HomeMy WebLinkAboutEIR 03-05; PRECISE DEVELOPMENT PLAN AND DESALINATION PLANT; 2ND ADDENDUM TO PRECISE DEVELOPMENT PLAN AND DESALINATION PLANT PROJECT; 2012-11-01
SECOND ADDENDUM
PRECISE DEVELOPMENT PLAN AND DESALINATION PLANT PROJECT
FINAL ENVIRONMENTAL IMPACT REPORT (EIR 03-05)
CITY OF CARLSBAD, CALIFORNIA
State Clearinghouse No. 2004041081
EIR Certified June 13, 2006
Prepared for:
San Diego County Water Authority
4677 Overland Avenue
San Diego, California 92123
Prepared by:
Dudek
605 Third Street
Encinitas, California 92024
November 2012
Precise Development Plan and Desalination Plant Project November 2012
Second CEQA Addendum 1
Acronyms and Abbreviations
Acronym/Abbreviation Definition
AMSL above mean sea level
BSRA Biologically Significant Resource Areas
CARB California Air Resources Board
CCR California Code of Regulations
CEQA California Environmental Quality Act
dB decibel
EIR Environmental Impact Report
EIS Environmental Impact Statement
EPS Encina Power Station
ERP Emergency Response Plan
FEIR Final Environmental Impact Report
gal/day Gallons per day
GHG greenhouse gas
GHG Plan Energy Minimization and Greenhouse Gas
Reduction Plan
HCP Habitat Conservation Plan
HMA Habitat Management Area
MBTA Migratory Bird Treaty Act
mgd million gallon per day
MWD Metropolitan Water District of Southern California
NCCP Natural Community Conservation Plan
PDP Precise Development Plan
REC Renewable Energy Credit
ROW right-of-way
SDG&E San Diego Gas and Electric
SWPPP Stormwater Pollution Prevention Plan
TOVWTP Twin Oaks Valley Water Treatment Plant
VWD Vallecitos Water District
USFWS U.S. Fish and Wildlife Service
Water Authority San Diego County Water Authority
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Second CEQA Addendum 2
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Second CEQA Addendum 3
1.0 INTRODUCTION/PROJECT BACKGROUND
The City of Carlsbad prepared and certified the Carlsbad Precise Development Plan and
Desalination Plant Final Environmental Impact Report (FEIR) (City of Carlsbad 2006) and First
Addendum (City of Carlsbad 2009) for the Carlsbad Desalination Project (Project). The FEIR
analyzed all components of the Project, including a 50 million gallon per day (mgd) seawater
desalination plant and off-site water conveyance facilities located within the cities of Carlsbad,
Oceanside, and Vista. The First Addendum documented changes to the footprint of the
desalination plant and off-site water conveyance facilities. Pursuant to Section 15367 of the
California Environmental Quality Act (CEQA), the City of Carlsbad was the lead agency for the
preparation of the FEIR. The FEIR documented that agencies other than the City of Carlsbad
will use the FEIR when making a decision on aspects of the Project that require their approval.
As noted in Section 3.4.2 of the FEIR, the product water created at the seawater desalination
plant would be transmitted to local and/or regional storage and distribution systems. The
delivery area for the product water was expected to include a number of local water agencies,
municipalities, and the San Diego County Water Authority (Water Authority) and its member
agencies. The Project described in the FEIR included the construction of new off-site pipelines
that would need to be constructed to convey the product water to the City of Carlsbad,
neighboring water agencies, and/or the Water Authority. Although multiple alternative pipeline
alignments were analyzed by the City of Carlsbad in the FEIR, the analysis did not include
potential impacts associated with modifying the Water Authority’s facilities that would convey
product water to the Water Authority distribution facilities (City of Carlsbad 2006).
In support of its mission, the Water Authority has determined that purchasing product water from
the Project would improve long-term water supply reliability for the San Diego region. The
Water Authority has been working closely with several of its member agencies and the Project
proponent, Poseidon Resources, regarding a water purchase agreement for potential Water
Authority-owned local supply (of product water) from the Project.
The Water Authority has determined that minor changes to the previously approved off-site
distribution system are necessary to allow for greater operational flexibility and efficiency in
receiving and delivering the product water from the Project. Pursuant to Section 15381 of
CEQA, the Water Authority is a responsible agency for the preparation of this Second
Addendum to the Project’s FEIR. The purpose of this Second Addendum is to evaluate the
potential for environmental effects of the Water Authority’s proposed minor modifications to the
approved off-site water conveyance facilities and to determine if these modifications would
result in any new significant impacts or any substantial increase in the severity of impacts
addressed under the certified FEIR, as amended by the First Addendum.
To enhance the safety and reliability of deliveries from the Project to the Water Authority’s
aqueduct system, the Water Authority is proposing minor modifications to the Project scope
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Second CEQA Addendum 4
previously approved in the FEIR. Specifically, these include modifications at the Twin Oaks
Valley Water Treatment Plant (TOVWTP), Pipeline 3 relining between San Marcos and the
TOVWTP, modifications to the pipeline interconnection facilities at San Marcos, modifications to
the Pipeline 4 San Marcos Vent Structure, and an alternative pipeline alignment near Cannon
Road and Faraday Avenue. These improvements are under consideration to ensure the
desalinated product water can be safely and reliably integrated into the Water Authority’s
existing regional distribution system. A description and purpose for each of these modifications
is further discussed in Section 5.0.
On June 13, 2006, the City of Carlsbad approved the FEIR for the land use approvals to
construct and operate the approximately 50 mgd Carlsbad Seawater Desalination Plant
(desalination plant) adjacent to the Encina Power Station (EPS). The FEIR also analyzed 17.4
miles of off-site conveyance pipelines, as well as ancillary facilities to carry and store product
water from the desalination plant (City of Carlsbad 2006). The FEIR included analysis of
multiple options for the water conveyance pipelines, to allow for flexibility in the final design. To
ensure that all impacts associated with the ultimate pipeline alignment were addressed, the
FEIR considered at an equal level of detail the impacts associated with two primary pipeline
alignment options, as well as several sub-alignments, though only one alignment was actually
going to be built.
On September 15, 2009, the City of Carlsbad approved an Addendum to the FEIR (First
Addendum), which documented changes to the footprint of the desalination plant and off-site
water conveyance facilities. The pipeline alignment considered under the First Addendum
consisted of approximately 16.2 miles of pipeline (a 7% reduction from the pipeline length
analyzed in the FEIR). Additionally, with the pipeline alignment addressed under the First
Addendum, environmental impacts associated with several segments of pipeline that were
evaluated and mitigated for in the FEIR were avoided. Thus, the proposed project under the
First Addendum represented reduced environmental impacts as compared to the impacts
covered under the FEIR (City of Carlsbad 2009).
In addition to the FEIR and the First Addendum, one other approved CEQA document is relevant
to the currently proposed Project changes. The Water Authority prepared a Final Environmental
Impact Report/Environmental Impact Statement (FEIR/EIS) for the San Diego County Water
Authority Subregional Natural Community Conservation Plan/Habitat Conservation Plan
(NCCP/HCP) in October 2010 (Water Authority 2010a). This document is relevant in that it
addresses potential impacts of Water Authority covered activities on sensitive biological resources
and results in issuance of a federal incidental take permit pursuant to Section 10(a)(1)(B) of the
Endangered Species Act and State take permit pursuant to Section 2835 of the California Fish
and Game Code. The federal and State permits require, and the associated NCCP/HCP
implementing agreement contractually binds, the Water Authority to implement applicable project
design features and mitigation measures on a project by project basis when conducting covered
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Second CEQA Addendum 5
activities in or adjacent to covered species habitats. Covered activities include new construction
and typical expansion of existing infrastructure, as well as ongoing installation, use maintenance,
and repair of aqueduct and water conveyance, treatment, and storage systems. Activities
associated with the proposed Project modifications are subject to the biological requirements and
mitigation measures in the aforementioned Carlsbad FEIR and the First Addendum, with the
exception of the application of biological mitigation to the proposed Twin Oaks Valley Water
Treatment Plant Modifications, Pipeline 3 Relining, and Pipeline 4 Vent Replacement and
Pipeline Interconnect components. The Water Authority is substituting its NCCP/HCP mitigation
measures to address biological impacts for these proposed Project components, because it is
contractually obligated to apply NCCP/HCP requirements and mitigation measures were there is
the potential to impact biological resources associated with it covered activities. Where such
requirements apply and are relevant, they are noted in the discussion below.
2.0 CEQA REQUIREMENTS
California Code of Regulations (CCR), Title 14 (CEQA Guidelines), Sections 15162 through
15164 discuss a lead or responsible agency’s responsibilities in handling new information that
was not included in a Project’s FEIR. The provisions of Section 15164 apply to the Water
Authority as the responsible agency under CEQA because the proposed modifications to the
Project involve actions that are under the purview of the Water Authority.
Section 15162 of the CEQA Guidelines provides:
(a) When an EIR has been certified…for a project, no subsequent EIR shall be prepared for
that project unless the lead agency determines, on the basis of substantial evidence in
the light of the whole record, one or more of the following:
1. Substantial changes are proposed in the project which will require major
revisions of the previous EIR…due to the involvement of new significant
environmental effects or a substantial increase in the severity of previously
identified significant effects;
2. Substantial changes occur with respect to the circumstances under which the
project is undertaken which will require major revisions of the previous EIR …
due to the involvement of new significant environmental effects or a substantial
increase in the severity of previously identified significant effects; or
3. New information of substantial importance, which was not known and could not
have been known with the exercise of reasonable diligence at the time the
previous EIR was certified as complete…shows any of the following:
(A) The project will have one or more significant effects not discussed in the
previous EIR;
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Second CEQA Addendum 6
(B) Significant effects previously examined will be substantially more severe
than shown in the previous EIR;
(C) Mitigation measures or alternatives previously found not to be feasible
would in fact be feasible and would substantially reduce one or more
significant effects of the project, but the project proponents decline to
adopt the mitigation measure or alternative; or
(D) Mitigation measures or alternatives which are considerably different from
those analyzed in the previous EIR would substantially reduce one or
more significant effects on the environment, but the project proponents
decline to adopt the mitigation measure or alternative.
Alternatively, where some changes or additions are necessary to the previously approved FEIR, but
none of the changes or additions meet the standards as provided for, a subsequent EIR pursuant to
CEQA Guidelines, Section 15162, then the lead or responsible agency is directed to prepare an
addendum to the FEIR. (CEQA Guidelines, Section 15164). Further, the addendum should include
a “brief explanation of the decision not to prepare a subsequent EIR pursuant to Section 15162,”
and that “explanation must be supported by substantial evidence.” (CEQA Guidelines, Section
15164(e)). The addendum need not be circulated for public review, but may simply be attached to
the FEIR (CEQA Guidelines, Section 15164(c)).
This Second Addendum to the FEIR fulfills and conforms to the provisions of CEQA (California
Public Resources Code, Section 21000 et seq.) and the CEQA Guidelines, Section 15164,
providing for the preparation of an addendum. The CEQA Guidelines allow the preparation of an
addendum to an EIR under the following circumstances (14 CCR 15000 et seq.):
1. Only minor technical changes or additions are necessary to make the EIR under
consideration adequate;
2. The changes and additions to the EIR do not raise important new issues about
significant effects on the environment;
3. None of the conditions described in Section 15162, CEQA Guidelines, calling for the
preparation of a subsequent EIR have occurred.
3.0 PROJECT LOCATION AND REGIONAL SETTING
The majority of the proposed Project changes are generally located north of the City of San
Marcos in the Twin Oaks Valley area in northern San Diego County, California (see Figure 1,
Regional Map). Twin Oaks Valley lies between two local coastal mountain ranges: the San
Marcos Mountains to the west and the Merriam Mountains to the east. In addition, and as
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Second CEQA Addendum 7
shown on Figures 1 and 2, several other Project components are located further south in the
City of San Marcos, as well as within the City of Carlsbad.
The TOVWTP is located in an unincorporated area of San Diego County at the northern extent
of Twin Oaks Valley. The approximately 35-acre site has elevations ranging from 1,050 feet
above mean sea level (AMSL) at the northern and eastern boundaries to 1,240 feet AMSL along
the western boundary. The San Marcos Mountains are located immediately west of the
treatment plant. Residential and agricultural uses are to the north, east, and south.
