiU be buUt with the University Commons project. Vegetation along San Marcos Creek is domuiated by southern wiUow scrub, mule fat scrub, freshwater marsh, aimual (non-native) grassland and disturbed habitat. The creation acreage wUl occur within non-native upland areas composed of annual grassland and disturbed habitat (Figure 4). Southern wiUow scrub and freshwater marsh enhancement areas are located adjacent to creation areas and contain exotic/weedy plant species that would potentiaUy cause weed uivasion (Figure 6). Therefore, these areas were targeted for enhancement to improve the overaU quality of the habitat and to help assure success withui the creation areas (Figure 7). Plantings in these areas wiU be uistaUed during the winter and early spruig periods to take advantage of natural ramfaU and to minimize supplemental irrigation needs. Ongoing maintenance, weed control and exotic plant removals wUl be mcluded for these areas in the five-year maintenance program. Additional recmitment and colonization of native species wUl be encouraged. m 2.3.2 Present and Proposed Uses of Mitigation Area k At present, the proposed wetland creation areas consist of upland habitats including non-native armual grassland and disturbed habitat. The proposed wetland enhancement areas contain existing southern wiUow scrub, mule fat scmb and freshwater marsh wetland species. The m proposed mitigation/revegetation areas wiU provide uicreased wUdUfe habitat and expand native k wetland habitats. Additional native vegetation wiU help provide additional foraging opportunities ^ and native plant cover for wUdUfe species utiUzuig the riparian areas. ii The offsite mitigation site for the Rancho Santa Fe Road project is located entirely within the « Brouwer portion of the Brookfield/Brouwer ovmership. Brookfield Homes intends to convey the • portion of the Brouwer ownership east of the future extension of Melrose Drive, the area withui which the mitigation site is located, in fee title to the Environmental Trust for long-term morutoring and management. To ensure that the wetland mitigation program is appropriately implemented and monitored, easements wiU be granted to the City of Carlsbad and Brookfield ^ Homes for unplementation and monitoring of the mitigation program. An open space easement k DUDEK & ASSOCIATES, INC. 1576-9 Prafustovuil I^OMU for CompUx Projtctt December 2000 24 Conceptual Wetland Mitigation and Monitoring Plan - Rancho Santa Fe Road Revised Conceptual Revegetation Plan (Offsite Location at University Commons) FIGURE 6 u Photo 1: Northeast facing view of existing southern willow scrub. Photo 2: North facing view of existing southern willow scrub. Photo 3: Northeast facing view of the open channel. Photo 4: Southwest facing view of the open channel and existing southern willow scrub. Photo 5: Northeast facing view of proposed wetland mitigation site. Conceptual Wetland Mitigation and Monitoring Plan • Ranclio Santa Fe Road Site Photographs FIGURE m k m m Conceptual Wedand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project covering the entue Brouwer ownership, east of the future extension of Mekose Drive, wUl be granted to the City of San Marcos to ensure the long-term conservation of the property, includuig the wetland mitigation/revegetation sites. 2.4 Implementation Plan The foUowing plan describes the necessary unplementation measures for creatuig and enhancing the rntended habitats and unplementing the uitended mitigation and revegetation program. 2.4.1 Rationale for Expecting Implementation Success The areas to be revegetated are unmediately adjacent to existmg riparian habitat, mdicating appropriate conditions exist to support these wetland species if grade alteration and weed eradication can be completed. Graduig wUl be conducted to create appropriate elevations for expanduig the riparian habitat. The surrounding native habitat species compositions were used as reference for the revegetation habitat compositions. HeavUy invasive non-native and exotic species that have displaced desirable native species within the revegetation areas wUl be removed. The intent is to help create more naturaUy diverse native habitats that wUl be able to muumize exotic and weed invasions. Where appropriate, native plant materials grown from sources coUected from the local coastal San Diego area wUl be used tn order to preserve genetic integrity and uicrease the potential for long-term success and sustainabUity. Because areas adjacent to the proposed revegetation areas presently support wetland species, the probabUity of successful revegetation