Anaheim Bay Bridge Rock Slope Protection Mitigation
and Restoration Plan
State Route 1 (Pacific Coast Highway)
Kilo post 51.1/51.1
Post Mile 31.7/32.2
EA 078004
Prepared for:
California Coastal Commission
California Department of Fish and Game
Prepared by:
Karen Drewe
Associate District Biologist
California Department of Transportation
Environmental Planning, District 12
3337 Michelson Drive, Suite 380
Irvine, California 92612
May 2007
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I.
INTRODUCTION
The California Department of Transportation (Caltrans) and Federal Highway Administration
(FHWA) propose to repair the rock slope protection at Anaheim Bay Bridge on State Route
1, also known as Pacific Coast Highway, in Orange County at Post Miles 31.7 to 32.2. The
proposed project is located in the City of Seal Beach, and at the Seal Beach Naval Weapon
Station. The current condition of the bridge includes rock slope protection that was placed
under the bridge, and along the abutments and sides of the bridge during the construction of
the bridge in 1968. The rocks have moved from the top of the bridge to the toe of the slope
and beyond. The current locations of rocks do not protect the bridge structure. Therefore, the
project will replace the rock slope protection to protect the bridge. The design of the rock
slope replacement will include all current design standards. North of the bridge, the current
conditions include four inlets on Route 1, and seven outlets that drain near the toe of the
roadway embankment on the north end of the project. The inlets, pipes, and outlets will be
repaired, and energy dissipaters will be installed at the outlet of the pipes. Four of the outlet
areas that will be impacted are within State and Federal wetlands.
The project is within the jurisdiction of the United State Army Corps of Engineers (USACE),
the California Department of Fish and Game (CDFG), the California Regional Water Quality
Control Board (CRWQCB), and the California Coastal Commission (CCC). Caltrans
received a letter from the USACE of denial without prejudice for our application for
Nationwide Permits Numbers 3, 13, and 33 pending the 401 Certification and CCC permit.
Caltrans has obtained the Section 401 Certification from the CRWQCB. Caltrans has
obtained the CDFG Streambed Alteration Agreement. And, Caltrans is in the process
meeting the requirements of the CCC permit (such as completing this Mitigation and
Restoration Plan). Caltrans, after coordination with several agencies and working with the
Engineers for construction constraints, anticipates that there will be no effects to State or
Federally protected species for the proposed project. Caltrans has been in contact with
United States Fish and Wildlife Service because of the proximity to the Seal Beach National
Wildlife Refuge. Furthermore, because of the presence of eelgrass beds near the proposed
project site, Caltrans has been in contact with the National Marine Fisheries Service (NMFS).
This Mitigation and Restoration Plan has been prepared and will be submitted to the
California Coastal Commission (CCC), and the California Department of Fish and Game
(CDFG) per the requirements of the CCC permit and the CDFG Streambed Alteration
Agreement. Although this Restoration and Mitigation Plan is not required by the United
State Army Corps of Engineers (USACE), this plan will be submitted to the USACE. This
Mitigation and Restoration Plan has been prepared following U.S. Army Corps of Engineers,
Los Angeles District, Habitat Mitigation and Monitoring Proposal Guidelines, September
2002.
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II.
PROJECT DESCRIPTION
1. Project Location
The proposed project is located at the Anaheim Bay Bridge on Route 1 (Pacific Coast
Highway) in the City of Seal Beach, Orange County (Appendix A). The bridge crosses over
the inlet connecting outer and inner Anaheim Bay and Sunset Bays surrounded by the Seal
Beach Naval Weapons Station and the Seal Beach National Wildlife Refuge. The proposed
work requires an encroachment permit from the Naval Weapon Station to allow access to the
area under the bridge. Activities include work to be conducted under the bridge along all four
abutments, and on the north (bay side) areas along the roadway slope. Furthermore, the work
includes seven drainages located on the north-east quadrant, and a maintenance pullout
station on the north-west quadrant.