Pipeline 3 of the Second San Diego Aqueduct is immediately adjacent to the TOVWTP and
traverses agricultural, undeveloped land and residential uses, as well as roadways through Twin
Oaks Valley for the first approximately 3.5 miles from the treatment plant south. The remaining 2
miles of pipeline are located within developed areas in the City of San Marcos.
The proposed Aqueduct Connection Point Modifications would be installed at an existing
approximately 1-acre site located at the northwest corner of the intersection of Pawnee and
Cherokee Streets in the City of San Marcos, just southwest of Highway 78. The site is at an
elevation of approximately 575 feet AMSL and slopes gently to the south. Surrounding land
uses include a shopping plaza and vacant land to the south; an auto parts store to the west; a
shopping plaza, some restaurants, and an auto mechanic to the north; and office buildings to
the east.
The Pipeline 4 Vent Replacement and Pipeline Interconnect would be located along Water
Authority Pipeline 4 in an open space area just north of the San Elijo community within the City
of San Marcos.
The Macario Canyon Pipeline Alignment Modification and Pumping Well would be installed in an
open space area in Macario Canyon near the intersection of Cannon Road and Faraday Avenue in
the City of Carlsbad.
4.0 DESCRIPTION OF APPROVED PROJECT
In 2006, the City of Carlsbad approved an amendment to the Precise Development Plan (PDP) for
the EPS to obtain land use approvals to construct and operate an approximately 50 mgd
desalination plant and other appurtenant and ancillary water and support facilities to produce
potable water. The Carlsbad Desalination Plant is to be located on the EPS site, adjacent to the
existing power plant, located immediately south of the Agua Hedionda Lagoon, within the City of
Carlsbad, in northern San Diego County. As approved in 2006, several pipeline routes would
distribute product water from the Carlsbad Desalination Plant to the City of Carlsbad and various
local and regional water agencies, including the Water Authority.
The FEIR analyzed multiple off-site pipeline alignments through portions of Carlsbad, Oceanside,
and Vista. In 2009, Carlsbad approved the First Addendum to document minor modifications to
the desalination plant site layout and the off-site product water pipeline routes. Per the currently
Precise Development Plan and Desalination Plant Project November 2012
Second CEQA Addendum 8
approved project, product water will be delivered into existing Vallecitos Water District (VWD)
pipelines, regulated and metered through an approved Project flow-control facility to be
constructed in the vicinity of Pawnee and Cherokee Streets in the City of San Marcos. The
pipeline crossing Macario Canyon was analyzed as two options in the FEIR: one using trenchless
construction methods north of Cannon Road, and one laying the pipelines within the existing
roadway/bridge. The Coastal Development Permit for the Project went further to indicate that the
pipelines would hang underneath the Cannon Road Bridge in the event that the trenchless option
was not selected.
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FIGURE 1
Regional Map
7250 Second Addendum to the Carlsbad Desalination Plant Project FEIR
015510
Miles
Pipeline 3 Relining
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 Figs\Figure1-Regional.mxdMacario Canyon
Pipeline Alignment
Modification and
Pumping Well Pipeline 4 Vent Replacement
and Pipeline Interconnect
TOVWTP Modifications
Aqueduct Connection
Point Modifications
Precise Development Plan and Desalination Plant Project November 2012
Second CEQA Addendum 10
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FIGURE 2
Vicinity Map
Second Addendum to the Carlsbad Desalination Plant Project FEIR
AERIAL SOURCE: BING Mapping Service
07,0003,500
Feet
TOVWTP
Modifications
Aqueduct Connection
Point Modifications
Pipeline 3
Relining
7250
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 Figs\Figure2-Vicinity.mxdPipeline 4 Vent
Replacement and
Pipeline Interconnect
Macario Canyon
Pipeline Alignment
Modification and
Pumping Well
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Second CEQA Addendum 12
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Precise Development Plan and Desalination Plant Project November 2012
Second CEQA Addendum 13
5.0 DESCRIPTION OF PROPOSED CHANGES TO THE PROJECT
The goal of the proposed Project changes is to enhance access to the desalination conveyance
pipeline for operations and maintenance crews, enhance the pipelines’ functional survivability
and reliability, allow product water to be stored and blended with potable water at the TOVWTP
before distribution, and to allow for greater operational flexibility and efficiency in delivering
product water to the Water Authority’s member agencies. Under these Project modifications,
water from the desalination plant would flow north in Pipeline 3 from the Aqueduct Connection
Point to be constructed at Pawnee and Cherokee Streets. At the TOVWTP, new facilities will
divert flow from Pipeline 3 to existing treated water storage tanks for blending. In addition, the
proposed Project changes include the Pipeline 4 Vent Replacement and Pipeline Interconnect in
San Marcos, and the Macario Canyon Pipeline Alignment Modification and Pumping Well for a
segment of the pipeline along Cannon Road in Carlsbad. Any vegetated areas disturbed during
construction of these proposed Project modifications would be hydroseeded and restored
following disturbance.
The location of all proposed Project modifications is shown on Figures 1 and 2. More
specifically, the proposed Project changes entail the following improvements:
Twin Oaks Valley Water Treatment Plant (TOVWTP) Modifications: Minor
modifications to the treatment plant would include:
o A new valve vault structure on Pipeline 3 to divert flows to the TOVWTP storage
tanks
o A new approximately 1,000-foot-long, 54-inch-diameter pipeline that would connect
Pipeline 3 to the existing pipeline inlets of two treated water storage tanks
o A chemical injection and monitoring station and pump well associated with the
new 54-inch-diameter pipeline
o A third flow-control facility with a 42-inch-diameter pipeline that would be located
adjacent to the two existing treated water-flow control facilities (see Figure 3,
TOVWTP Modifications).
All construction associated with the proposed 54-inch pipeline connection from Pipeline
3 to the treated water tanks would occur entirely within a Water Authority right-of-way
(ROW) and the Water Authority-owned TOVWTP site. Specifically, 700 feet of the
proposed pipeline is located on the treatment plant site, and the remaining 300 feet is
within ROW that includes an existing road that connects from El Paso Alto Road to the
treatment plant. Construction at the TOVWTP would be phased over a period of
approximately 7 months, and is anticipated to begin in August 2013. The first phase of
construction would consist of establishing connections to the existing pipeline and plant
piping at a time when water treatment plant production is low. Construction during this
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Second CEQA Addendum 14
phase would include excavation, grading and filling, and welding. The second phase of
construction would consist of installing the new 54-inch pipeline and installing a third
flow-control facility (and associated pipeline) parallel to the existing two flow-control
facilities. Construction during this phase would include excavation, grading, filling and
welding, and pouring concrete, and would use the following equipment: two excavators,
a backhoe, articulated trucks, a dozer, two loaders, a water truck, a compactor, an air
compressor, pick-up trucks, a boom truck, a hydro crane, hand compactors, welding
machines, and a job trailer. Construction equipment would access the TOVWTP via
Twin Oaks Valley Road and local roads previously used for construction of TOVWTP.
Construction staging would occur within the grounds of the treatment plant.
Pipeline 3 Relining: Pipeline 3 currently operates as a gravity-flow system from north to
south. Under the proposed operating scenario, the pipeline would be operated as a
pressurized pipeline with flow from south to north. To safely and reliably operate the pipeline
in this scenario, the existing 5.5-mile-long Pipeline 3 segment between the Aqueduct
Connection Point and the TOVWTP will be relined. This segment of Pipeline 3 is in need of
relining even without the proposed Project modifications, and would need to be relined
within the next 12 years to remain in service. It is assumed for the purposes of this analysis
that approximately 500 linear feet of Pipeline 3 will need replacing rather than relining.
Pipeline 3 would be accessed via 15 portals located approximately 2,000 feet apart along
the pipeline (see Figure 4, Pipeline Relining Portal Locations). The 85-foot by 20-foot
excavated portals would be used to pull the pipe liner from high points along the pipeline that
are generally associated with air vacuum/blow-off locations. Staging areas are anticipated to
be approximately 300 feet by 100 feet, or approximately 0.69 acre in size.
Construction activities associated with the relining of Pipeline 3 would include the
following phases:
o Portal Development
Duration and activities: 2 days at each portal to install fencing, as well as
to install piles for shoring
Equipment used: two excavators, crane, loader/forklift
o Portal Excavation
Duration and activities: 3 days at each portal to install steel shoring plates
and excavate portal
Equipment used: Excavator, loader, dump truck, water truck
o Existing Pipe Demolition
Duration and activities: 3 days at each portal to cut and remove existing
pipeline
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Second CEQA Addendum 15
Equipment used: Excavator, loader, air compressor, two welding rigs,
dump truck
o Steel Liner Installation
Duration and activities: 24 days at each portal to place and weld steel liners
Equipment used: Crane, two welding rigs, excavator
o Grouting
Duration and activities: 10 days at each portal to grout annular spacing
between new steel liner and existing concrete pipe
Equipment used: Grouting pump
o Interior Mortar Lining
Duration and activities: 10 days to install mortar lining
Equipment used: Spin lining machine, blower/fan
o Portal Closure
Duration and activities: 14 days at each portal to install new welded steel
pipe, install reinforcing steel, pour concrete, and backfill
Equipment used: Crane, two welding rigs, excavator, concrete, truck,
water truck
o Site Restoration.
Aqueduct Connection Point Modifications: The proposed modifications to the Water
Authority’s Aqueduct Connection Point in San Marcos to enable northward flow would
include installation of valves in Pipelines 3 and 4, a flow meter, and appurtenant piping
(see Figure 5, Aqueduct Connection Point Modifications). Construction would take place
within the approved construction footprint for the VWD Flow-Control Facility, involving
the same area of disturbance, construction time frame, and similar construction
techniques to those previously evaluated in the First Addendum (City of Carlsbad 2009).
As indicated in the First Addendum, the structures at this location were previously
considered with the construction of the off-site product water pipelines in the FEIR (City
of Carlsbad 2009).
In very rare circumstances, water from the Carlsbad Desalination Project may be directly
delivered south in the Water Authority’s aqueduct. If needed in these instances to
assure acceptable water quality, a chemical injection facility will be installed at the San
Marcos connection point to treat the product water prior to introduction into the Water
Authority’s aqueduct. These facilities would only be used when the water is routed to the
south rather than north to the TOVWTP. This is not a normal operation mode and would
only be required in rare circumstances where Pipeline 3 or Pipeline 4 are out of service
upstream of the desalination connection facilities. This chemical injection facility would
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Second CEQA Addendum 16
consist of two 5,000 gallon tanker trucks temporarily parked within secondary
containment structures. One truck would contain sodium hypochlorite (11%–14%
solution) and one truck would contain aqueous ammonia (17%–20% solution). The
sodium hypochlorite would be injected into the product water at a rate of 700 gal/day.
The ammonia would be injected at a rate of 350 gal/day. Approximately one sodium
hypochlorite truck delivery per week and one aqueous ammonia truck delivery every 2
weeks would be required during periods when chemical injection is in use.
Pipeline 4 Vent Replacement and Pipeline Interconnect: The existing vent along
Pipeline 4 in San Marcos would be removed and replaced with a new vent structure to
allow for an increase in the upstream pressure (hydraulic gradient) in Pipeline 4, which is
required to divert water from Pipeline 4 to Pipeline 3 downstream of the San Marcos
connection facilities. A new 40-foot-long, 54-inch-diameter, above grade pipeline to
connect Pipeline 3 to Pipeline 4 would be located directly upstream and adjacent to the
proposed new vent. The new vent would be located on the same site of the existing vent
that is located approximately 250 feet west of Schoolhouse Way, and approximately
0.85 mile north of the center of the Community of San Elijo Hills within the City of San
Marcos, California (Figure 2). Construction of the new vent would utilize an
approximately 1.4-acre temporary work area. A smaller 0.06-acre temporary work area
would also be needed (see Figure 6a, Pipeline 4 Vent Replacement and Pipeline
Interconnect). A concrete weir vent would be constructed that would extend above grade
by approximately 20 feet and cover an approximately 12- by 25-foot area. The top of the
weir vent would include a ventilation screen and hatches. The remaining vent
mechanisms would either be located inside the weir vent or would be below grade (see
Figure 6b, Pipeline 4 Vent Replacement and Pipeline Interconnect Plan and Cross-
Section). The existing 19-foot tall vent stack would be removed and capped near ground
level.