of the uitended habitat types based upon the estabUshment of simUar elevations and hydrological conditions onsite is high. The surface hydrology and groundwater conditions appear to be appropriate, if modifications through excavation to estabUsh appropriate water table elevations can be made to support successful growth and sustainabUity of the various vegetation types. The soUs may have to be manipulated through excavations and possibly supplemented with soU amendments in order to encourage the revegetation program and m optimize plant growth. m ^1 il m As part of the final landscape/revegetation construction documents (plans and specifications), to be prepared at a later date by a Landscape Architect/Habitat Restoration Designer, soU preparation recommendations wUl be provided based upon soUs analyses taken from the proposed revegetation areas. Final soU sampling and additionai analyses also wUl be required of the contractor after grading to verify soU fertUity and agricultural suitabiUty recommendations prior DUDEK & ASSOCIATES, INC. 1576-9 Pmfenfanul Tionu ^ Compla Pnijccu December 2000 27 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project m m k m to plantmg. This uiformation wUl be utUized to estabUsh final soU amending/conditioning measures as necessary to correct poor soU conditions and to aUow for successful contauier plantuigs and seeduig. Amenduig of the soU backfiU for contauier plants may be necessary to correct deficient soU conditions if they exist in the areas proposed for planting. To the greatest extent possible, the revegetation effort has been focused in aUuvial soU deposits where a more fertUe soU profUe is present. Implementation procedures wUl be outlined further ui subsequent sections and on the final revegetation plans and specifications. 2.4.2 Preliminap/ Schedule The revegetation program which provides mitigation for permanent and temporary impacts is contuigent upon the approval of this conceptual wetland mitigation plan by the resource agencies and local jurisdictions. Upon appropriate approvals, the implementation of the revegetation program could begin in the winter of 2001. Implementation Tasks Schedule in m m m m m m Contract growing agreement with nursery OveraU mitigation site graduig Site Preparation and weed/exotic removal InstaUation of temporary irrigation system Planting container stock Hydroseed application Completion of InstaUation/Assessment of revegetation effort Year 1 monitoring Spring and faU of year Year 2 monitoring Year 2 remedial efforts (if required) Year 3 monitoring Year 3 remedial efforts (if required) Year 4 monitoruig Year 4 remedial efforts (if required) Year 5 monitoring Year 5 remedial efforts (if required) Final Sign-Off No later than nuie months prior to plantmg Summer/FaU of implementation year Fall/Winter foUowuig grading Winter/Spring foUowing site preparation Spruig foUovidng irrigation instaUation Spruig foUowing plantmg FaU foUovmig completion of construction and 120 day maintenance period one foUowing completion of instaUation phase Spruig and FaU of foUowing year Spring/Summer of foUowuig year Spring and FaU of foUowing year Spring/Summer of foUowing year Spring and FaU of foUowuig year Spruig/Summer of foUowuig year Spring and FaU of foUowing year Spring/summer of foUowing year FaU/Winter of Year 5 DUDEK & ASSOCIATES, INC. 1576-9 I^o/uflanat Teomi ^ Complex PiDjecti December 2000 28 il ii Conceptual Wedand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 2.4.3 Site Preparation The initial site preparation effort necessary to prepare the revegetation areas wiU include the removal of aU non-native weed and exotic species from the limits of the creation, enhancement and restoration areas, including but not limited to eucalyptus trees (Eucalyptus ssp.), pampas grass, pampas grass^ salt cedar (Tamarixramosissima), sweet fennel (Foeniculum vulgare), artichoke thistle {Cynara cardunculus), sweet clover (JVlelilotus sp), bristly ox-tongue (Pieris echioides), black mustard (Brassica nigra), castor bean (Ricinus communis), tree tobacco (Nicotianaglauca), cocklebur (Xanthium sp.)and other uivasive exotics from the limits of the mitigation areas. AU eucalyptus, salt cedar, giant reed and other highly invasive/exotic species, as identified in Sections 2.5. id and 2.5.2 and as tagged by the biological monitor/habitat restoration specialist, shaU be physicaUy removed and/or cut down and treated with an herbicide, where necessary, and removed from the " site. Remauiuig trunks shaU be treated with a stump kiUer and periodicaUy sprayed with an *" herbicide to