Anaheim Bay and the Seal Beach National Wildlife Refuge lie immediately north (bayside
area) of the proposed project area. The Seal Beach Naval Weapon station includes the area
south of the proposed project, and therefore, a temporary construction easement is required to
complete the construction phase of the propose project. The proposed project site is found on
the USGS 7.5 minute topographic map for Seal Beach, Township 5, Range S, and Section 12.
The Latitude is N 33044’ and Longitude of West 118 04’.
2. Project Summary
The proposed project will protect Anaheim Bay Bridge by reconstructing the current
abutments and roadway embankments to a 1:1.5 slope, placing rock slope protection over the
slope to join the existing eroded rocks up to an elevation of four meters, and installing erosion
control blanket from elevation of four meters up to the top of the slope; replacing two metal
beam guard rail ends; installing chain link fence; constructing a maintenance vehicle pullout;
lining existing drainage pipes, constructing four new inlets and reconstructing seven existing
outlets. The proposed project includes landscaping and restoration work. It includes grading
of the north-east existing roadway embankment, adjacent to the rock slope protection, to a
1:1.5 slope and using native species of plants for the re-vegetation. The re-vegetation will
include planting pickleweed and other wetland species at the toe of the slope and coastal sage
scrub species on the top of the slope (Appendix B).
3. Responsible Parties
The Project Manager is Nooshin Yoosefi. She may be reached at 949-724-2131, or
Nooshin_Yoosefi@dot.ca.gov.
The Project Design Engineer is Andrew Oshrin. He may be reached at 949-724-2128, or
Andrew_Oshrin@dot.ca.gov.
The Project Biologist is Karen Drewe. She may be reached at 949-724-2850, or
Karen_Drewe@dot.ca.gov.
The Project Landscape Architect is Ronald Wong. He may be reached at 949-724-2865, or
Ronald_Wong@dot.ca.gov.
4. Jurisdictional Areas to be Effected by Habitat Type
The jurisdictional areas that will be affected by the proposed project include areas below the
Mean High Water (MHW) that are non-federal wetlands, federal wetlands, and areas above
the MHW that are outside the USACE but are located within the CCC jurisdiction. Appendix
C includes an aerial photograph with the habitat types overlaid. The habitat type at the
bridge, and within the project limits, are open water, and non-wetlands per federal standards.
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At the toe of the slope, and outside the project limits, some rocky intertidal species are found.
Also, outside the project limits, eelgrass was found on the north-east quadrant. The habitat at
the top of the slope near the bridge is ruderal coastal sage (mostly goldenbush). The habitat
on the northern portion of the project includes areas of pickleweed at the project limits, and
outside the project. The slope area includes patches of ruderal coastal sage scrub, and areas
dominated by non-native and ornamental plants. Appendix D includes a chart showing the
areas affected by jurisdiction, and classified as temporary or permanent impacts.
The area that is below the MHW that is non-federal wetland will be temporarily and
permanently affected by the proposed project. Temporary effects include areas where the
rock slope protection is a replacement in-kind, the access routes, and grading areas. The area
where the rock slope protection is “new” to meet the requirement to protect the bridge and
roadway structure is a permanent impact. The grading areas on the north-east quadrant are
temporary effects to create lower elevations that will allow for the planting of pickleweed.
The four of the outlets are within the federal wetlands based on the three criteria of federal
wetlands (see Wetland Delineation January 2006).
5. Types, Functions and Values of the Jurisdictional Areas to be Directly or Indirectly
Impacted
The wetland areas to be affected by this proposed project are dominated by pickleweed
(Salicornia virginica) vegetation that is adjacent to iceplant (Carpobrotus edulis). One
purpose of grading the area on the north-east quadrant is to grade the slope at 1:1.5 so that
additional areas of wetland will be created by the proposed project. The area near the bridge
on the north-east quadrant, immediately adjacent to the project limits includes recently
discovered eelgrass beds (see Eelgrass report). Because the eelgrass area is not within the
proposed project limits, it is not anticipated to be impacted by the proposed project.