Construction of the Pipeline 4 Vent Replacement would take place over an approximately
7-month period and consist of two phases: excavation and construction. Activities in the
work area would include access improvements for construction equipment; blasting (the
new vent is located in an area where there is exposed hard rock); excavation, hauling, and
stocking of excavated materials; pipe demolition; concrete cutting; material and equipment
delivery and storage; reinforced concrete placement; pipe installation; grading; fence
installation; and hydroseeding. Access to the site would be via existing Water Authority dirt
roads in the Project area that are accessed via Schoolhouse Way to the south or from La
Plaza Drive to the north. The first phase of construction would consist of excavation, would
take approximately 3 months to complete and would include use of the following
equipment: one hydraulic drill rig, one excavator, one dozer, dump trucks, a water truck,
and a blower. The second phase would include construction of the new vent, would take
approximately 4 months to complete, and would involve use of the following construction
equipment: one concrete pump truck, concrete delivery trucks, flatbed delivery trucks, one
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Second CEQA Addendum 17
30-ton rubber tire crane, one excavator, one loader, and a blower. Construction staging
would occur within areas shown on Figure 6a.
Macario Canyon Pipeline Alignment Modification and Pumping Well: The Macario
Canyon Pipeline Alignment Modification involves 1,640 feet of trenchless pipe
installation crossing Macario Canyon. The FEIR analyzed this segment of pipeline under
two scenarios: open trenching within Cannon Road and trenchless construction just
north of Cannon Road across Macario Canyon. Since the installation of this portion of
the Faraday Avenue pipeline route was included in the FEIR using trenchless
construction, no further analysis of the underground pipeline installation beneath
Macario Canyon is required under CEQA. The minor change in alignment (shifted to
south of Cannon Road between Cannon and Faraday – see Figures 7a and 7b) and
similar construction techniques across sensitive wetland areas would not represent a
substantial change in the Project or its effects. The modifications shift the location of the
pipeline in this area approximately 1,000 feet to the south and add a pumping well to be
installed along the pipeline alignment to allow for maintenance of the pipeline.
Construction of this realigned portion of the pipeline would use traditional directional
drilling techniques. Due to the topography, which creates a low point in the pipeline, the
pipeline in this area would include a pumping well and a drain line (above the pipeline)
that connects to a storm drain on Faraday Avenue (Figures 7a and 7b) to allow for
drainage of the pipe. The pumping well would be installed approximately mid-way along
the pipeline alignment between Cannon Road and Faraday Avenue. The pumping well
would be consistent with other Water Authority pumping wells and would be used during
infrequent events when the pipeline may need to be taken off-line for maintenance
and/or repair. The aboveground physical dimensions of the pumping well are anticipated
to consist of an approximately 48-inch-diameter manhole that would be raised
approximately 6 inches above ground level.
Construction of the pipeline and pumping well would occur within portions of Cannon
Road and Faraday Avenue, as well as within an open space area in Macario Canyon.
During construction, the Water Authority would establish an 80-foot-wide temporary work
easement in Macario Canyon. The pipeline would be installed in two segments via
directional drilling from a construction site located approximately 1,200 feet south of the
intersection of Cannon Road and Faraday Avenue and shown on Figure 7a. There
would be two receiving pits—one in Cannon Road and one in Faraday Avenue. Impacts
to sensitive habitats would be avoided. Access to the site would be via Cannon Road,
Faraday Avenue, and existing dirt access roads that extend from Cannon Road to the
construction area and pumping well site as shown on Figure 7a. Construction of the
pipeline would take approximately 9 months, is anticipated to begin in May 2014, and
would require the use of an excavator, mobile crane, front end loader, water truck,
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Second CEQA Addendum 18
boring machine, and bull dozer. During boring, work trucks would enter the site daily to
haul away spoils and deliver pipe.
6.0 SAN DIEGO COUNTY WATER AUTHORITY ACTIONS
To process the proposed changes, the following Water Authority actions are required:
1. EIR 03-05(B) – Second Addendum to the Project’s certified EIR; as a responsible agency
under CEQA, the Water Authority will be accepting the City of Carlsbad’s previously
approved FEIR and First Addendum, as well as approving this document, the Second
Addendum
2. Approval of various agreements to purchase water and construct facilities.
7.0 IDENTIFICATION OF ENVIRONMENTAL EFFECTS
Documents containing the environmental analysis supporting the City of Carlsbad’s action in
approving the Project include the FEIR, First Addendum, Mitigation Monitoring and Reporting
Program, CEQA Findings, and additional responses provided for comments submitted after
publication of the FEIR.
The Second Addendum analyzes all 11 environmental issue areas that were included in the
FEIR and First Addendum, and discusses whether the proposed Project modifications described
in Section 5.0 would trigger significance criteria identified in the CEQA Guidelines, Section
15162, in each of these areas. For each environmental issue area, a comparative analysis of
the impacts presented in the FEIR and First Addendum to the FEIR is provided. The analysis
includes a determination regarding the occurrence of any new significant impacts or an increase
in the severity of previously identified impacts. Finally, an analysis is presented to determine
whether there are any changed circumstances or new information relative to the revised Project.
Existing 90" Pipeline
New 90° Bend, typ.
Existing Flow
Control Facility
75" Existing Pipeline 3New 54" Pipeline
Expand Flow Control Facility
EXISTING STORAGE TANK NO. 2
New Vent, typ.
Connect to Existing 72"Pipe, Reduce to 54"
10" Air Relief / AirVacuum Valve
To Existing Weir Structure
New Pump Well
New 42" Pipeline
Connect to Existing
90" Pipeline
Connect to Existing 84"Pipeline
New Chemical Injectionand Monitoring Station
EXISTING STORAGE TANK NO. 1
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 FigsSecond Addendum to the Carlsbad Desalination Plant Project FEIR
7250
SOURCE: GHD 2010
TOVWTP ModificationsFIGURE 3
NOT TO SCALE
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Second CEQA Addendum 20
INTENTIONALLY LEFT BLANK
PORTAL 15
PORTAL 14
PORTAL 13
PORTAL 11
PORTAL 10
PORTAL 9
PORTAL 8
PORTAL 7
PORTAL 6
PORTAL 5
PORTAL 4
PORTAL 3
PORTAL 2
PORTAL 1
PORTAL 12
Portal and Staging Area Location
CWA Right-of-Way
FIGURE 4
Pipeline 3 Relining Portal Locations
Second Addendum to the Carlsbad Desalination Plant Project FEIR7250
AERIAL SOURCE: BING MAPPING SERVICE
02,0001,000 Feet
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Second CEQA Addendum 22
INTENTIONALLY LEFT BLANK
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 FigsSecond Addendum to the Carlsbad Desalination Plant Project FEIR
7250
SOURCE: JACOBS 2012
Aqueduct Connection Point Modifications
FIGURE 5
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Second CEQA Addendum 24
INTENTIONALLY LEFT BLANK
FIGURE 6a
Pipeline 4 Vent Replacement and Pipeline Interconnect
Second Addendum to the Carlsbad Desalination Plant Project FEIR7250
AERIAL SOURCE: BING MAPPING SERVICES
0260130
Feet
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 Figs\Pipeline 4 Vent Replacement
Existing Pipeline 4 Alignment
Temporary Work Area
CWA Right-of-Way
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Second CEQA Addendum 26
INTENTIONALLY LEFT BLANK
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 FigsSecond Addendum to the Carlsbad Desalination Plant Project FEIR
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SOURCE: SDCWA 2012
Pipeline 4 Vent Replacement and Pipeline Interconnect Plan and Cross Section
FIGURE 6b
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Second CEQA Addendum 28
INTENTIONALLY LEFT BLANK
FIGURE 7a
Macario Canyon Pipeline Alignment Modification and Pumping Well
Second Addendum to the Carlsbad Desalination Plant Project FEIR
AERIAL SOURCE: BING MAPPING SERVICE
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 Figs\7250
0300150Feet
Directional Drilling for Waterline Alignment
Macario Canyon Pumping Well
Temporary Work Area
Receiving Pit Location
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Second CEQA Addendum 30
INTENTIONALLY LEFT BLANK
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 FigsSecond Addendum to the Carlsbad Desalination Plant Project FEIR7250
SOURCE: SDCWA 2012
Macario Canyon Pipeline Alignment Modification and Pumping Well Cross SectionFIGURE 7b
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INTENTIONALLY LEFT BLANK
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Second CEQA Addendum 33
8.0 ANALYSIS
The following environmental analysis supports the Water Authority’s determination that approval
and implementation of the proposed Project modifications would not result in any new significant
environmental impacts or a substantial increase in the severity of previously disclosed impacts
covered under the FEIR and First Addendum. This environmental analysis is subject to all
applicable mitigation measures outlined in the FEIR and Mitigation Monitoring and Reporting
Program. In addition, the Water Authority’s General Conditions and Standard Specifications
(2005 edition) have been considered in this environmental analysis, and will also be
incorporated into the construction plans and specifications, as appropriate. The Water Authority
updates the General Conditions and Standard Specifications periodically to reflect changes in
law, advancement of construction methods, materials, and standards, and other issues as
deemed appropriate for the Water Authority to achieve its mission.
As stated in Section 1.0, activities associated with the proposed modifications are subject to the
requirements and mitigation measures identified in the FEIR, and First Addendum, and the
NCCP/HCP EIR/EIS and associated NCCP/HCP and implementing agreement. Where such
requirements apply and are relevant, they are noted in the discussion below.
The FEIR and First Addendum, the NCCP/HCP EIR/EIS, and the Water Authority’s General
Conditions and Standard Specifications are on file at the Water Authority’s office, 4677
Overland Avenue, San Diego, California, 92123,
The following presents the environmental analysis of impacts associated with the proposed
Project modifications. In instances where the impacts resulting from several Project components
would be similar, their corresponding analyses have been grouped together. In instances where
impacts differ by Project component, they are discussed separately.
Aesthetics
Analysis of aesthetic impacts and EIR-identified mitigation measures of the approved Project
are contained in the FEIR, Section 4.1, pages 4.1-3 through 4.1-12. See also CEQA Findings,
pages 10 and 11.
The Carlsbad Desalination FEIR and First Addendum concluded that because aesthetic impacts
from construction activities would be short-term and within limited areas, construction-related
impacts to visual resources would be considered less than significant. Similarly, the construction
activities associated with the proposed Project modifications would also be temporary and within
limited areas and, therefore, would also result in less-than-significant impacts to
aesthetics/visual resources.
Analysis of the Revised Project
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Second CEQA Addendum 34
TOVWTP Modifications
The proposed modifications to the TOVWTP are evaluated utilizing the same criteria discussed in
the Carlsbad FEIR (Section 4.1). Specifically, construction of the TOVWTP modifications will cause
short-term, temporary aesthetic impacts, including equipment storage, materials, soil stockpiling and
debris exposed to public views. Because these impacts are short-term in nature, and because they
affect a limited area already containing similar structures, they are not considered to have a
substantial adverse effect on a scenic vista, nor would they substantially damage scenic resources.
Likewise, the long-term impacts of these additional facilities are less than significant because the
new facilities will be designed with the same aesthetic character as the existing on-site water control
and treatment facilities. All new pipelines would either be buried or screened. The third flow-control
facility would be located directly adjacent to the existing flow-control facility, and would be designed
with the same aesthetic character as the existing facility. These minor modifications to the TOVWTP
would not substantially alter the views of the treatment plant facilities. Therefore, the inclusion of
these facilities would not result in new impacts or increase the severity of impacts identified in the
Carlsbad FEIR, and therefore would not change the FEIR conclusions that the impacts are less
than significant.
Pipeline 3 Relining
As discussed in the Carlsbad FEIR and First Addendum, since pipelines are underground, no
long-term impacts to aesthetics would occur from pipeline installation. Therefore, the inclusion
of the Pipeline 3 Relining effort would not result in new significant impacts or increase the
severity of impacts identified in the FEIR, and therefore would not change the FEIR conclusion.