help controi re-sprouts. Although not within the unmediate mitigation areas, the mm physical/mechanical removal of any giant reed rootbaUs and aU associated cut vegetation may be m necessary if giant reed colonizes the area duruig the maintenance period. AU cut vegetation from giant reed wUl be disposed of at an acceptable off-site source or landfiU facUity. Any giant reed *" clumps which are intertwined vdthin existing native vegetation, which would preclude mechanical removal, shaU be cut back to the rootball by hand and sprayed with an acceptable m herbicide as specified by a Licensed Pest Control Advisor. m If tree removal occurs during the migratory bird nesting season, a focused avian nestuig survey * shaU be performed by a qualified wUdUfe biologist two days prior to tree removal in accordance with the Migratory Bird Treaty Act (16 U.S.C. 703-712). T3^icaUy, birds ui southem CaUfornia Ml nest between March 15 and August 31. Results shaU be documented m writing and forwarded M to the permittuig agencies. If nesting birds are detected, the vegetation within the nest location shaU be protected untU fledging has occurred. ii m In order to create appropriate wetland habitat, the revegetation areas wiU be excavated to plantmg levels compatible with the existing vegetation and/or within reasonable distance to groundwater elevations. Finai grading plans for the revegetation areas wUl be prepared by the proj ect civU enguieer in coorduiation with the Landscape Architect/Habitat restoration specialist based on the intent of this conceptual mitigation plan. Wetland grading plans for the revegetation areas shaU be incorporated into the final project gradmg plans or revegetation landscape plans. DUDEK & ASSOCIATES, INC. 1576-9 PrD^euional leanu far Complcr PrufBctt December 2000 29 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project Fuial soUs analyses shaU be initiated by the contractor after rough grading of the revegetation areas is completed to verify whether additional soU remediation measures (i.e., amending/ conditioning) wiU be necessary. This wiU include representative soU sample analyses, completed by a soUs testing laboratory, from each of the uitended revegetation areas to determuie agricultural- suitabUity and soU fertiUty. Recommendations shaU be provided on the final landscape plans (plans and specifications) for soU amending if necessary. SoU augering of the container plant pits for tree species wUl also be required to help faciUtate roots reachuig the avaUable water table. 2.4.4 Final Landscape/Revegetation Plans A final set of landscape construction documents (plans and specifications) including planting plans, irrigation plans, uistaUation detaUs and specifications (instaUation and maintenance requirements) shaU be prepared by a Landscape Architect/Habitat Restoration Designer. The plans shaU be acceptable for bidding and shaU be prepared to implement the conceptual guidelines for the revegetation program outlined in this document. Implementation of the revegetation program must be coordmated among the AppUcant, Landscape Architect/Habitat restoration specialist, landscape contractor and plant material suppliers. The contracting nursery and seed coUectors should be given the maxunum possible lead tune (i.e., no less than mne months prior to actual planting instaUation) to complete special coUections and prepare plant materiai for the project in order to assure avaUabUity and to minunize cost. Field coordination shaU be provided by the biological monitor/landscape architect for construction of the mitigation/revegetation areas. Species to be planted in the revegetation areas are shown on the plant palette Tables 3 through 6, which indudes the revegetation plant materials and seed for the proposed project. The conceptual revegetation areas are graphicaUy depicted on Figure 6. The nursery that provides plant materials should be contacted immediately foUowing approval of the plan to aUow a muiimum of mne months to grow material prior to instaUation. Few nurseries have experience deaUng with native plants, especiaUy those species not used for ornamental purposes. An experienced native plant nursery such as Tree of Life nursery in San Juan Capistrano, Mockuigbud Nursery in Paverside, or an approved equal, should be contracted with to coUect propagules and supply the necessary contauier grown plant material. A deposit wUI be required to initiate the contract growing agreement. A seed supplier specializing ui native species, such as S&S Seeds in Carpenteria, or an approved equal, should be contracted v^ith to supply