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Home My WebLink About1999-01-12; City Council; 14986; Realignment Of Carlsbad Bl2 25 E % . . p 2 p z ’ CITY OF CARLSBAD -A&A BILL AB# /@ii m: DEPT. HD. MTG. PHASE I REPORT FOR THE REALIGNMENT OF CITY ATTY. @ ’ CARLSBAD BOULEVARD FROM MANZANO DRIVE TO DEPT. SAN MARCOS CREEK CITYMGR -+ RECOMMENDED ACTION: ACCEPT, by motion, the Phase I Report for the realignment of Carlsbad Boulevard from Manzano Drive to San Marcos Creek. ITEM EXPLANATION: In August 1998, the City hired Woodward-Clyde/URS Greiner to: 1) conduct an environmental constraints analysis for the Carlsbad Boulevard realignment study area and summarize those findings in a Phase I Report; and 2) prepare a corridor land use study to evaluate potential land use alternatives for the surplus public right-of-way created by the realignments. The study area includes all the public lands adjacent to Carlsbad Boulevard from Manzano Drive south to the bridge over the mouth of the Batiquitos Lagoon. The consultant has completed the Phase I Report which includes an environmental constraints inventory and preliminary impact analysis of the study area. Of the topics studied in this report no significant environmental constraint has been identified that would entirely preclude the realignment of the roadways and use of the surplus land. The major findings of this environmental constraints and opportunities analysis are summarized as follows: Geoloqv - Two geotechnical constraints (sea caves and liquefiable soil) have been identified that will require further study and specific treatment during any future project design phase. Neither of these issues pose a significant problem for future project development; Biolosy - The study area is highly disturbed and the only area with valuable biological resources is the Encinas Creek drainage. Impacts to the creek and adjacent wetlands are expected to be minimal. No vernal pools were identified in the study area; Cultural Resources - One cultural resource site was identified in the study area and will require further evaluation to determine its significance. Standard treatment and recovery methods will likely be sufficient to mitigate any impacts to this site. Two bridges located in the study area were constructed in the 1920’s and may be historically significant. Further evaluation of the historical significance of these bridges is recommended if they are impacted by a future project; Paleontolow - No previously recorded paleontologic sites have been identified within the study area. Monitoring for paleontologic resources during grading of geologic formations with the potential to yield fossils should be considered; Acoustics - Noise levels will increase 0 to 2 decibels on the east side of the northbound lanes of Carlsbad Boulevard, and decrease a similar amount on the west side of the southbound lanes. The City’s exterior noise standard of 60 CNEL dBA is currently exceeded at the Solamar Mobile Home Park due to existing traffic noise along Carlsbad Boulevard. The realignment of the southbound lanes of Carlsbad Boulevard will exacerbate this situation by approximately 1 to 2 CNEL dBA; and, Visual Quality - Because of the proximity of Carlsbad Boulevard to the coast and open vistas to the east, public views from Carlsbad Boulevard are extremely valuable. As part of any future projects, careful use of appropriate landscaping, design guidelines, building placement, and grading of bluff tops will be necessary to meet the visual quality goals and objectives of the City’s General Plan and Local Coastal Program. I PAGE 2 OF AGENDAiLL NO. /+ ffb Additional tasks completed in Phase I of the study include: the creation of a base map of the study area; calculation of surplus acreage and ownership; and mapping of constraints utilizing the Geographic Information Systems (GIS) data base created for the study area. Phase II in the study entails an analysis of the viable land use alternatives for the surplus vacant land based on the environmental impacts and existing physical constraints of the right-of-way area. The consultant and City staff will participate in a public agency and citizen involvement program to answer questions about the study and to obtain public input on potential land uses. The program will include a formal public community meeting along with informal presentations for stakeholder groups. An important question in this next phase of the study is whether there are economically viable land use alternatives that would provide sufficient revenue to help fund the construction costs of the roadway realignment. ENVIRONMENTAL REVIEW: No environmental review has been completed on the Phase I Report which is part of the larger planning study for the realignment proposal. The California Environmental Quality Act (CEQA) does not require environmental review for planning feasibility studies. However, prior to adoption of any project or land use change stemming from the recommendations of the study, detailed environmental analysis, in compliance with CEQA, will be required. FISCAL IMPACT: In June 1998, the City Council executed a $193,655.00 consultant agreement contract with Woodward-Clyde/URS Greiner to prepare the realignment and land use feasibility study. The consultant’s preparation of the Phase I Report fulfills the first part of their contract obligation at a cost of $59,240.00. EXHIBITS: 1. Phase I Report for the Realignment of Carlsbad Boulevard from Manzano Drive to San Marcos Creek (previously distributed - copies are on file with the City Clerk, Library, and Community Development). - -- PHA’sE I - OPPORTUNIT,ES AND CONSTRAINTS FINAL REPORT CARLSBAD BOULEVARD REALIGNMENT STUDY Prepared for City of Carlsbad Planning Department 2075 Las Palmas Drive Carlsbad. CA 92009- 1576 Woodward-Clyde Project No. 9853003K- 1.1 I December 7, 1998 Pacific Center II, Suite 1000 1615 Murray Canyon Road San Diego, CA 92108-4314 61 g-294-9400 Fax: 61 g-293-7920 - . - TABLE OF CONTENTS Executive Summary ..