Aqueduct Connection Point Modifications
Similar to the conclusion reached in the Carlsbad FEIR regarding the temporary nature of
construction activities for the pipelines and adjunct facilities, temporarily parking two 5,000-
gallon chemical tanker trucks at the aqueduct connection point, an existing disturbed/developed
area, would not result in new aesthetic impacts, nor increase the severity of impacts identified in
the FEIR. They would not constitute a permanent visual impact, and would only be present in
very rare circumstances when water from the Carlsbad Desalination Project needs to be
delivered directly south, such as when Pipeline 3 or Pipeline 4 are out of service. Additionally,
the tanker trucks would be parked in an industrial area, and would be consistent with the
surrounding land uses. The inclusion of these chemical tanker trucks in rare circumstances
would not result in new impacts or increase the severity of impacts identified in the FEIR, and
therefore would not change the FEIR conclusion.
Pipeline 4 Vent Replacement and Pipeline Interconnect
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Second CEQA Addendum 35
As mentioned earlier, the Pipeline 4 Vent Replacement and Pipeline Interconnect would include a
12-foot by 25-foot weir vent that would extend approximately 20 feet above grade, and a 40-foot
length of 54-inch diameter pipeline to interconnect Pipelines 3 and 4. The interconnect pipeline
would be approximately six feet above grade. The existing vent is at approximately 1,020 feet
AMSL and extends approximately 19 feet above grade. Due to the natural topography of the area,
the existing and proposed vent location, and proposed interconnection pipeline location is visible
from a limited number of homes located on nearby ridgelines approximately 1/3 of a mile south
and southwest of the site in the San Elijo Hills community. Considering low profile of the
interconnect pipeline and that the the existing vent is similarly visible from existing vantage points
of the vent location, the inclusion of the vent replacement and pipeline interconnect would not
result in new significant impacts or increase the severity of impacts identified in the FEIR, and
therefore would not change the FEIR conclusion.
Macario Canyon Pipeline Alignment Modification and Pumping Well
Other than the temporary nature of construction-related visual impacts discussed above, and a
manhole cover, no other visual impacts will occur as a result of the Macario Canyon Pipeline
Alignment Modification and Pumping Well changes. The pumping well would impact a limited
area and would not consist of any above-grade structures other than a manhole. The manhole
would be visible from a very limited number of vantage points due to its size and the natural
topography of the area. Therefore, the inclusion of the pumping well would not result in new
impacts or increase the severity of impacts identified in the FEIR, and therefore would not
change the FEIR conclusion.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no changes with respect to circumstances under which the Project would be
undertaken, and there is no new information of substantial importance that has become
available relative to visual or aesthetic resources. No substantial changes in the aesthetic or
visual environment have occurred since certification of the FEIR, and no substantial new
sensitive receptors or scenic resources have been identified within the vicinity of the proposed
Project modifications.
Conclusion
Based on the above, no new significant aesthetic impacts or a substantial increase in previously
identified aesthetic impacts would occur as a result of the proposed modifications. All mitigation
measures previously adopted for the approved Project will apply to the proposed Project described
herein, as applicable. Therefore, the impacts to aesthetic resources and the proposed Project
modifications do not meet the standards for a subsequent or supplemental EIR as provided
pursuant to CEQA Guidelines, Section 15162.
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Second CEQA Addendum 36
Air Quality
Analysis of air quality impacts of the approved Project are contained in the FEIR, Section 4.2,
pages 4.2-10 through 4.2-21. See also CEQA Findings, page 11.
The Carlsbad Desalination FEIR and First Addendum concluded that impacts to air quality as a
result of construction and operation of the approved Project were less than significant. The FEIR
had originally assumed that seven segments of 1,000 feet of pipeline would be constructed
simultaneously. Emission calculations were based on two crews placing base material, four
crews laying the pipeline in the trench, and three crews backfilling the trench at any given time.
Analysis of the Revised Project
Construction of the proposed Project modifications would result in temporary increases in
criteria pollutant emissions associated with construction equipment. While the FEIR had
assumed that seven segments of 1,000 feet of pipeline would be constructed at any given time,
under the new construction schedule there would be no more than two segments of 1,000 feet
of pipeline constructed simultaneously. As a result, the disclosed construction emissions in the
FEIR associated with the off-site pipelines are substantially overestimated when the revised
construction scenario is considered, and it has been determined that the construction activities
associated with the proposed Project modifications—in combination with the construction
activities associated with pipeline construction—would not exceed the emissions previously
disclosed in the FEIR for any criteria pollutant. Similar to the findings of the FEIR and First
Addendum, the construction-related air pollution emissions from the proposed Project
modifications would be temporary and would not be expected to have a permanent significant
impact on ambient air quality.
The Project modifications do not propose any changes to the operational characteristics of the
desalination plant; therefore, there are no potential increased direct or indirect emissions
associated with operation of the desalination plant that were not discussed in the Carlsbad
FEIR.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
As discussed in the First Addendum to the FEIR, Assembly Bill 32 (AB 32)requires the
California Air Resources Board (CARB), the state agency charged with regulating statewide air
quality, to adopt rules and regulations that would achieve greenhouse gas (GHG) emissions
equivalent to statewide levels in 1990 by 2020. GHG emissions were addressed in the First
Addendum in 2009 through the California Coastal Commission’s conditional approval of the
Project’s Energy Minimization and Greenhouse Gas Reduction Plan (GHG Plan). The GHG
Plan provides for the assessment, reduction, and mitigation of GHG emissions, and establishes
Precise Development Plan and Desalination Plant Project November 2012
Second CEQA Addendum 37
a protocol for identifying, securing, monitoring, and updating measures to eliminate the Project’s
net carbon footprint. Once the Project is operational and all measures to reduce energy use at
the site have been taken, the protocol involves the following steps, completed each year:
1. Determine the energy consumed by the Project for the previous year
2. Determine San Diego Gas and Electric (SDG&E) emission factor for delivered electricity
from its most recently published Annual Emissions Report
3. Calculate the Project’s gross indirect GHG emissions resulting from Project operations
by multiplying its electricity use by the emission factor
4. Calculate the Project’s net indirect GHG emissions by subtracting emissions avoided as
a result of the Project (Avoided Emissions) and any existing offset projects and/or
Renewable Energy Credits (RECs)
5. If necessary, purchase carbon offsets or RECs (or pay an in-lieu fee) to zero-out the
Project’s net indirect GHG emissions.
The following are elements of the plan, based on a draft “Greenhouse Gas Emissions Template”
provided by the California Coastal Commission:
A. Increased Energy Efficiency (such as use of a pressure-exchanger energy recovery system
that captures energy from the discharge stream and high-energy efficiency pumps)
B. GHG Emission Reduction by Green Building Design
C. On-Site Solar Power Generation
D. Recovery of CO2 (carbon dioxide in a gaseous form will be added to the reverse osmosis
permeate in combination with calcium hydroxide or calcium carbonate in order to form
soluble calcium bicarbonate which adds hardness and alkalinity to the drinking water for
distribution system corrosion protection)
E. Avoided Emissions from Reducing Energy Needs for Water Reclamation (reduced
salinity of source water would reduce the need to remove salts from wastewater to meet
recycled water requirements)
F. Avoided Emissions from Displaced Imported Water
G. Avoided Emissions through Coastal Wetlands (carbon sequestration).
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Second CEQA Addendum 38
All energy use required to deliver product water would be incurred by pumps at the Carlsbad
Desalination Plant, and this energy use was previously analyzed in the FEIR for the Carlsbad
Desalination Plant Project. GHG emissions from construction activities associated with the
proposed Project modifications would not exceed those identified in the FEIR, and 25,000 tons
of carbon offsets as mitigation for construction-related emissions from the construction of the
desalination plant will be purchased, which far exceeds the offsets that would actually be
needed for construction-related impacts, even with the addition of these modifications.
The proposed Project modifications would not result in an increase in overall GHG emissions. The
Project’s GHG Plan was approved by the California Coastal Commission in August 2008. With
implementation of the GHG Plan, the Project will demonstrate a “net zero” impact on GHG
emissions from indirect sources (electrical energy consumption). The Project as revised would,
therefore, not increase the severity of previously identified air quality impacts, nor would it result in
any new significant effects related to air pollutant emissions that were not previously identified.
Conclusion
The proposed Project modifications are consistent with the GHG Plan requirement
demonstrating a “net zero” impact on GHG emissions from indirect sources (electrical energy
consumption). The proposed Project as revised would not increase the severity of previously
identified air quality impacts, nor would it result in any new significant effects related to air
emissions that were not previously identified in the FEIR. Additionally, in light of the wide
range of global warming activity prior to the certification of the FEIR in June 2006, there are
no substantial changes to the circumstances under which the Project will be undertaken, and
no new information of substantial importance which was not known and could not have been
known when the FEIR was certified has since been identified. Therefore, the impacts to air
quality and the proposed Project modifications do not meet the standards for a subsequent or
supplemental EIR as provided pursuant to CEQA Guidelines, Section 15162.
Biological Resources
Analysis of biological resources impacts and EIR-identified mitigation measures of the approved
Project are contained in the FEIR, Section 4.3, pages 4.3-18 through 4.3-54. See also CEQA
Findings, pages 12 through 14. The proposed Project modifications are considered to be
covered under this analysis with the exception of the TOVWTP Modifications and Aqueduct
Connection Modifications, Pipeline 3 Relining, and Pipeline 4 Vent Replacement and Pipeline
Interconnect.
In addition to the analysis provided in the Carlsbad EIR and First Addendum, the Water
Authority also has the benefit of the approved NCCP/HCP, its implementing agreement, and
existing federal Endangered Species Act Section 10(a)(1)(B) incidental take permit and
California Fish and Game Code Section 2835 take permit. The NCCP/HCP Final EIR/EIS
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Second CEQA Addendum 39
(Section 4 and appendices) contains a thorough analysis of biological resources impacts and
associated project design features and mitigation measures associated with Covered Activities
including minor modifications to existing Water Authority facilities. This analysis and the
associated mitigation measures described therein will apply to the proposed modifications
associated with the TOVWTP modifications, Pipeline 3 Relining, and the Pipeline 4 Vent
Replacement and Pipeline Interconnect.
Analysis of the Revised Project
TOVWTP Modifications and Aqueduct Connection Point Modifications
The modifications to the TOVWTP associated with the proposed Project will not result in new
significant impacts to Biological Resources. Proposed modifications to the TOVWTP and at the
connection point to Pipeline 3 would be within previously developed areas. No direct biological
impacts would occur at these sites. Indirect impacts from construction and operation of the
proposed treatment plant modifications may include noise, fugitive dust, erosion and
sedimentation. Disturbed areas will be restored per Section 6.6.2 of the NCCP/HCP.
Additionally, mitigation for indirect impacts will occur pursuant to the NCCP/HCP. Lastly,
impacts would also be reduced through incorporation of the Water Authority’s General
Conditions and Standard Specifications/Project Design Features discussed Biological
Resources Technical Report for the Pipeline 3 Relining and Associated Improvements Project
(Dudek 2012). Therefore, the TOVWTP modifications would not result in new impacts or
increase the severity of impacts identified in the NCCP/HCP EIR/EIS, and therefore would not
change the NCCP/HCP EIR/EIS conclusion. Therefore, no new significant impacts or
substantially more severe impacts would occur during construction at the treatment plant with
the proposed modifications.
Pipeline 3 Relining
In 2010, the Water Authority approved the Final EIR/EIS for the Water Authority Subregional
NCCP/HCP (Water Authority 2010a, 2010b). The NCCP/HCP addresses the potential impacts
of Water Authority activities on special-status biological resources. These activities include new
construction and typical expansion of existing infrastructure, and ongoing installation, use
maintenance, and repair of aqueduct and water conveyance, treatment, and storage systems.
Impacts to 63 special-status species are covered under the NCCP/HCP through avoidance and
minimization requirements, as well as approximately 704 acres of Water Authority mitigation
credits (Water Authority et. al. 2010). Relining of Pipeline 3 is a covered activity in the
NCCP/HCP. No new impacts would occur due to the proposed Project modifications that were
not previously considered in the NCCP/HCP EIR/EIS. As covered activities under the
NCCP/HCP, the biological impacts from these activities have been addressed and will be
mitigated with implementation of the applicable mitigation measures in the NCCP/HCP Section
6 and Appendix B (Water Authority. 2010b).
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Second CEQA Addendum 40
The Biological Resources Technical Report for the Pipeline 3 Relining and Associated
Improvements Project (Dudek 2012) contains a Project-level analysis of biological impacts
resulting from the proposed Project modifications. The findings of that analysis are included
below.