the necessary seed. DUDEK & ASSOCIATES, INC. 1576-9 Pro^inoW Teonu f<>rC<>nipleiProiecU DCCember 2000 30 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project Appropriate tunuig of planting may decrease or eUminate the need for supplemental watermg and wUI uicrease the survival of the plants. The best survival rates are achieved when planting is achieved between 15 November and 15 AprU. Planting at the site should be accompUshed during the late vmiter/early spruig immediately after the hazard from winter flooduig has subsided. Some contauier plantuigs might be aUowable ui the late faU or early wkiter of the year, per biological monitor approval, if the areas for plantmg are outside the area of flooduig. This wiU be determined based upon the final unplementation schedule, upon actual field conditions and nursery supply schedules. Hydroseedmg should be timed to take advantage of seasonal rainfaU patterns and should be appUed between faU and spring, if possible. Planting areas to be irrigated could be seeded outside of this time frame. In September, foUowing the first summer after instaUation, the plants should be checked for viabUity (i.e., number of dead container plants). Sufficient replacement plants shaU be instaUed duruig the mauitenance period ui order to help achieve the year-end standards as defined in Section 3.1 performance standards (i.e., 100 percent survival contauier planted trees, 90 percent shrubs). The dead plant material shaU be removed and replaced with the same size material as was planted origuiaUy. Replacement planting should be completed ui the f aU of each year. The viabUity check Ul September should be part of the technical assessment described ui the Monitoring Plan, Section 3.(9 of this report. 2.4.5 Temporary Irrigation System The goal of the wetland revegetation program is to create, enhance and restore a functioning riparian system to both the onsite and offsite locations capable of mauitauiuig and supportmg the habitats in perpetuity. Native plants may, however, require temporary krigation for establishment when they have been grown in nursery containers and are planted under initiaUy dry site conditions. In addition, it may not always be feasible to instaU the intended plant materials under the ideal seasonal plantmg conditions based upon construction and grading schedules. Thus, a temporary krigation system is beneficial to supplement the natural rauifaU conditions and to stimulate initial plant growth and promote establishment. The landscape contractor shaU instaU a temporary overhead spray irrigation system for all contakier-planted and seeded areas based upon final krigation plans prepared by the landscape architect. Supplemental hand-watering shaU be accommodated by the instaUation of quick coupling valves as part of the irrigation system in order to initiaUy water-in the plant material and DUDEK & ASSOCIATES, INC. 1576-9 Pn/ieutotuI Teonu for CompUx Frojtcts December 2000 31 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project to supplement the irrigation system when necessary. The irrigation system shaU be fed from potable water or reclauned water source(s) off water meter(s) from the nearest possible sources. Crosskigs of the drainages with irrigation mainlme or lateral Une should be mkiknized or avoided altogether, where possible, to avoid wash-out problems. The system should be instaUed for temporary use for approxknately three years and then discontkiued once the plant materiais have become adequately estabUshed. The system should be completely abandoned prior to the end of the five-year maintenance/monitoring period. To be acceptable to the resource agencies, the system use shaU have been discontinued for two years prior to acceptance. AU overhead spray irrigation system components shaU be completely removed from the site prior to the end of the maintenance/ monitoring period. Irrigation shaU be used solely for the purpose of estabUshuig vegetation on the mitigation site and is to be considered temporary in nature. The revegetated areas shaU be overhead spray-krigated during the drier periods of the year untU the plant materials are adequately estabUshed to survive on natural site conditions. Irrigation should be graduaUy withdrawn based upon dkection of the biological monitor/habitat restoration speciaUst. 2.4.6 As-Built Conditions The Applicant shaU submit a report to the ACOE and CDFG withki sbc weeks of completion of site preparation and planting, acknowledging the completion of the instaUation phase and documenting the as-buUt status of the mitigation project. The report shaU include a plan or map diagram showkig the mitigation area and the final as-buUt locations of plantings and other uistaUations. Photographs shaU also be uicluded to document the completion of the monitoring period and the final site conditions. 