Furthermore, Best Management Practices will be implemented during construction to avoid
indirect effects to the eelgrass habitat. Directly under the bridge on both the north and south
location, the areas where the former rock slope protection moved down the slope to the
waters edge has become similar to other areas of rocky intertidal habitat. The rocky habitat
area will not be directly affected by the proposed project, and Best Management Practices
will prevent indirect effects to the rocky areas.
Although Anaheim Bay provides high function and values including water quality, habitat,
and public use, the areas within the project limits are likely to be considered moderate to low
because the area is on the edge of the habitat with Pacific Coast Highway bisecting the bay at
the bridge. This area consists of ruderal vegetation. The north-east quadrant has scattered
areas of ruderal coastal sage scrub habitat, some pickelweed, and areas of invasive species
(such as iceplant).
III.
MITIGATION GOALS
1. Habitat to be Created
The purpose of grading the slope to 1:1.5 is that it will lower the elevation allowing the area
to become dominated by wetland plant species at the toe of the slope, and with time, the area
should meet the three criteria of federal wetlands. The slope area above the Mean High
Water (MHW) will be vegetated with coastal sage scrub species. The restoration plan
includes an increase in plant diversity than the current types of plants found on-site. In
addition, there will be a weeding plan so that there will be no invasive plant species found in
the area after five years. The areas (including habitat) that will be impacted, and areas of
wetlands to be created are detailed in the Environmental Impact Areas chart (Appendix C),
and layout sheets plans (Appendix B). Temporary impacts to wetland areas will be restored
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on-site at a 1:1 ratio. The project will permanently impact 0.003 acres of federal wetlands,
and create 0.08 acres of wetlands. The project will permanently impact 0.02 acres of waters
of the U.S. (non-wetlands). The total permanent impacts to wetlands and non-wetlands
waters of the U.S are 0.023 acres. Therefore, the CCC requirement of 3:1 restoration for
permanent impacts will be met. Areas above the Mean High Tide Mark are within the CCC
jurisdiction. The areas of permanent impact due to the addition of rock slope protection (at
both the bridge and the drainage outlets) are 0.194 acres. The area to be graded and
revegetated with native plants is 1.90 acres. Within the 1.90 acres, there are currently some
native plants that will be destroyed during the grading. However, the replacement ratio
exceeds the 3:1 restoration to impact requirement of the CCC.
2. Function and Values of Habitat to be Created
The function and values of this area for habitat should be greater than prior to the
commencement of the proposed project because of the proposed grading, replanting using
only native plants, and weeding. The removal of invasive species such as iceplant will assist
in the prevention of the non-native plants from encroaching onto the USFWS Wildlife
Refuge. The installation of the rock slope protection at the drainage outlets provides velocity
dissipation of concentrated flows of storm water and prevents erosion of the slopes and
discharge of sediment from these concentrated flows from entering into the Seal Beach
National Wildlife Refuge.
3. Estimated Cost
The total cost estimate for the restoration plan is $712,000. The cost estimate for the planting
of the containers, seeding, and two years of weeding is $132,000. The grading of the slopes
to lower the elevation to create wetlands is $580,000.
4. Special Aquatic Habitats
Surveys for eelgrass (Zostera marina) were conducted because eelgrass beds were known to
be present on the south side of the bridge (Caltrans 2006). The surveys found that eelgrass
beds are present in the proximity of the project; however, the eelgrass is outside the project
limits. Surveys followed the Southern California Eelgrass Mitigation Policy (1991, as
amended, Revision 11). The surveys results for eelgrass and Caulerpa were submitted to
NMFS and CDFG in May 2006.
Pre-construction surveys will include eelgrass surveys prior to the commencement of
construction. Eelgrass beds can be negativity effected by siltation. Best Management
Practices will be implemented to minimize the siltation outside the proposed project limits.
At the completion of the proposed project, additional surveys will be conducted to determine
if the eelgrass areas were negatively affected by the project.