Implementation of the Pipeline 3 Relining would result in direct impacts to 3.71 acres of native
vegetation that would require mitigation pursuant to the NCCP/HCP, including 3.66 acres of
vegetation within the Water Authority ROW and 0.05 acre of vegetation outside the ROW and
inside of Biologically Significant Resource Areas (BSRA). The mitigation program for impacts
would include using 0.325 acre of mitigation credits within the Crestridge Habitat Management
Area (HMA) or San Miguel Conservation Bank, and restoration of impacts per NCCP/HCP
Section 6.6.2. Both mitigation sites are identified as BSRAs under the NCCP/HCP.
Although two sensitive plants and four sensitive wildlife species were observed in the Study
Area and others have a moderate potential to occur, the Project has been designed to avoid
direct impacts to these species and will apply the Special Conditions for avoidance and
minimization pursuant to the NCCP/HCP to reduce potential impacts to a level below significant.
No significant direct impacts are proposed or anticipated to any sensitive plant or wildlife
species or U.S. Fish and Wildlife Service (USFWS)-designated critical habitat for any special-
status species. Portal 13 is located adjacent to critical habitat designated for thread-leaved
brodiaea (Brodiaea filifolia); however, this area consists of ornamental vegetation and a paved
access path located between rows of a residential subdivision and supports no primary
constituent habitat elements required for the species. Further, focused surveys for rare plants
were negative in this area and the Portal 13 impact area has been designed to avoid the thread-
leaved brodiaea critical habitat mapped at this location.
Disturbance of vegetation communities could affect native nesting birds if Project activities occur
during the nesting season. Pursuant to the NCCP/HCP, the nesting season is defined as
January 15 to July 31 for raptor species, March 15 to September 15 for riparian species, and
February 15 to August 15 for upland species. Compliance with the federal Migratory Bird Treaty
Act (MBTA) and Fish and Game Code Sections 3503.5 and 3513 will be ensured either by
removing/modifying potential nesting habitat outside the nesting season, or by having a qualified
Environmental Surveyor conduct pre-activity nest surveys to determine the status of nesting
birds within and around the impact areas if any vegetation disturbance occurs during the nesting
season. If an active nest is detected and construction must proceed, the Environmental
Surveyor will establish buffer guidelines (typically 100-foot buffer zone) and nest activity will be
monitored to ensure compliance with the MBTA and Fish and Game Code.
The Project also has been designed to ensure that potential indirect impacts associated with
drainage/water quality, lighting, increased human activities during Project construction, and
invasive species would be less than significant. Potentially significant indirect impacts to
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Second CEQA Addendum 41
nesting/breeding least Bell’s vireo (Vireo bellii pusillus) (if present) due to construction noise
could result from implementation of the proposed Project. Implementation of species-specific
NCCP/HCP special conditions would ensure that these impacts remain less than significant.
In addition to the incorporation of mitigation measures from the NCCP/HCP, impacts to
biological resources resulting from the Pipeline 3 Relining effort would also be reduced through
incorporation of the Water Authority’s General Conditions and Standard Specifications, as
outlined in the Biological Resources Technical Report (Dudek 2012). Therefore, the Pipeline 3
relining would not result in new impacts or increase the severity of impacts identified in the
NCCP/HCP EIR/EIS, and therefore would not change the NCCP/HCP EIR/EIS conclusion.
Pipeline 4 Vent Replacement and Pipeline Interconnect
Similar to the Pipeline 3 relining, the Pipeline 4 vent replacement and pipeline interconnect
would be a covered activity under the NCCP/HCP. Construction activities at this site would
result in approximately 0.62 acre of impact to coastal sage scrub. Mitigation requirements for
permanent impacts will be fulfilled using the Crestridge HMA or San Miguel Conservation Bank
in accordance with the NCCP/HCP, as well as restoration on site. Disturbed areas will be
restored per Section 6.6.2 of the NCCP/HCP. Additionally, mitigation for indirect impacts will
occur pursuant to the NCCP/HCP. Lastly, impacts would also be reduced through incorporation
of the Water Authority’s General Conditions and Standard Specifications. Therefore, the
Pipeline 4 Vent Replacement and Pipeline Interconnect would not result in new impacts or
increase the severity of impacts identified in the NCCP/HCP EIR/EIS, and therefore would not
change the NCCP/HCP EIR/EIS conclusion.
Macario Canyon Pipeline Alignment Modification and Pumping Well
Implementation of the proposed Project modifications would result in temporary impacts to 0.14
acre of non-native annual grassland at the proposed drilling portal location and construction
staging area, which are within the temporary work area shown on Figure 7a. The project would
also result in 13 square feet of permanent impacts resulting from the placement of the 48-inch-
diameter manhole within the non-native annual grassland habitat. Impacts were calculated by
overlaying the portal, staging area, and blow-off valve structure locations over a vegetation map.
All work will be contained within this temporary work area footprint, which also includes
approximately 0.04 acre of developed area. Impacts on developed land are regarded as less
than significant. No impacts to wetlands or jurisdictional waters would occur, and all construction
activities would occur at least 100 feet away from wetland habitats. The direct impacts to annual
grassland are within the scope of the impacts analyzed in the FEIR and the First Addendum. As
noted previously, the FEIR addressed a broad scope of impacts on sensitive biological
resources to provide for flexibility in final design and alignment of the conveyance pipelines. As
a result, impacts reported in the FEIR are greater than what would occur with the proposed
Project modifications. Specifically, previously addressed impacts from the Final EIR were
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Second CEQA Addendum 42
avoided with the alignment and design changes addressed in the First Addendum, as described
in more detail below. Thus, the approved Project under the First Addendum would have resulted
in reduced impacts to sensitive communities as compared to the impacts that were identified in
the FEIR.
Among these impacts addressed in the FEIR were 3.71 acres of impact to annual grassland.
The 3.71 acres of impact to annual grassland were mapped along the potential pipeline
segments located just north of Palomar Airport and in the Shadowridge area. Since the impacts
to annual grassland that would occur as a result of the currently proposed Project modifications
in Macario Canyon would be less than the total acres anticipated to be impacted under the
FEIR, the impacts associated with the Project modification in Macario Canyon are within the
scope of the analysis of the FEIR. With implementation of FEIR Mitigation Measure 4.3-1,
impacts to 0.14 acre of annual grassland in Macario Canyon are considered less than
significant.
Construction activities in Macario Canyon would also result in indirect impacts to adjacent sensitive
habitats and wildlife, including potential impacts from construction-generated dust, siltation, and
noise. Implementation of FEIR Mitigation Measures 4.3-3, 4.3-4, and 4.3-5 would ensure that
impacts remain below a level of significance. Consistent with the FEIR, with implementation of
mitigation, indirect impacts from construction activities would be considered less than significant.
Based on the above analysis, the modifications to the pipeline in Macario Canyon would not
result in impacts that were not previously identified and mitigated per the FEIR. With mitigation,
impacts to biological resources would be similar to those discussed in the FEIR and would
remain less than significant with the proposed Project modifications.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no changes with respect to circumstances under which the Project will be undertaken,
and there is no new information of substantial importance that has become available relative to
biological resources. The additional mitigation imposed by the California Coastal Commission and
the Regional Water Quality Control Board does not constitute a changed circumstance or new
information of substantial importance, as indicated in the First Addendum. The mitigation acreage
required by these two agencies was imposed pursuant to their respective responsibilities under
separate regulatory schemes, i.e., the Coastal Act and the California Water Code, both of which
employ different standards of review than CEQA’s “significant impact” threshold. Thus, the
additional mitigation acreage did not involve new significant environmental effects or a substantial
increase in the severity of previously identified significant effects.
Conclusion
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None of the proposed Project changes or additions regarding biological resources involve new
significant impacts or a substantial increase in previously identified impacts. Additionally, there
are no substantial changes to the circumstances under which the Project will be undertaken,
and no new information of substantial importance regarding biological resources which was not
known and could not have been known when the FEIR was certified has since been identified.
Therefore, the biological resources impacts and the proposed Project modifications do not meet
the standards for a subsequent or supplemental EIR as provided pursuant to CEQA Guidelines,
Section 15162.
Cultural Resources
Analysis of cultural impacts and EIR-identified mitigation measures of the approved Project are
contained in the FEIR, Section 4.4, pages 4.4-14 through 4.4-27. See also CEQA Findings,
pages 14 and 15.
The FEIR and First Addendum concluded that cultural resource impacts were less than
significant with mitigation implemented in previously undisturbed areas near known
archaeological and paleontological resources sites.
Analysis of the Revised Project
With the exception of the Macario Canyon Pumping Well, the proposed Project modifications
would occur entirely within existing pipeline ROWs or in areas that have been previously
disturbed. Therefore, no new impacts to cultural or paleontological resources would result
from the proposed Project modifications in the areas of existing infrastructure, and no cultural
resources mitigation beyond that identified in the FEIR would be required for these proposed
Project modifications. The Macario Canyon Pumping Well construction area was surveyed
and no cultural resources were identified. As a result, implementation of project work at this
location would not have an effect on cultural resources. Any work conducted at this site would
also be subject to the mitigation in Section 4.4.4 of the FEIR, as applicable. Implementation of
these mitigation measures would ensure that impacts remain less than significant. Therefore,
the proposed Project modifications would not result in new significant impacts or increase the
severity of impacts identified in the FEIR, and therefore would not change the FEIR
conclusion.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
The potential for significant impacts on cultural or paleontological resources within the area of
potential effect of the Project has not changed since the time of certification of the FEIR.
Therefore, no changes in circumstances and no new information of substantial importance
relative to cultural or paleontological resources have been identified.
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Conclusion
None of the proposed Project modifications involve new significant impacts or a substantial
increase in previously identified impacts regarding cultural/paleontological resources.
Additionally, there are no substantial changes to the circumstances under which the Project will
be undertaken, and no new information of substantial importance regarding
cultural/paleontological resources which was not known and could not have been known when
the FEIR was certified has since been identified. Therefore, the impacts to
cultural/paleontological resources as a result of the proposed Project modifications do not meet
the standards for a subsequent or supplemental EIR as provided pursuant to CEQA Guidelines,
Section 15162.
Geology and Soils
Analysis of geology/soils impacts and EIR-identified mitigation measures of the approved
Project are contained in the FEIR, Section 4.5, pages 4.5-10 through 4.5-17. See also CEQA
Findings, pages 15 and 16.
The FEIR and First Addendum found that long-term impacts due to unstable soil types and
seismic-related geologic hazards would be less than significant with mitigation measures
incorporated. The FEIR and First Addendum also found that during construction activities,
erosion could be accelerated, which could undermine slopes, cause siltation of surface waters,
and expose and damage underground facilities. This impact was found to be less than
significant with implementation of mitigation measures. Additionally, the FEIR and First
Addendum found that impacts to mineral resources would be less than significant.
Analysis of the Revised Project
Geologic impacts of the proposed Project modifications would be mitigated to a less-than-
significant level with the implementation of Mitigation Measure 4.5-2, which requires that a pre-
construction geotechnical investigation be prepared to address geotechnical considerations. All
recommendations of the geotechnical investigation will be implemented.
The erosion potential for the proposed Project modifications would be similar to the approved
Project. Impacts would remain less-than-significant with the implementation of Mitigation
Measures 4.7-1 and 4.7-2, which require that the Project prepare a SWPPP and a Stormwater
Management Plan, respectively.
The footprints for the proposed Project modifications are within developed areas, adjacent to a
biological preserve area, or within the existing TOVWTP. These areas are not suitable for
mineral extraction. Therefore, the proposed Project modifications would not result in impacts to
geology and soils beyond what was originally evaluated in the FEIR and the First Addendum.
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Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There is no potential for significant changes in geological, seismic, soils, or mineral resource
conditions within the area of potential effect of the Project since the time of certification of the
FEIR, because such resources are relatively static. Additionally, no new information regarding
unknown geologic hazards, conditions, or resources has become available. Therefore, no
changes in circumstances and no new information of substantial importance relative to geology
have been identified.
Conclusion
None of the changes or additions to the proposed Project modifications involve new significant
impacts or a substantial increase in previously identified impacts to geology, soils, or mineral
resources. In addition, there are no substantial changes to the circumstances under which the
Project will be undertaken and no new information regarding geological resources which was
not known and could not have been known when the FEIR was certified has since been
identified. Therefore, the geology/soils impacts and the proposed Project modifications do not
meet the standards for a subsequent or supplemental EIR pursuant to CEQA Guidelines,
Section 15162.