2.5 Maintenance During l\/lonitoring Period The purpose of the monitoring program is to provide guidelines for makitenance of the revegetated habitat. Because the goal of the revegetation program is to create a natural system that can support itself with little or no maintenance, the primary effort of the maintenance/ monitoring program is concentrated in the first few seasons of growth to control weeds and promote plant and seed growth. The preserved patches of southern wiUow scmb, freshwater marsh and other wetland resources should also be maintained to control weeds and exotic plant growth. (DUDEK &ASSCX;iATES, INC. 1576-9 profeMi<mfliT*au/»rCo«*ic< Proieci, December 2000 32 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 2.5.1 a) b) c) d) e) Maintenance Activities The revegetated areas shaU be urigated with an overhead spray system durmg the drier parts of the year, primarUy the summer months. Irrigation systems shaU be adequately makitakied to assure coverage of aU contauier planted and seeded areas as uidicated on the fuial plans. Irrigation should last for approxunately three years and be phased out per biological monitor/habitat restoration specialist direction prior to the end of the five-year maintenance and monitoruig period. The plantuigs should survive two summers without supplemental irrigation to demonstrate adequate estabUshment to the resource agencies. Native understory species wUl not be cleared ki the revegetated areas. Only non- native, exotic/invasive plant material and weeds shall be cleared. Additional vegetation thinning of native species, if necessary, must be authorized by the biological monitor/habitat restoration speciaUst. GeneraUy, no pruning or clearing of vegetation in the wetland areas wiU take place after the third year. GeneraUy, the site wiU not be fertUized durkig the mamtenance period unless determined necessary by the biological monitor as a remedial measure to correct soU deficiencies. The native riparian vegetation wUl not be pruned unless so dkected by the biological monitor. Non-native/exotic species and weeds may invade the revegetation sites and may become a problem before or durkig the estabUshment of the intended native plant associations. The primary exotic/invasive, non-native species mcluding pampas gras^ salt cedai; castor bean, eucalyptus and tree tobacco should be hand removed as soon as they begki to invade and before they become too large for hand extraction. An approximate 90 percent exotics/weed-fiee condition should be makitakied throughout the five-year maintenance period for these species. Other weed species to be controUed are identified in Section 2.5.2. Dead contauier plant material shaU be replaced each year, per the appropriate percentages, as defined ui the success criteria. & ASSOCIATES, INC. 1576-9 ProjWulofluil Tdiiu for Compltx Pnjecti December 2000 33 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Projea 2.5.2 General Habitat Maintenance Guidelines Irrigation: The krigation system for the revegetation areas should be temporary m nature and shaU be abandoned/left ki place or removed once the plantkigs are adequately estabUshed. The mauitenance contractor, in consultation with the biological monitor/habitat restoration specialist, shaU determine the tunuig for termkiation of the irrigation system. Irrigation components, such as valves and sprmkler heads, may be salvaged for re-use elsewhere as dkected by the Applicant. AU above-ground pipe and components shaU be removed. Below-ground components shaU be abandoned in place and/or salvaged as possible. Dead Plant Replacement: AU dead contauier plant materials above the aUowable tolerance levels, as defined in the Performance Standards (Section 3.1), shaU be replaced with the same species and ui the same size containers as originaUy specified (see Stetion 2.1.1 original species compositions). Weed Control: Weed control measures shaU include the foUowing: (1) hand removal, (2) cuttkig or mowing, (3) chemical herbicides, (4) light exclusion. Hand removal of weeds is the most desuable method of control and shaU be used around individuai contauier plantings. Other secondary weeds, other than those mentioned in Section 2.5.1 d, such as sweet fermel, black mustard and bristly ox-tongue should be hand removed before they set seed. Cuttkig or mowing can be the