IV.
FINAL SUCCESS CRITERIA
Caltrans proposes the success criteria for area below the MHW near the toe of the slope to be
dominated by pickleweed. The area shall include 70 percent cover of native vegetation after
three years, and 80 percent cover at five years. The area will not include any invasive plant
species. In regards to the slope area, Caltrans has proposed several species of coastal sage
scrub that are not currently found on-site. Therefore, we anticipate greater native plant
diversity on the slopes compared to the current conditions. The proposed plant list is based
on a review and comments of a plant list submitted to the California Coastal Commission
(CCC). Caltrans proposes that the total native cover success be 70 percent at three years, and
75-80 percent cover at five years. Caltrans is not aware of an appropriate reference site to
compare the coastal sage scrub. A thorough literature review suggests that coastal sage scrub
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habitat is variable depending on several factors including location (such as proximity to the
coast) (e.g. Weaver 1998, Read 1994). Weaver (1998) found the composition and structure
of coastal sage scrub within San Diego to be variable, which was consistent with the work of
other scientists. An example of a resource agency requirement for coastal sage scrub
restoration and mitigation is the Biological Opinion (BO) on the Effects of the San Joaquin
Hills Transportation Corridor (SJHTC) on the Coastal California Gnatcatcher and Coastal
Cactus Wren; Orange County, California (1-6-93-F-98R). This BO indicated that the
revegetation would be considered acceptable coastal sage scrub habitat if the habitat was
occupied by breeding gnatcatchers, or if the habitat was insignificantly different (statistically)
from naturally-occurring gnatcatcher habitats, or fully functional coastal sage scrub in the San
Joaquin Hill, or if the total cover by native coastal sage scrub species in the restored sites was
at least 70 percent. Therefore, Caltrans is recommending that the success criteria be based on
the percent cover proposed in this Restoration and Mitigation Plan.
V.
PROPOSED MITIGATION SITE
The restoration site is a portion of the project site. The current plant list of container plants
has been reviewed, and has been updated per the comments from the CCC (see Appendix B).
Some of the current vegetation will be protected in place per the California Coastal
Commission request. Caltrans has surveyed the area of native vegetation, which consists of
species such as picklweed at the toe of the slope, and buckwheat, California sage brush,
coastal goldenbush near the top of the slope. The survey information was overlaid with
grading plans. Based on the information, the Engineers believe that some of these plants can
be left in place. The areas of plants to remain in place will be fenced with Environmental
Sensitive Areas fence, which is usually bright orange. The areas of plants to remain in place
are shown on plans in Appendix B.
VI.
IMPLEMENTATION PLAN
The success criteria are based on previous success criteria and information from CDFG and
USFWS. The restoration plan will be implemented as part of the construction contract. The
construction timing has restrictions due to bird nesting season (September to February), and
the tidal influence (work is only allowed in low tide). Therefore, the planting is anticipated to
be in the late winter of 2007. Although the construction work will be conducted from
September to 15 February, the work associated with the weeding and maintenance of the
plants as part of the construction project will be conducted during the bird nesting season.
1. Planting Plan
After the slope areas are graded, erosion control blankets will be installed, along with seeding
and the planting of container plants. The Grading Plans and planting plans, including the
seed list, are located in Appendix B. After the slope areas are graded, the erosion control
blankets will not use plastic netting. The project plans allow coconut fiber netting. Native
seeds will be used with the erosion control blanket. The container plants and the location of
these plantings are found in the Planting Plans.
2. Use of Native Plants
The Special Specifications of the Contract indicate the contractor shall use seed and container
plants from a genetic source within five miles of the coast within Orange or Los Angeles
County. However, if this requirement cannot be met, the genetic source of plants may be
outside of these limits.
The Caltrans Biologist has coordinated with the Survey crew to map the locations of native
plants within the proposed project limits. Because some of the native plants will remain in
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place (Appendix E), there should be some recruitment of native coastal sage scrub and salt
marsh plant species. We anticipate that because of the pickleweed growing adjacent to the
project limits, there should be natural recruitment of the plants within the restoration area.
