HomeMy WebLinkAboutEIR 93-02; Green Valley; Environmental Impact Report (EIR) (46)September 27, 1993
Mr. John Gill, Chief Regulatory Branch DEPARTMENT OF THE ARMY
P. 0. Box 271 1 Los Angeles, CA 90053-2325
LA COSTA AVENUE PHASE II WIDENING
U.S. ARMY CORPS OF ENGINEERS NOTICE NO.. 93-868-EW
Dear Mr. Gill:
Thank you for your letter of August 16, 1993 informing us of the public and private responses
regarding Public Notice 93-868-EW.
- We have assembled all the necessary responses to these comments and concerns as follows:
1. California Coastal Commission Jurisdiction Letter, indicating that the project
requires the following:
A. Coastal Development Permit:
1 The City of Carlsbad applied and received a Coastal Development Permit for this project on August 12, 1993.
B. Consistency Determination:
This requirement is fulfilled by the issuance of a Coastal Development Permit by
the Coastal Commission. Please see the Coastal Commission’s letter, First Paragraph, Line 11.
2. San Diego Museum of Man Letter:
The cultural sites have been identified in the original Environmental Report issued in April 1986. These sites are all outside of the proposed alignment and did not require mitigation. However, it has been recommended that a paleontologist be present on the site during the grading operation.
California Reglonai Water Quality Control Board Letter Requesting that the City
Apply for Water Quality Certification:
3.
The City of Carlsbad will apply and secure a Water Quality Control Permit prior to the construction.
2075 Las Palmas Dr. . Carlsbad, CA 92009-1576 0 (619) 438-1161 FAX (61 9) 438-0894 @
September 27, 1993 LA COSTA AVENUE PHASE II WIDENING
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U.S. ARMY CORPS OF ENGINEERS NOTICE NO. 93-868-EW
4. State Lands Commissions' Letter, Requesting that the City Secure a Permit for
Constructing the Project on State Lands:
The City of Carlsbad has reviewed the project plans and has concluded that no State
Lands easement is involved or required for this project. The State Lands has been notified of the City's findings by a letter dated September 9, 1993, a copy of which is
attached.
5. U.S. Fish & Wildlife Service Letter Concerning the Status of Mitigation Areas:
The City of Carlsbad has prepared and submitted annual monitoring reports to the
permitting agencies since the completion of the Phase I and mitigation installation in
1987. The City's latest biological monitoring report, prepared in March of 1993, indicated
that out of six (6) mitigation areas, four (4) areas: 1 , 4, 5 and 6, encompassing 5.2 acres, have over 90% native species coverage. Only two (2) areas: 2 and 3 (2.2 acres), had less than acceptable growth. To bring these two areas to an acceptable level, and per
recommendation of the environmental consultant, OGDEN Environmental Group, the City
of Carlsbad prepared plans and specifications for remedial mitigation which required the use of plant species found to be most successful in the area. The remedial mitigation plans were mailed to permitting agencies, including Army Corps of Engineers and US. Fish and Wildlife, informing them of the City's implementation plans. The City received no response from the agencies. Subsequently, the City employed a contractor to install remedial mitigation, remove non-native species, replant and hydroseed areas 2 and 3,
and augment the successful areas by supplemental planting. The City's contractor is
required to maintain all six areas for a twelve (12) month period after the completion of
remedial planting and weeding. The contractor has been on th@ site since the beginning of August and has completed weed removal and has installed all the specified native container plants. The hydroseeding of native species will be accomplished within the next two weeks which will complete the remedial work and start the maintenance period.
The U.S. Fish and Wildlife's concern about the loss of satt marsh has been addressed in the OGDEN Environmental's Annual Report which indicated that the salt marsh mitigation was one of the most successful of the mitigated species, with over 90% success rate on
hydroseed and 80% success rate on container plant species.
The US. Fish and Wildlife recommendation to eliminate or minimize median width was addressed in the 1986 Environmental Report. Per recommendation of the U.S. Fish and
Wildlife, in 1986 the City reduced the median width from 18 to 8 feet. Based on various studies of medians, we believe that the elimination or any further reduction of the median width on La Costa Avenue would adversely affect the safety of the motorists and would increase the chances for head-on collisions. The American Association Of State Highway
and Transportation Officials (AASHTO) 1984 Edition, Page 403, under median width
discussion states that, The principal functions of medians are to provide the desired
freedom from the interference of opposing traffic, to provide a recovery area for out-of-control vehicles," AASHTO also indicates that medians should be as wide as
feasible.
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U.S. ARMY CORPS OF ENGINEERS NOTICE NO. 93-868-EW
The US. Fish and Wildlife's recommendation of abandonment of the existing mitigation
sites and acquisition of alternate sites is at best puzzling to us, since these sites and
specified native plant species were identified as the most suitable for mitigation by the
U.S. Fish & Wildlife in 1986. Based on F&W requirement, the City with great difficulty and
through condemnation procedures, purchased the mitigation areas at significant costs.
The total costs of the mitigation to date is well over $1 ,OOO,OOO. Please also note that the
existing mitigation areas with 90% success rate are installed at the rate of 3.3 to 1 ratio. This higher replacement ratio guaranteed the success and replenishment of native material.