most practical method but requires that makitenance personnel be able to accurately differentiate between native plantuigs and non-native weeds. Because these species are fast growing, it is critical that they are controUed before they shade and out-compete revegetation plantings. Chemical control and/or physical/mechanical removal shaU be used for the highly invasive exotics and weeds. The biological monitor/habitat restoration specialist should coordinate with the maintenance contractor to identify specific sites where chemical herbicides may be used. Any herbicide treatment must be specified by a Ucensed Pest Control Advisor and appUed by a Ucensed Pest Control AppUcator. Light exclusion entaUs temporarUy covering the soU with a material which blocks Ught to the soU surface thus uihibiting weed growth. Such coverkigs may include organic mulch, landscape/weed fabric, compost, or straw. AIO percent total cover of secondary weed species wiU be tolerated at the end of the five-year maintenance period. This means that 90 percent of the revegetation site shaU be weed/exotic-free. Clearing and Trash Removal: Prunkig or clearing of existing and/or planted native vegetation wUl not be aUowed within the nutigation/revegetation areas unless so dkected by the biological monitor/habitat restoration speciaUst. Deadwood and leaf Utter of native trees and shmbs shaU DUDEK & ASSOCIATES, INC. 1576-9 Projeuionol Teonu for Coinplei Project, December 2000 34 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project not be removed. Downed logs and leaf litter provide valuable microhabitats for kivertebrates, reptUes, smaU mammals and buds. In addition, the decomposition of deadwood and leaf Utter is essential for the replenishment of soU nutrients and mkierals. Non-organic trash and debris wiU be removed from the revegetation site by hand on a regular basis, at no less than one-month intervals, for the first year and then quarterly thereafter. Trash consists of aU man-made non- organic materials, equipment, or debris dumped, thrown, or left withki the mitigation/ revegetation areas. 2.5.3 Schedule of Maintenance/Monitoring Inspections The biological monitor/habitat restoration speciaUst wiU conduct quarterly mauitenance inspections during the five-year morutoring period. Recommendations for makitenance efforts wUl be based upon these site observations. Weed removal bythe mauitenance contractor should be conducted on a bi-weekly basis for the first year and monthly thereafter. 3.0 MONITORING PLAN Monitoring of the mitigation/revegetation sites has a two-fold purpose: 1) To monitor the progress of mitigation/revegetation plantuigs by comparing quantitative measures, such as density, percent coverage, mortality and species diversity, with the performance standards; 2) To duect and monitor the maintenance activities through qualitative methods and determkie remedial actions in a manner that ensures proper and appropriate mauitenance occurs on a timely basis. Weed control and herbivory are particularly important maintenance issues that often require ongokig attention from mauitenance persormel. The quaUtative (visual) assessments of the habitats shaU be performed by a quaUfied biologist/habitat restoration specialist. 3.1 Performance Standards The foUowing performance standards shaU be achieved at the end of each year foUowing plantuig within the creation, enhancement and restoration areas. Performance standards are viewed as interim project objectives designed to achieve the final mitigation goal. If mitigation efforts faU to meet performance standards in any one year, the biological monitor/habitat restoration SpeciaUst should recommend remedial actions to be implemented the foUowuig year that wUl enhance the project to a level of conformance with the origkial standard. DUDEK & ASSOCIATES, INC. 1576-9 Projuilona] Teonu^ Compla Projecti December 2000 35 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Repiacement Project Southern Willow Scrub Habitat (creation, enhancement and restoration areas) First Year Performance Standards: 100 percent survival of aU contakier planted tree species 90 percent survival of aU contauier planted shmb species 40 percent total coverage of container planted tree and shrub species combkied 10 percent coverage of seeded species 90 percent weed and exotics free Second Year Performance Standards: 90 percent survival of aU container planted tree species 80 percent survival of aU container planted shrub species 50 percent coverage of container planted tree and shrub species combined 15 percent coverage of seeded species 