Hazards and Hazardous Materials
Analysis of hazards impacts and EIR-identified mitigation measures of the approved Project are
contained in the FEIR, Section 4.6, pages 4.6-9 through 4.6-17. See also CEQA Findings,
pages 16 and 17.
The FEIR determined that Project construction would require grading and trenching that could
potentially disturb and release hazardous materials into the environment from sites located in
proximity to the construction areas. Potential for release or exposure of existing subsurface
contamination could result during construction. The FEIR included measures to mitigate this
potential for exposure to existing contamination sites during construction. Specifically, FEIR
Mitigation Measure 4.6-1 would mitigate the potential for exposure of existing contamination by
requiring construction monitoring in areas identified as having potential risks, and appropriate
actions to be taken if contamination is encountered.
Analysis of the Revised Project
During construction, ground-disturbing activities such as grading or excavation associated with the
proposed Project modifications are not anticipated to encounter contaminated soils. The proposed
Project modifications would occur at an existing water treatment facility, along an existing water
distribution pipeline, or along a previously approved pipeline alignment adjacent to a biological
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preserve. However, to ensure that impacts would remain less than significant, the proposed Project
modifications would be subject to FEIR Mitigation Measure 4.6-1 mentioned above.
During construction, gasoline, diesel fuel, lubricating oil, grease, solvents, paint, and welding
gases would be used at all proposed Project locations. The Project would implement FEIR
Mitigation Measure 4.7-1, which requires that the Project prepare and implement an SWPPP that
will include both construction and post-construction pollution prevention and pollution control
measures. Additionally, as part of the Water Authority’s water treatment and distribution facilities,
the proposed facilities that would be owned and operated by the Water Authority would be subject
to the Water Authority’s Emergency Response Plan (ERP), which requires that the Water
Authority, in conjunction with the local fire department, take appropriate response actions in the
case of an accidental release of hazardous materials during transportation, use, or disposal of
hazardous materials (Water Authority 2003). With the implementation of the Water Authority’s
ERP and FEIR Mitigation Measure 4.7-1, potential impacts related to hazards and hazardous
materials during construction would be similar to the approved Project and would remain less than
significant with the proposed Project modifications.
Impacts related to hazards and hazardous materials for each Project modification are
discussed below.
TOVWTP Modifications
The FEIR and First Addendum concluded that with appropriate handling and mitigation for
chemicals proposed to be used for treating the product water, potential long-term impacts related to
a risk of exposure, including fire or hazardous vapor releases during operations, will be less than
significant. The proposed Project modifications at the TOVWTP include a chemical injection and
monitoring station, which would inject aqueous ammonia and sodium hypochlorite into the product
water to provide disinfection. These chemicals are currently stored and used on site. The proposed
additional chemical volumes would be subject to compliance with all applicable hazardous materials
storage and handling laws and regulations, and Fire Code requirements, which the current
treatment plant is subject to and in compliance with. With the proposed Project modifications, the
Water Authority will update all applicable documentation at the site, such as the treatment plant’s
Hazardous Materials Business Plan. The treatment facility with the proposed Project modifications
would also be subject to the Water Authority’s ERP, as discussed previously. With compliance with
all applicable laws and implementation of the Water Authority’s ERP, long-term impacts from
hazards and hazardous materials at the treatment plant site would remain less than significant.
Aqueduct Connection Point Modifications
As mentioned previously, in very rare circumstances, product water from the Carlsbad
Desalination Project may be directly delivered south in the Water Authority’s aqueduct. If
needed in certain instances a chemical injection facility will be installed to assure acceptable
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water quality at the San Marcos connection point to treat the product water prior to introduction
into the Water Authority’s aqueduct. These facilities would only be used when the water is
routed to the south rather than north to the TOVWTP. This is not a normal operation mode and
would only be required in rare circumstances where Pipeline 3 or Pipeline 4 are out of service
upstream of the desalination connection facilities. This chemical injection facility would consist
of two 5,000-gallon tanker trucks temporarily parked within secondary containment structures.
One truck would contain sodium hypochlorite (11%–14% solution) and one truck would contain
aqueous ammonia (17%–20% solution). The sodium hypochlorite would be injected into the
product water at a rate of 700 gal/day. The ammonia would be injected at a rate of 350 gal/day.
Approximately one sodium hypochlorite truck delivery a week and one aqueous ammonia truck
delivery every 2 weeks would be required during periods when chemical injection is in use.
As discussed in the FEIR, chlorine does not pose a public health hazard when stored in the form
of liquid bleach (sodium hypochlorite), and aqueous ammonia presents a significantly lower risk of
toxic plume release when stored in quantities below the Clean Air Regulations threshold of 20,000
gallons at concentrations above 20% (40 CFR 68, Section 130). The proposed additional
chemical volumes would be subject to compliance with all applicable hazardous materials storage
and handling laws and regulations, as well as Fire Code requirements, per Mitigation Measure
4.6-3 in the FEIR. The proposed Project modifications would not result in new impacts or
increased severity of impacts beyond those previously identified in the FEIR.
Pipeline 3 Relining, Pipeline 4 Vent Replacement and Pipeline Interconnect, and Macario
Canyon Pipeline Alignment Modification and Pumping Well
As concluded in the FEIR, the use of pipelines to distribute potable water would not pose a
hazardous risk to the public or the environment. Long-term hazardous risks associated with the
Pipeline 3 Relining, the Pipeline 4 Vent Replacement and Pipeline Interconnect, and the
Macario Canyon Pipeline Alignment Modification and Pumping Well would be similar to the
impacts associated with the off-site pipeline impacts under the approved Project and, therefore,
impacts would remain less than significant.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no substantial changes to the circumstances under which the Project will be
undertaken, and there is no new information of substantial importance relative to hazards or
hazardous materials that has become available since the certification of the FEIR.
Conclusion
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With consideration of the above discussion, the hazards and hazardous materials impacts and
the proposed Project modifications do not meet the standards for a subsequent or supplemental
EIR as provided pursuant to CEQA Guidelines, Section 15162.
Hydrology and Water Quality
Analysis of hydrology/water quality impacts and EIR-identified mitigation measures of the
approved Project are contained in the FEIR, Section 4.7, pages 4.7-10 through 4.7-25. See also
CEQA Findings, pages 17 through 20.
The FEIR and First Addendum concluded that construction of the approved Project could result
in significant short-term surface water quality impacts associated with exposed soils, fuels,
lubricants, and solid and liquid wastes that would be used and stored within active construction
areas. Mitigation Measures 4.7-1 and 4.7-2, which require that the Project prepare an SWPPP
and, if appropriate, a Stormwater Management Plan (if grading or building permits are
determined to be necessary) were found to reduce water quality impacts to less than significant.
Analysis of the Revised Project
TOVWTP Modifications
Regional groundwater within the area of the TOVWTP site occurs at depths of approximately 90
feet below the surface. Additionally, localized perched groundwater aquifers are considered
possible within the Project site and typically vary in volume and extent based on seasonal
precipitation and/or irrigation levels (Water Authority 2005). Groundwater is not anticipated to
occur at the relatively shallow depths of disturbance necessary for the proposed Project
modifications. As such, impacts to groundwater would be less than significant.
Pipeline 3 Relining, Aqueduct Connection Point Modifications, Pipeline 4 Vent Replacement and
Pipeline Interconnect, and Macario Canyon Pipeline Alignment Modification and Pumping Well
Both the FEIR and First Addendum concluded that impacts to hydrology and water quality due to
installation of the off-site pipelines and associated infrastructure would be less than significant. The
majority of the proposed Project modifications would be installed or repaired underground and,
therefore, similar to the approved Project, would not cause increases in impervious surfaces or
runoff. Long-term impacts to hydrology and water quality from the proposed Project modifications
would therefore also be less than significant.
Similar to the approved Project, the proposed changes could also result in short-term
construction-related surface water impacts that would be reduced to less-than-significant levels
with implementation of FEIR Mitigation Measures 4.7-1 and 4.7-2.
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The proposed Project modifications located within the City of San Marcos are not located in a
flood zone (FEMA 1997, 1999). Portions of the Macario Canyon pipeline modifications are
within the flood zone that is a tributary to Aqua Hedionda Creek (FEMA 2012). The FEIR
determined that impacts may occur along certain pipeline alignments that are located within a
100-year flood zone. In these areas, implementation of Mitigation Measure 4.7-3, which requires
that construction activities occur during the dry months between May 1 and September 30,
ensures that impacts would remain below a level of significance. Consistent with the FEIR, the
Project with the proposed modifications would also implement Mitigation Measure 4.7-3 and
would not result in impacts associated with flood zones.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no substantial changes to the circumstances under which the Project will be
undertaken, and there is no new information of substantial importance relative to hydrology or
water quality that has become available since the certification of the FEIR.
Conclusion
The proposed Project modifications would not result in any new significant hydrologic/water
quality impacts, and no substantial increase in previously identified hydrologic/water quality
impacts would occur with implementation of applicable laws, regulation, and mitigation as
discussed above. Therefore, the impacts from the proposed Project modifications regarding
hydrology and water quality do not meet the standards for a subsequent or supplemental EIR
pursuant to CEQA Guidelines, Section 15162.
Land Use/Planning
Analysis of land use impacts and EIR-identified mitigation measures of the approved Project are
contained in the FEIR, Section 4.8, pages 4.8-10 through 4.8-20. See also CEQA Findings,
page 20.
The FEIR and First Addendum concluded that land use impacts would be less than significant.
Analysis of the Revised Project
The evaluation and findings from the FEIR and First Addendum do not change with the proposed
Project modifications. Modifications at the existing TOVWTP site would involve a new connection
from Pipeline 3 to the treated water storage tanks, and would occur entirely within Water
Authority’s water treatment plant site or existing ROW. A portion of this new connection would
occur on the treatment plant site, while a 300-foot-long pipeline segment would be located within
an existing road (terminus of El Paso Alto Road). Relining Pipeline 3 and modifications at the
Pipeline 4 Vent Replacement and Pipeline Interconnect site would also occur within an existing
Water Authority ROW. Construction would result in short-term impacts to surrounding land uses.
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Short-term impacts would include traffic delays, noise, visual effects, and dust, all of which are
within the scope of the analysis contained in the FEIR, as noted in the appropriate sections of this
Addendum. Land use impacts associated with the proposed Project modifications would be
similar to the approved Project; these impacts were found to be less than significant.
It is important to note that zoning ordinances do not apply to the location or construction of
facilities used for the production, generation, storage, or transmission of water (California
Government Code Section 53091). The policies and goals in both the Land Use Element and the
Public Facility Element of the County’s General Plan promote the efforts of the Water Authority
and water districts to provide for storage, treatment, and transmission facilities to meet demand
(County of San Diego 2010). Lastly, construction within existing roadways would not preclude
future use of roads following construction, as all of these project components would be located
underground.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no substantial changes to the circumstances under which the Project will be
undertaken, because there are no new land uses or substantial changes in land use policies or
requirements that would affect the Project. No new information of substantial importance relative
to land use has become available since the certification of the FEIR.
Conclusion
Based on the above, no new significant land use impacts or a substantial increase in previously
identified land use impacts would occur as a result of the proposed Project modifications.
Therefore, the impacts to land use and the proposed Project modifications do not meet the
standards for a subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Noise and Vibration
An analysis of noise impacts and EIR-identified mitigation measures of the approved Project are
contained in the FEIR, Section 4.9, pages 4.9-5 through 4.9-14. See also CEQA Findings,
pages 20 and 21. The FEIR analysis indicated that all Project-related construction activities
would comply with the local jurisdictions’ noise ordinance for allowable construction hours. Due
to compliance with construction noise restrictions, it is not anticipated that excavation and
installation of the pipelines using open trench installation methods would result in a significant
noise impact based on the applicable significance criteria. It was estimated in the FEIR that
maximum noise levels would range up to approximately 85 decibels (dB), while the average
sound level for an 8-hour work day was expected to range up to approximately 75 dB.
Further, the FEIR indicates that trenchless methods would be used at several areas. Noise
impacts associated with trenchless operations are similar to open trench pipeline construction.