Lost acreage: Mitigated acreage:
Salt marsh 1.5 acres riparian woodland 0.9 acres 3.3 acres x 35% success rate = 1'16 acres
4.95 acres x 90% success rate = 4.46 acres
Total acreage lost: 2.4 acres Total acreage successful: 5.62
The area of successful mitigation is 2.34 times the disturbed area.
rc Since the specified species and the mitigation sites are more than 75% successful, we do not see a reason for abandonment of the existing mitigation sites and experimentation on other sites which may or may not have the same success rate.
6. Batiquitos Lagoon Foundation Letter Requesting the Following:
A. Traffic study: r
The City of Carlsbad's latest traffic count, which was compiled in April 1993,
indicates an Average Daily Trip (ADT) of 32,000. This traffic volume is three times
over and above the capacity of a two-lane road. The widening of this road is timely and necessary at this time. The ultimate traffic volume of La Costa Avenue at buildout with four (4) lanes is 37,000 vehicles per day. This traffic volume projection considers that all of the east/west arterial such as Poinsettia Lane,
Leucadia Boulevard, and Alga Road and Palomar Airport Road are constructed
to full-width. The existing traffic on La Costa Avenue exceeds the street capacity
and desperately needs to be widened.
6. Overall environmental impact of three phases of the project:
The original environmental report for La Costa Avenue, dated 1986, covered all three phases of the La Costa Avenue projects.
Phase I, which was the widening of the El Camino Real and La Costa Avenue intersection was completed in 1987. The required mitigation for Phases I, 11, and
111 were also installed in 1987.
Phase I1 is the proposed widening of La Costa Avenue from two to four lanes.
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U.S. ARMY CORPS OF ENGINEERS NOTICE NO. 93-868-EW
Phase 111 is the widening of the 1-5 overpass which is currently under design and
is 70% complete. Depending on the availability of funds, there is a fair chance that the road and bridge widening may be accomplished concurrently.
Inclusion of a Wildlife Corridor between Green Valley Riparian Habitat and the Lagoon: C.
The City has previously constructed three 8’ x 12’ concrete culverts at the Green
Valley crossing to carry 1 00-year flood, a fourth 8 ’x 12’ box culvert is proposed
to be constructed with the Phase II project. These culverts are dry most of the year, and sometimes several years at a time, and could well be utilized by animals
to cross from Green Valley to the north and into the lagoon marsh areas. In
addition, there are several large-size storm drains crossing the road at various
locations along La Costa Avenue that may be utilized by animals.
D. Onsite Construction Monitors During the Construction:
7.
The City of Carlsbad will stake all mitigation boundaries prior to construction and
will inform the contractor and City inspectors of its sensitivity. The City will not
allow any encroachment to these areas during the construction, since it is the
City’s responsibility to maintain these areas. The staking and delineation of the
mitigation sites is also a condition of the Coastal Development Permit.
Shoreline Study Center Letter
A. Noise Pollution: f
As previously indicated, the existing ADT on La Costa Avenue is rapidly approaching the ultimate traffic volume, and we believe that the existing noise
level will not be drastically altered by the addition of a few cars per hour.
8. Walls and Noise Level:
Contrary to the Shoreline Study Center’s belief, there are no retaining walls
proposed for this project. The City’s design for Phase II calls for inclusion of crib walls versus retaining walls. The City proposed the crib wall alternative to
minimize the impact to the natural look of the surrounding hills. In addition, the
proposed design includes planting and hydroseeding and irrigation of the crib walls with native species. Once these plants are established, the crib walls would blend into the surrounding slopes and it will be totally hidden from view. When established, the crib walls will have a similar impact on the noise reflection as the
existing natural slopes, which we believe will be negligible.
C. Status of Previously Implemented Mitigation:
This issue has been addressed in the answers given to the U.S. Fish & Wildlife service’s questionnaire.
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U.S. ARMY CORPS OF ENGINEERS NOTICE NO. 93-868-EW
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D. Timing of the Construction of Road and 1-5 Interchange:
As previously noted, the City will do its utmost to schedule and construct the two projects concurrently if funding permits.
In conclusion, it should be emphasized that the public and City’s concern in safeguarding the environment are the same and the City always is trying to have a balance between the environmental concerns and public safety. The City has done its utmost to minimize the impact
of this project to the natural habitats in and around Batiquitos Lagoon, and consistently has
sought advice and input from the public and permitting agencies to minimize any adverse
impacts to the environment.
Permits:
The City has received all required permits from Callfornla Coastal Commission and the California Department of Fish & Game and Mitigated Negative Declaration through the California Environmental Quality Act process for this project.
- We hope that the above responses satisfactorily address all the questions raised by the interested parties. However, If you believe that there are some questions unanswered or
inadvertently missed, please contact me at 438-1 161, extension 4385, to discuss and clarify any
items not properly addressed.
Once again, we appreciate your patience and close cooperation in processing this permit. We look forward to receiving the 404 Permit for this project at your earliest convenience. t c&F Project Manag
c: City Engineer Traffic Engineer Principal Civil Engineer, Walter Brown