3. Plant Establishment
The plant establishment will be for two years. The plant establishment will include weeding
of non-native and invasive species, irrigation as needed, and replacement of container plants
as needed. For additional information, please refer to the section below “Maintenance during
Monitoring Period”.
4. Irrigation Plan
The contractor will be required to provide temporary irrigation for the first two years of plant
establishment. The contractor may choose to use a truck to hand water the plants, or may
choose to install a temporary irrigation system. The contractor is responsible to remove any
temporary irrigation system that is installed at the site. Caltrans Standard Specification 204.06 Watering, states “Water shall be applied to plants as often and in sufficient amount as
conditions may require to keep the plants in healthy, growing condition during the life of the
contract.” There is not a set schedule of how often the plants will be watered.
VII.
MAINTENANCE DURING MONITORING PERIOD
The schedule of weeding and replacement of container plants is not based on working days,
rather it is base on the growth of weeds and the container plants. Weeds will be pulled before
the weed exceeds four inches in length (Caltrans Standard Specification Section 20-4.08).
Caltrans Standard Specification 20-4.07 states that “the Contractor shall complete
replacement of unsuitable plants within two weeks after the Engineer marks or otherwise
indicates that the plants shall be replaced. Per Caltrans Special Specifications after 6 months,
the replacement of any plants that die is based on the following: seedlings and liner size
plants will be replaced with one gallon containers, one gallon containers will be replaced with
five gallon containers, and five gallon containers will be replaced with 15 gallon containers.
The ground cover replacement is based on the spacing of the plants as described in the
following table:
ORIGINAL
SPACING
(Millimeters)
230
300
460
600
910
SPACING OF REPLACEMENT GROUND COVER PLANTS
(Millimeters)
Number of Completed Plant Establishment Working Days
1-180
181-275
276-End of Plant
Establishment
230
150
150
300
230
150
460
300
230
600
460
300
910
600
460
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VIII.
MONITORING PLAN
Yearly reports will be submitted to the appropriate resource agencies, and a final report will
be submitted at five years. The reports will include line-transects to show the percent total
cover of native plants, percentage of non-native plant species, and photographs of the site. A
Wetlands Delineation will be performed in the appropriate locations yearly. The Wetland
Delineation will be conducted as defined by the 1987 U.S. Army Corps of Engineers Manual.
In addition, any animals species observed within the area will be documented.
IX.
COMPLETION OF PLAN
Caltrans will submit a letter to the California Coastal Commission and the California
Department of Fish and Game when we believe the success criteria has been met requesting
concurrence from the resource agencies. If requested by the resource agencies, Caltrans will
meet with the resource agencies at the project site.
X.
REFERENCES
California Department of Transportation, District 12. January 2006. Wetlands Delineation
Report, Anaheim Bay Bridge Rock Slope Protection Project, Pacific Coast Highway, EA
078001.
California Department of Transportation, District 12. April 2006. Caulerpa taxifolia Survey
Reporting Form, Anaheim Bay Bridge Project.
California Department of Transportation, District 12. May 2006. Pre-construction eelgrass
(Zostera marina) Survey Report, Impact Analysis, and eelgrass protection plan. Anaheim
Bay Bridge Re-construction and Rock Slope Protection Project.
Read, Edith. 1994. The Importance of Community Classification to Mitigation and
Restoration of Coastal Sage Scrub. Restoration Ecology 2: 80-86.
United States Fish and Wildlife Service. 1994. Biological Opinion (BO) on the Effects of the
San Joaquin Hills Transportation Corridor (SJHTC) on the Coastal California Gnatcatcher
and Coastal Cactus Wren; Orange County, California (1-6-93-F-98R).
Weaver, Kenneth L. 1998. Coastal Sage Scrub Variations of San Diego County and Their
Influence o the Distribution of the California Gnatcatcher. Western Birds 29:392-405.
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E