~........~.............................~.....~~.~~~~...~~~~~...~~~~..~..~........................~~.,.....~..........~.....~. ES-1 Section 1 Introduction .................................................................................................................... l-l Section 2 Section 3 Section 4 Section 5 ES- 1 Background ........................................................................................... ES-l ES-2 Major Findings ...................................................................................... ES- 1 1.1 Project History.. ........................................................................................ 1- 1 1.2 Project Description.. ................................................................................. l-2 1.3 Environmental Setting.. ............................................................................ l-2 Phase I Goals and Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*....... 2-1 Phase I Findings . . . . . . . . . . . . . ..I...................................,,..,..,.....................,,,.......................... 3-1 3.1 3.2 3.3 3.4 Environmental Issues ............................................................................... 3- 1 3.1.1 Geologic, Geotechnical, and Coastal Issues .............................. 3-l 3.1.2 Biology.. ................................................................................... .3-8 3.1.3 Cultural Resources ................................................................... .3-8 3.1.4 Paleontology .............................................................................. 3-9 3.1.5 Acoustics.. .............................................................................. .3-10 3.1.6 Visual Quality.. ....................................................................... .3- 13 Surplus Land Acreage and Ownership Inventory.. ................................ .3-14 Permits and Regulatory Approvals.. ...................................................... .3- 14 Cost Estimates ....................................................................................... .3-16 Conclusions ..I................I................................................................................................ 4-1 4.1 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4- 1 References ,..,................................,.,.,.,,..,.,,,..~.,,,,.......~................................................... 5-l -0 W:\9853003K\1-11-C-R.DOCW-Dec-99\SD i list of Tables and Figures Tables Table 3. l-l Table 3.1.1-1 Table 3.1.4-1 Table 3.2-l Table 3.4- 1 Figures Figure 1.1-1 Figure 1.1-2 Figure 3.1.1-1 Figure 3.1.1-2 Figure 3,1.2- 1 Figure 3.1.2-2 Figure 3.1.3-1 Figure 3.1.3-2 Figure 3.1.5-1 Figure 3.1.5-2 Figure 3.1.6- 1 Figure 3.1.6-2 Figure 3.2-l Figure 3.2-2 Summary of Potential Impacts and Measures to Reduce Impacts ................ .3-2 Recommended Minimum Safety Factors ..................................................... .3 -6 Paleontological Sensitivity of Geologic Formations in the Project Area ............................................................................................. .3- 10 Land Ownership and Amount of Land Available Following Realignment of Carlsbad Boulevard .......................................................... .3- 14 Estimated Construction Costs ................................................................... .3- 17 Regional Location Map Project Location Map Geology - North Geology - South Biology - North Biology - South Cultural Resources - North Cultural Resources - South Acoustics - North Acoustics - South Visual - North Visual - South Surplus Land - North Surplus Land - South - -w W:\9953003K\l-1 l-C-R.DOC\4-Dec-98\SDG ii Executhw Summan ES-1 BACKGROUND The proposed project consists of relocating the southbound lanes of Carlsbad Boulevard eastward to maximize the amount of public land available for other uses. Another aspect of the proposed project is the reconfiguration of Carlsbad Boulevard and Palomar Airport Road into a “T” intersection. The combination of relocating Carlsbad Boulevard and Palomar Airport Road would create large parcels of land located adjacent to the existing South Carlsbad Sate Beach campground and the coastline. This land could then be used for other purposes. The City developed a conceptual eastern alignment for Carlsbad Boulevard, and in 1997, directed staff to proceed with a study of the realignment of Carlsbad Boulevard from Manzano Drive to Batiquitos Lagoon (City of Carlsbad, 1997). In early 1998, the City selected Woodward-Clyde International Americas to conduct a study of the environmental constraints and opportunities created by the realignment of Carlsbad Boulevard and Palomar Airport Road (City of Carlsbad, 1998). This report presents the results of the environmental constraints and opportunities study. ES-2 MAJOR FINDINGS The findings of this environmental constraints and opportunities study are as follows: Of the topics studied in this report, no significant environmental constraint has been identified that would preclude the project from being constructed. Two geotechnical constraints (sea caves and liquefiable soils) have been identified that will require further study and specific treatment during the design phase of the project. Neither of these issues pose a significant problem for project development. The project area is highly disturbed and the only area with valuable biological resources is the Encinas Creek drainage. Impacts to the creek and adjacent wetlands are expected to be minimal and would not pose any unusual restrictions or permitting problems with regulatory agencies. One cultural resource site will require further evaluation to determine its significance. Standard treatment and recovery methods will likely be sufficient to mitigate any impacts to this site from the project. Two bridges located across Encinas Creek on the southbound lanes of Carlsbad Boulevard were built in 1928 and may be historically significant. Further