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However, rather than the construction noise progressing linearly, the noise would be confined to
the excavated pits. Thus, noise impacts could last for several weeks rather than a few days at the
areas adjacent to the pits. Trenchless equipment would most likely include a microtunneling
machine, auger/drill, a crane, front-end loader, ventilation fans, air compressor, pumps, and dump
trucks. Excavating the pits would generally be the most intense noise source. Thereafter, the
noise impact would be less intense but a persistent noise source. Noise would be generated
primarily during the excavation of the launch and receiving pits. The construction specifications will
require the contractor to comply with the applicable noise ordinance. Construction noise would
not exceed established standards. Therefore, the noise impact is not anticipated to be significant.
Analysis of the Revised Project
TOVWTP Modifications
Noise levels resulting from construction activities associated with the proposed modifications at
the TOVWTP would be similar to those addressed in the Carlsbad FEIR. The County of San
Diego noise ordinance prohibits construction noise that exceeds an average sound level of 75
decibels for an eight-hour period, between 7 a.m. and 7 p.m., when measured at the boundary
line of the property where the noise source is located or on any occupied property where the noise
is being received. The proposed plant modifications would not result in more severe noise impacts
than those previously analyzed in the Carlsbad FEIR. Consistent with the Water Authority’s typical
construction practices, temporary noise walls would be incorporated into the Project as project
design features to reduce construction noise levels at nearby residences. With incorporation of
this design feature, noise levels at sensitive receptors are not expected to exceed the 85 dB
disclosed in the FEIR, and average sound levels for an 8-hour workday would remain below 75
dB due to the intermittent nature of construction activities on a day-to-day basis.
Once construction activities are complete, the proposed modifications to the treatment plant would
include the expansion of the flow control facility, the noise from which would be attenuated with
expansion of the noise attenuation features of the existing flow-control facility. The proposed
modifications at the treatment plant (pipelines, chemical injection, monitoring station, and pump
well) would be subject to the existing TOVWTP operational noise standards that require all
facilities on the TOVWTP site to not exceed a 1-hour average noise level of 45 dB at or beyond
the property lines. Therefore, the proposed modifications at the TOVWTP would not result in more
severe operational noise impacts than those considered in the FEIR, and would not exceed
existing TOVWTP operational standards.
Pipeline 3 Relining and Pipeline 4 Vent Replacement and Pipeline Interconnect
As indicated previously, the FEIR determined that compliance with construction noise
restrictions would ensure that temporary noise impacts remain less than significant. Portions of
the Pipeline 3 relining would occur in developed areas near sensitive noise receptors, such as
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residences, in certain locations along the pipeline alignment. The Pipeline 3 portals located in
the County of San Diego would not be located in close proximity to existing noise-sensitive
receptors. However, the portals located in the City of San Marcos would be located immediately
adjacent to existing residences, specifically at portals 11, 12, and 13 (see Figure 8, Pipeline 3
Relining – Portals Adjacent to Single-Family Homes).
Construction noise in the City of San Marcos is governed by Noise Ordinance Section 10.24.020
(City of San Marcos 2004). As indicated in the Noise Ordinance, construction activity would be in
violation of the ordinance if it were to occur at any time other than on weekdays Monday through
Friday between the hours of 7:00 a.m. and 6:00 p.m. and on Saturday 8:00 a.m. to 5:00 p.m. The
City of San Marcos does not have a numeric threshold for construction-generated noise.
The closest residences would be located adjacent to portals 11, 12, and 13. All construction
activity will be limited to the City of San Marcos’ permitted hours of construction. Consistent with
the Water Authority’s typical construction practices for relining projects, temporary noise walls
would be incorporated into the Project as project design features to reduce construction noise
levels at nearby residences. With incorporation of this design feature, noise levels at sensitive
receptors are not expected to exceed the 85 dB disclosed in the FEIR, and average sound
levels for an 8-hour workday would remain below 75 dB due to the intermittent nature of
construction activities on a day-to-day basis. Lastly, it should be noted that with the forward
progression of construction activities, construction would only occur for a limited duration
(approximately 2 to 3 months) at any given portal. Therefore, the Pipeline 3 relining would not
result in new significant impacts or increase the severity of impacts identified in the FEIR, and
would not change the FEIR conclusion that no significant noise impacts would occur.
Ground-borne vibration is typically attenuated over short distances. The closest home to the
portal locations would be approximately 25 feet or more from the construction area. The heavier
pieces of construction equipment utilized at the portals would have peak particle velocities of
approximately 0.089 or less at a distance of 25 feet (FTA 2006). At these distances and with
the anticipated construction equipment, the peak particle velocity would be below 0.1
inches/second at the adjacent homes, which is the point at which continuous vibration begins to
annoy people (Caltrans 2004). In addition, it would be well below 0.2 inches/second, which is
the magnitude typically used for protection of “fragile buildings” (ASCE 1974). As such, even
older homes that may exist adjacent to the portal locations would not be impacted by
construction. Construction is not anticipated to result in continuous vibration, nor is it expected
to exceed the magnitudes listed above. As such, the vibration impact would be less than
significant.
Construction associated with the Pipeline 4 Vent Replacement and Pipeline Interconnect would
also be limited to the City of San Marcos’ permitted hours of construction. In addition, there are
no sensitive receptors in the immediate vicinity of the site. Therefore, the Pipeline 4 vent
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replacement and pipeline interconnect would not result in new significant impacts or increase
the severity of impacts identified in the FEIR, and would not change the FEIR conclusion.
Once construction is complete, no operational noise is anticipated along the pipeline route as a
result of the relining or the vent replacement.
Macario Canyon Pipeline Alignment Modification and Pumping Well
As discussed in the FEIR, trenchless construction activities generate maximum noise levels of 85
dBA at approximately 50 feet. The actual sound level for an eight-hour work day would be
substantially less due to the intermittent nature of construction work and would range up to
approximately 75 dB at 50 feet. The FEIR concluded that due to the intermittent nature of
construction noise and the requirement in the construction specification to comply with all applicable
local noise ordinances, impacts to sensitive receptors during construction of the pipelines using
trenchless construction methods would be less than significant. The nearest noise sensitive receptor
to the proposed Macario Canyon modifications consist of apartments located approximately 1,200
feet to the north, across from Faraday Avenue. At this distance construction noise impacts would be
substantially less than those previously analyzed in the FEIR. Therefore, the proposed
modifications along the pipeline route would not result in any new significant noise impacts or more
severe construction noise impacts than those originally considered in the FEIR.
Additionally, consistent with the FEIR, implementation of Mitigation Measures 4.3-3, 4.3-4,
and 4.3-5, would ensure that indirect noise impacts to sensitive habitats and species remain
below a level of significance. Therefore, the Macario Canyon pipeline alignment modification
and pumping well would not result in new significant indirect noise impacts or increase the
severity of impacts identified in the FEIR, and would not change the FEIR conclusion.
Once construction is complete the pumping well would only be used in infrequent
circumstances, for limited periods of time and would not generate a substantial amount of noise,
and impacts would not be beyond the scope of those addressed in the FEIR. Similar to the
approved Project, operational noise impacts of the proposed Project modifications would be less
than significant.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no substantial changes to the circumstances under which the proposed Project
modifications will be undertaken, because there are no new substantial changes in noise or
vibration policies or requirements that would affect the Project. No new substantial sources of
noise or vibration would be introduced within the area, and no new information of substantial
importance relative to noise and vibration has become available since the certification of the FEIR.
Conclusion
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Based on the above, no new significant noise or vibration impacts or a substantial increase in
previously identified noise impacts would occur as a result of the proposed Project modifications.
Therefore, noise and vibration impacts and the proposed Project modifications do not meet the
standards for a subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
FIGURE 4I
PORTAL 12
PORTAL 11
PORTAL 13
Portal Impact
Staging Area Impact
CWA Right-of-Way
Study Area
FIGURE 8
Pipeline 3 Relining - Portals Adjacent to Single Family Homes
Second Addendum to the Carlsbad Desalination Plant Project FEIR7250
AERIAL SOURCE: BING MAPPING SERVICE
0350175Feet
Z:\Projects\j725001\MAPDOC\MAPS\Cbad Desal Addendum 2 Figs\Figure8 Portals 11-12-13.mxd
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INTENTIONALLY LEFT BLANK
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Transportation and Traffic
Analysis of traffic impacts and EIR-identified mitigation measures of the approved Project are
contained in the FEIR, Section 4.10, pages 4.10-4 through 4.10-13. See also CEQA Findings,
pages 21 and 22.
The FEIR and First Addendum concluded that the approved Project would result in short-term
construction traffic impacts associated with the portions of the off-site pipeline that is to be located
within existing roadways. Temporary construction traffic trips include crew vehicles and deliveries
of pipeline and other materials. The FEIR and First Addendum included Mitigation Measures 4.10-
1 and 4.10-2 that require that construction will not result in unacceptable levels of service during
peak hour periods on any affected roadways, and that specific traffic control measures as set forth
within an approved traffic control plan are implemented. With implementation of these mitigation
measures, traffic impacts were considered less than significant.
The FEIR and First Addendum also concluded that long-term traffic impacts from inspection and
monitoring activities would be less than significant.
Analysis of the Revised Project
The proposed Project modifications would have similar short-term construction related impacts
as those disclosed in the FEIR and First Addendum. Since the proposed Project modifications
would add a connecting pipeline to an existing treatment plant, reline an existing pipeline,
replace an existing vent and add an interconnection pipeline, and add a pumping well to an
approved pipeline, trips associated with inspection of these facilities are considered previously
approved and are not considered new traffic trips. Following construction, the proposed Project
modifications at the TOVWTP would not result in an increase in staffing at the facility and no
additional trips would occur. As discussed above, during periods when the water is sent south
from the Aqueduct Connection Point, approximately one or two truck deliveries a week would be
required to supply the chemical injection tankers. The proposed Project modifications would not
result in a substantial increase in traffic on local roadways. Therefore, long-term impacts to
transportation and traffic would be similar to the approved Project and impacts would remain
less than significant.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no substantial changes under which the Project will be undertaken, because there are
no substantial changes in traffic characteristics or requirements from what was in place at the
time that the FEIR was certified. No new information of substantial importance relative to traffic
has become available since the certification of the FEIR.
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Conclusion
Based on the above, no new significant traffic impacts or a substantial increase in previously
identified traffic impacts would occur as a result of the proposed Project modifications.
Therefore, the traffic impacts and the proposed Project modifications do not meet the standards
for a subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Public Utilities and Service Systems
Analysis of public utilities and service impacts and EIR-identified mitigation measures of the
approved Project are contained in the FEIR, Section 4.11, pages 4.11-6 through 4.11-22. See
also CEQA Findings, pages 23 through 25.
The analysis of public services and utilities in the Carlsbad Desalination FEIR and First
Addendum concluded that the water treatment plant and associated infrastructure would not
result in significant impacts to fire protection services, schools, wastewater treatment facilities,
landfills, stormwater drainage facilities, or electric power services.
Analysis of the Revised Project
The proposed Project modifications would not result in residential, commercial, or industrial
growth, and therefore, similar to the approved Project, would not require additional services or
utilities. The revised Project would not result in an increase in the maximum energy use that
was contemplated in the FEIR. All energy use required to deliver product water to the
components of the proposed Project modifications would be incurred by pumps at the Carlsbad
Desalination Plant, and this energy use was previously analyzed in the FEIR.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no substantial changes under which the Project will be undertaken, because there are
no substantial changes in public utilities or services, or to the requirements of agencies that
provide such services, from what was in place at the time that the FEIR was certified. No new
information of substantial importance relative to public utilities or services has become available
since the certification of the FEIR.
Conclusion
Based on the above, no new significant public utilities and service system impacts or a
substantial increase in previously identified public utilities and service system impacts would
occur as a result of the proposed Project modifications. Therefore, the public utilities and service
system impacts and proposed Project modifications do not meet the standards for a subsequent
or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
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9.0 CUMULATIVE IMPACTS
Analysis of cumulative impacts and EIR-identified mitigation measures of the approved Project
are contained in the FEIR, Section 5.0, pages 5-1 through 5-13. See also CEQA Findings,
pages 25 through 27.