90 percent weed and exotics free Third Year Performance Standards: 90 percent survival of all contakier planted tree species 80 percent survival of aU contakier planted shrub species *60 percent coverage of tree and shrub species combined *20 percent coverage of seeded species *10 foot mean height for arroyo v^^ows 90 percent weed and exotics free (* per quantitative transect measurements) Fourth Year Performance Standards: 90 percent survival of aU container planted tree species 80 percent survival of aU container planted shrub species *70 percent coverage of tree and shrub species combined *25 percent coverage of seeded species *15 foot mean height for arroyo wUlows 90 percent weed and exotics free (* per quantitative transect measurements) DUDEK & ASSOCIATES, INC. 1576-9 Pro/iuiioiui] Teanu for Compla Proitcta December 2000 36 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project Fifth Year Performance Standards: 90 percent survival of aU container-planted tree species 80 percent survival of aU container-planted shrub species *80 percent coverage of tree and shrub species combined (approximately 70 percent canopy cover for wiUows and 10 percent cover for shrubs) *30 percent coverage of seeded species *20 foot mean height for arroyo wiUows 90 percent weed and exotics free (* per quantitative transect measurements) Freshwater Marsh Habitat (creation and enhancement areas) First Year Performance Standards: 100 percent survival container planted species. 30 percent coverage of native species (planted and volunteer) 90 percent weed and exotics free Second Year Performance Standards: 90 percent survival contakier planted species 40 percent coverage of native species 90 percent weed and exotics free Third Year Performance Standards: 90 percent survival contakier planted species 50 percent coverage of native species 90 percent weed and exotics free Fourth Year Performance Standards: 90 percent survival container planted species 60 percent coverage of native species 90 percent weed and exotics free Fifth Year Performance Standards: 90 percent survival container planted species 70 percent coverage of native species 90 percent weed and exotics free 1576-9 pn>feut«ioi Teonu jbr c<«iHe> Project, December 2000 37 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 3.2 Monitoring Methods Monitorkig shaU consist of field monitoring visits during September of the first year after planting and then during the spring and faU of each year thereafter by a quaUfied biological monitor/habitat restoration specialist. Spring monitoring visits wiU kiclude quantitative data coUection of sample transect measurements and random measurements of heights of individuals. Spring monitoring sessions in year three should determine the need to contkiue the temporary irrigation through the foUov^ing year. FaU monitoring visits wUl include qualitative evaluation of percent cover based on visual analysis. FaU monitorkig should be conducted to assess plant mortality and compUance with the intended yearly standard and need for dead plant replacements. Permanent vegetation transect pokits wiU be estabUshed within the mitigation sites at appropriate representative locations. Transects shaU be used to determkie compUance and achievement of the revegetation success standards; there wiU be a minimum of seven transects instaUed within the southern wiUow scrub revegetation areas. Permanent photo-documentation stations wiU be established along each vegetation transect to record the progress of the mitigation program and to document plant establishment over the five-year period. Other representative photographs shaU be taken from general vantage points for aU creation, enhancement and restoration areas to show the overaU development of the areas. 3.3 Annual Reports A report outlining the results of the armual monitoring surveys based upon the anniversary date of the instaUation, shaU be submitted to the AppUcant, the ACOE and CDFG by the end of each year's monitoring period, through the end of the five-year period. The monitoring reports shaU describe the existing site conditions, identify aU shortcomings of the revegetation program, and recommend remedial measures necessary for the successful completion of the revegetation program and to demonstrate compliance with the appropriate permit conditions. The reports also v^ include the foUowing: 1. A Ust of names, titles and companies of aU persons who prepared the content of the aimual report and participated ui monitoring activities; DUDEK & ASSOCIATES, INC. 1576-9 Pro/euliMal Team, ^ Confilex Project, December 2000 