Analysis of the Revised Project
The type and extent of construction activities and the operational characteristics of the proposed
Project modifications would not be substantially different from what was evaluated in the FEIR
for the approved Project. Therefore, no changes relative to the analysis or conclusions regarding
cumulative impacts would occur with the proposed Project modifications, and the findings of the
FEIR and First Addendum remain the same for the revised Project.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
Since certification of the FEIR and adoption of the First Addendum, minor additional cumulative
development may have been proposed and/or constructed. However, the analysis contained in
the First Addendum occurred during a severe economic downturn, which has resulted in a
virtual curtailment of development activities within the Project area. The minor amount of land
development projects that have been proposed and/or developed in the intervening time since
the preparation of the First Addendum is not considered to be substantial. The following
provides a cumulative analysis of the proposed Project modifications.
Aesthetics
Because the proposed Project modifications are minor and they have been designed to have
minimal visual impacts, the incremental effect of the proposed Project modifications on any
potential significant cumulative impact would not be cumulatively considerable.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative aesthetic
impacts which was not known and could not have been known when the FEIR was certified and
First Addendum adopted that has since been identified. Therefore, the effects of additional
cumulative development regarding cumulative aesthetic impacts do not meet the standards for a
subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Air Quality
The Project’s contribution to temporary regional air quality impacts is not considered to be
significant. In addition, because Project construction occupies a relatively small area at any
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given time, it is not anticipated that any significant localized cumulative impacts will result. This
is primarily due to the short-term nature of cumulative effects within any given location along the
Project construction route. Any additional cumulative development would not change these
conclusions because the scope of the cumulative development is relatively small within the
context of the air basin, and because as noted in the FEIR, construction-related emissions
would be short-term in nature. There would be no new operational air pollutant emissions not
already considered in the FEIR or First Addendum.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative air quality
impacts which was not known and could not have been known when the FEIR was certified that
has since been identified. Therefore, the effects of additional cumulative development
regarding cumulative air quality impacts do not meet the standards for a subsequent or
supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Biological Resources
As noted in this Addendum, the proposed Project modifications do not involve new significant
impacts or a substantial increase in previously identified impacts. This conclusion would not be
changed with additional cumulative development due to the limited scope of cumulative
development.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative biological
impacts which was not known and could not have been known when the FEIR was certified that
has since been identified. Therefore, the effects of additional cumulative development
regarding cumulative biological impacts do not meet the standards for a subsequent or
supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Cultural Resources
The FEIR cumulative impacts analysis for cultural resources concluded that impacts on cultural
resources related to cumulative development could be significant if important cultural resources
are destroyed as a result of development. The mitigation measures required for the proposed
Project provides for avoidance, documentation, and/or recovery of important cultural resources,
and as a result, all impacts related to cultural resources are reduced to less-than-significant
levels. These same measures would apply to any additional cumulative development, and
therefore the level of cumulative impact and required mitigation measures would not change.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative cultural
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resource impacts which was not known and could not have been known when the FEIR was
certified that has since been identified. Therefore, the effects of additional cumulative
development regarding cumulative cultural resource impacts do not meet the standards for a
subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Geology and Soils
The FEIR concluded that the desalination plant site and off-site facilities will require relatively
minor site preparation and excavation of soils. Project mitigation to control and address erosion
and seismic and soils hazards, in conjunction with similar standard measures required of
cumulative development, would reduce cumulative impacts to less-than-significant levels. Any
additional cumulative development would have similar levels of impact on geology and soils and
would be subject to similar requirements and mitigation measures.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative
geology/soils impacts which were not known and could not have been known when the FEIR
was certified that has since been identified. Therefore, the effects of additional cumulative
development regarding cumulative geology/soils impacts do not meet the standards for a
subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Hazards and Hazardous Materials
The Project, as well as other cumulative development, would be subject to regulatory controls
that would result in minimization of hazards, and therefore the FEIR concluded that the Project
would not contribute to cumulative considerable increases in hazards or hazardous materials.
Any additional cumulative development would have similar regulatory controls.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative hazard
impacts which was not known and could not have been known when the FEIR was certified that
has since been identified. Therefore, the effects of additional cumulative development
regarding cumulative hazards impacts do not meet the standards for a subsequent or
supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Hydrology and Water Quality
The FEIR concluded that water quality and hydrology issues would be temporary (construction-
related) in nature and would not contribute to cumulatively significant impacts. Impacts of any
additional cumulative development would be similar, and in fact would be subject to newer more
stringent regulatory control measures.
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There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative
hydrology/water quality impacts which was not known and could not have been known when the
FEIR was certified that has since been identified. Therefore, the effects of additional cumulative
development regarding cumulative hydrology/water quality impacts do not meet the standards
for a subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Land Use and Planning
The FEIR concluded that the Project would not contribute to significant impacts resulting from
cumulative development that may have the effect of dividing an established community or
conflicting with land use or environmental policies. Therefore, the incremental effect of the
Project on any potential significant cumulative impact would not be cumulatively considerable.
This conclusion would also apply to any additional cumulative development.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative land use
impacts which was not known and could not have been known when the FEIR was certified that
has since been identified. Therefore, the effects of additional cumulative development
regarding cumulative land use impacts do not meet the standards for a subsequent or
supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Noise and Vibration
The FEIR identified cumulative noise and vibration impacts to be primarily related to construction
noise. However, within the time frame of Project construction, it is not anticipated that those
cumulative effects would reach a level of significance because of noise restrictions required for
construction projects, and because the time frame for construction of the proposed Project is
relatively short. Any additional cumulative development would not change these conclusions
because of the short duration for construction of the proposed Project modifications.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative noise and
vibration impacts which was not known and could not have been known when the FEIR was
certified that has since been identified. Therefore, the effects of additional cumulative
development regarding cumulative noise and vibration impacts do not meet the standards for a
subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
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Transportation and Traffic
The cumulative impacts analysis for transportation and traffic considered the intersections and
road segments to which the desalination plant and off-site facilities could contribute to a
cumulative impact. Similar to noise impacts, Project traffic impacts are primarily associated with
construction. Since the time frame for construction is relatively short and traffic control plans to
minimize traffic impacts are required, it is not anticipated that a substantial increase in current
traffic levels resulting from cumulative development will occur prior to completion of Project
construction. Therefore, temporary traffic impacts associated with the Project will cease prior to
any substantial cumulative traffic impacts being realized on local roadways. Any additional
cumulative development would not change these conclusions because the construction travel
routes for the additional projects are not anticipated to substantially conflict with cumulative
construction traffic of the proposed Project.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative traffic
impacts which was not known and could not have been known when the FEIR was certified that
has since been identified. Therefore, the effects of additional cumulative development
regarding cumulative traffic impacts do not meet the standards for a subsequent or
supplemental EIR pursuant to CEQA Guidelines, Section 15162.
Public Utilities and Service Systems
The cumulative impacts analysis for energy and wastewater were considered to be less than
significant, primarily based on capacity and reliability features built into existing systems. The
additional cumulative development would not change the analysis or conclusions of the FEIR
because they would not result in substantial additional demand on such systems.
There are no substantial changes to the circumstances under which the Project will be
undertaken and no new information of substantial importance relative to cumulative
utilities/services impacts which were not known and could not have been known when the FEIR
was certified that has since been identified. Therefore, the effects of additional cumulative
development regarding cumulative utilities/services impacts do not meet the standards for a
subsequent or supplemental EIR pursuant to CEQA Guidelines, Section 15162.
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10.0 GROWTH-INDUCING IMPACTS
Analysis of growth-inducing impacts of the approved Project are contained in the FEIR, Section
9.0, pages 9-1 through 9-7. See also CEQA Findings, pages 54 and 55.
Analysis of the Revised Project
The proposed Project changes consist of minor modifications to the distribution system of the
Project, and necessary modifications to existing Water Authority facilities in order to accept, store
and distribute the Project water. The operation of the facility and its potable water-producing
capacity will not change from what was evaluated in the FEIR for the approved Project. Therefore,
no changes relative to the analysis or conclusions related to growth inducement would occur with
the proposed Project revisions.
Substantial Changes With Respect to the Circumstances Under Which the Project is
Undertaken/New Information of Substantial Importance
There are no substantial changes under which the Project will be undertaken, because there are
no substantial changes in growth potential or growth planning that would affect the analysis
contained in the FEIR. No new information of substantial importance relative to growth
inducement has become available since the certification of the FEIR.
11.0 CONCLUSION
Impacts associated with the proposed Project modifications would not result in a new significant
impact or substantial increase in the severity of previously identified impacts per the Carlsbad
Desalination Plant 2006 FEIR or the First Addendum. Additionally, where applicable (as
indicated in this Addendum), the proposed Project modifications would also not result in an
increase in the severity of previously identified impacts per the NCCP/HCP EIR/EIS. There are
no substantial changes to the circumstances under which the Project will be undertaken, and no
new information of substantial importance which was not known and could not have been
known when the FEIR was certified and the First Addendum was approved, and that have since
been identified. Therefore, the proposed Project modifications do not meet the standards for a
subsequent or supplemental EIR as provided pursuant to CEQA Guidelines, Section 15162. As
such, this Second Addendum to the FEIR satisfies CEQA requirements for the proposed Project
modifications.
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12.0 REFERENCES
ASCE (American Society of Civil Engineers). 1974. Journal of Construction Division, Vibrations
During Construction Operations, 100 No. CO3, pp. 239–246, September 1974.
Caltrans (California Department of Transportation). 2004. Transportation Related Earthborne
Vibrations. January 23, 2004.
City of Carlsbad. 2006. Carlsbad Precise Development Plan and Desalination Plant Final
Environmental Impact Report. Certified June 13, 2006.
City of Carlsbad. 2008. Preserve Management Plan, September. Accessed on March 5, 2012
at: http://www.carlsbadca.gov/services/environmental/hmp/docs/Documents/preserves-
mgmt-plans/city-preserves-pmp-2008.pdf.
City of Carlsbad. 2009. CEQA Addendum for the Precise Development Plan and Desalination
Plant Project Final EIR. August 2009.
City of San Marcos. 2004. City of San Marcos Municipal Code, Chapter 10.24, Noise.
November 4, 2004.
County of San Diego. 2010. General Plan, as amended. Accessed March 31, 2010.
http://www.sdcounty.ca.gov/dplu/docs/existgp/landuse.pdf.
Dudek. 2012. Biological Resources Technical Report for the Pipeline 3 Relining and Associated
Improvements Project. November 2012.
FEMA (Federal Emergency Management Agency). 1997. Flood Insurance Rate Map, San Diego
County, California and Incorporated Areas, Panel 783 of 2375. Map Number
06073C0783 F. Map Revised June 19, 1997.
FEMA. 1999. Flood Insurance Rate Map, San Diego County, California and Incorporated Areas,
Panel 789 of 2375. Map Number 06073C0789 G. Map Revised June 16, 1999.
FEMA. 2012. Flood Insurance Rate Map, San Diego County, California and Incorporated Areas,
Panel 768 of 2375. Map Number 06073C0768G. Map Revised May 16, 2012.
FTA (Federal Transit Administration). 2006. Transit Noise and Vibration Impact Assessment.
SDCRWQCB (San Diego County Regional Water Quality Control Board. 2012. San Diego
Region (9) Hydrologic Basin Planning Area. Revised April 1995. Accessed on February
1, 2012 at http://www.swrcb.ca.gov/sandiego/water_issues/programs/basin_plan/.
Precise Development Plan and Desalination Plant Project November 2012
Second CEQA Addendum 66
Water Authority (San Diego County Water Authority). 2003. Regional Water Facilities Master Plan,
Final Program Environmental Impact Report. November 2003.
Water Authority. 2005. Twin Oaks Valley Water Treatment Plant Final EIR, Volumes I-III.
September 2005.
Water Authority. 2010a. Final Environmental Impact Report/Environmental Impact Statement
(EIR/EIS) for the San Diego County Water Authority Subregional Natural Community
Conservation Plan/Habitat Conservation Plan. State Clearinghouse No. 2003121012.
October 2010.
Water Authority. 2010b. Natural Community Conservation Plan/Habitat Conservation Plan.
October 2010.
Water Authority, U.S. Fish and Wildlife Service, and California Department of Fish and Game.
2010. Implementing Agreement for the San Diego County Water Authority Natural
Community Conservation Plan/Habitat Conservation Plan. October 18, 2010.