38 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 2. A copy of the ACOE permit, CDFG permit, any special conditions and any subsequent letters of modification to the origkial permits; 3. Copies of representative monitoring photographs; 4. Maps identifying monitorkig areas, transect locations, planting zones, etc. as appropriate; 5. Ouantitative data from transect measurements, per area. 3.4 Schedule for Monitoring The revegetation effort should be assessed in September followmg the fust summer after plantmg to determine mortaUty of kidividual contauier plants, initial success of the seeding effort and functionkig of the krigation system. Thereafter, the site shaU be monitored twice per year for five years, once in the spruig (quantitative data coUection) and once in the faU (qualitative evaluation), with year-end reports produced each year at the anniversaiy date of the completion of the instaUation. 3.5 Completion of Mitigation 3.5.1 Notification of Completion If the AppUcant beUeves that the final success criteria have been met at the end of the five-year monitoring period, the Applicant shaU notify ACOE and CDFG upon submitting the annual report for the final year and request acceptance of the site and release from the permit conditions. Early release may be possible if success criteria/performance standards are met early and the resource agencies concur with the level of establishment and agree to release the project from the permit requkements. 3.5.2 Regulatory Agency Confirmation FoUowing receipt of the notification of completion, the ACOE and CDFG may visit the ske to confirm the completion of the mitigation effort and issue letters of formal acceptance. Any remainkig bond monies would also be granted release at that tune. DUDEK & ASSOCIATES, INC. 1576-9 Profrutoiai Teonu for Comple. Project. DeCembef 2000 39 Conceptual Wetiand Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project 3.6 Contingency Measures 3.6.1 Procedures for Initiating Contingency Measures If an annual performance criterion is not met for aU or any portion of the mitigation proj ect in any year or if the 'final success criteria are not met, the Applicant shaU prepare an analysis of the cause(s) of faUure and, if determined necessary by the ACOE and CDFG, propose remedial contuigency measures for approval. If the mitigation site has not met the performance criteria, the responsible party's makitenance and monitoring obligations wiU continue or alternative contingency measures wUi be negotiated untU the ACOE and CDFG give final project permit compliance/approval. 3.6.2 Funding Mechanisms The same funduig source for the intended mitigation proj ect, as established by the Applicant, wiU provide funding for any additional planning, implementation and monitoring of any contingency procedures that may be required to achieve the mitigation goals. 4.0 ACKNOWLEDGMENTS This report was prepared by DUDEK staff John L. Mkichki (Landscape Architect#2225S/Habitat Restoration SpeciaUst) and Myloc Nguyen (Biologist/Habitat Restoration SpeciaUst) with review by the project manager Sherri L. MiUer (Biologist). Graphics and GIS mappuig and analyses were provided by Lesley Terry; Tonette S. Foster provided word processing. LITERATURE CITED AND REFERENCED Dudek & Associates. AprU 2000 Draft Biological Resources Report and Impact Analysis Rancho Santa Fe Road Realignment and Bridge Replacement Project. City of Carlsbad, Califorrua. Dudek & Associates. AprU 2000 Rancho Santa Fe Road Realignment Project Pre-Construction Notification for Nationvcide Permits 14, 18, and 33. City of Carisbad, CaUfomia. DUDEK & ASSOCIATES, INC. 1576-9 Proffuioiial Taimi for CompUx Projed] December 2000 40 Conceptual Wetland Mitigation and Monitoring Plan Rancho Santa Fe Road Realignment and Bridge Replacement Project Dudek & Associates. AprU 2000 Request for Water Quality Certification forRancho Santa Ft Road Realignment Project. City of Carlsbad, CaUfomia. Hickman, J. C. 1993. The Jepson Manual: Higher Plants of California. University of California Press, Berkeley. 1400 pp. HoUand, R. F. 1986. Preliminary Descriptions of tht Ttrrtstrtal Natural Communities of California. Nongame-Heritage Program, CaUfornia Department of Fish and Game. Reed, P.B., Jr. 1988. National List of Plant Sptcits that Occur in Wttlands: California (RegionO). U.S. Fish and WUdUfe Service Biological Report. 88(26.10). U.S. Army Corps of Engineers. January 1987. 1987 U.S. Army Corps of Engineers Wetland Delineation Manual (TR Y-87-1). & ASSOCIATES, INC. 1576-9 Profeulimiil Teani for CompUx PrDjecti December 2000 41