evaluation of the historical significance of these bridges is recommended if they are deemed to be a part of the overall project. No previously recorded paleontologic sites have been identified within the project area. Monitoring for paleontologic resources during grading of geologic formations with the potential to yield fossils should be considered. Noise levels will increase from 0 to 2 decibels on the east side of the northbound lanes of Carlsbad Boulevard, and decrease by a similar amount on the west side of the southbound lanes of Carlsbad Boulevard. The City’s exterior noise standard may be exceeded at the Solamar Mobile Home Park due to the expected increases in traffic and along Carlsbad -0 w:\9853003K\1-1 l-C-R.DOCt4-Dec-98\SDG ES- 1 r r r r I- * r 1. Executh~e Summanr Boulevard. The realignment of the southbound lanes of Carlsbad Boulevard will contribute to, but not cause, this standard to be exceeded. Mitigation of the traffic noise to meet City standards can easily be achieved. * Because of its proximity to the coast and open vistas to the east, views from Carlsbad Boulevard are extremely valuable. As the project progresses, careful use of appropriate landscaping, design guidelines, and grading of bluff tops will be necessary to meet the visual quality goals and objectives of the City of Carlsbad General Plan. -0 w:\9853oo3KIl-1 1.C-A.DOCU-Dec.WSDG ES-2 - . ,- - - The City developed a conceptual eastern alignment for Carlsbad Boulevard, and in 1997, directed staff to proceed with a study of the realignment of Carlsbad Boulevard from Manzano Drive to Batiquitos Lagoon (City of Carlsbad, 1997). In early 1998, the City selected Woodward-Clyde International Americas (WCIA) to conduct a study of the environmental constraints and opportunities created by the realignment of Carlsbad Boulevard and Palomar Airport Road (City of Carlsbad, 1998). The goals of the study are as follows: 1. 2. 3. 4. A determination of the potential environmental impacts of the roadway realignments, and an inventory of the environmental constraints and opportunities in the study area; A technical evaluation of alternative land uses for the surplus land, based on the following priorities and objectives: a. Create and maintain open space recreational opportunities in the study area as the number one priority; and b. Land use should, where feasible, minimize impacts to environmental resources and the scenic qualities of the roadway corridor. An evaluation of the potential for revenue generating recreational/tourist serving commercial land uses in the study area to fund the realignment of the roadway and to develop recreational land use opportunities; A resource to: (a) allow staff and the City Council to more effectively evaluate and weigh the positives, negatives, and trade-offs of multiple land use planning opportunities along the roadway corridor; (b) facilitate input from affected public agencies and interested citizens; (c) provide the necessary technical expertise; and (d) help coordinate the land use evaluation process. - - 1.1 PROJECT HISTORY Beginning in the early 1980’s, the City of Carlsbad (the City) and the State Department of Parks and Recreation (the State) began to explore a program to relocate Carlsbad Boulevard to the east from Manzano Drive to San Marcos Creek (see Figures 1. l- 1 and 1.1-2). Initial planning for that program was incorporated into the South Carlsbad State Beach General Plan adopted by the State of California in 1982. The 1982 plan proposed that all additional property to the west of the realigned Carlsbad Boulevard would be dedicated to various recreational purposes, including additional camp sites, parking, beach access, and State administration and maintenance facilities. A major feature of this plan was a group camp site and hostel on property owned by the State between Manzano Drive and Palomar Airport Road. This plan anticipated that Palomar Airport Road would be realigned to a “T” intersection with Carlsbad Boulevard. Only limited progress toward implementation of the plan has occurred to date. The City commissioned a study of the realignment of Carlsbad Boulevard and Palomar Airport Road in the early 1990’s (Boyle Engineering Corporation, 1992). Key issues evaluated in the study included the irregular angle created where Palomar Airport Road joins Carlsbad Boulevard, vertical alignments, and the feasibility of salvaging the existing railroad bridge just west of Avenida Encinas. The study concluded that it was not cost effective to salvage the existing bridge and recommended an alternative that would minimize the skew of the intersection. -0 w:\9953003K\l-11 -C-d.DOCJ4-Dec-98\SDG l-l ‘/ - - - - !- i SECTIOWONE lntroductlon 1.2 PROJECT DESCRIPTION The study area includes all the public lands adjacent to an approximately 3-mile-long segment of Carlsbad Boulevard from Manzano Drive south to the bridge over the mouth of Batiquitos Lagoon (Figure 1.1-2). The north and southbound lanes of Carlsbad Boulevard are currently located in an approximately 200- to 350-foot-wide City-owned right-of-way. The north and southbound lanes are separated from each other by a distance ranging from approximately 40 feet to over 250 feet in some locations. This wide public right-of-way and road separation results in areas of vacant land located between and adjacent to the travel lanes. Therefore, the proposed project consists of relocating the southbound lanes eastward to maximize the amount of public land available for other uses. Another aspect of the proposed project is the reconfiguration of Carlsbad Boulevard and Palomar Airport Road into a “T” intersection. The combination of relocating Carlsbad Boulevard and Palomar Airport Road would create large parcels of land located adjacent to the existing South Carlsbad Sate Beach campground and the coastline. This land could then be used for other purposes. 1.3 ENVIRONMENTAL SElllNG The project area is bounded generally by Manzano Drive to the north, the bridge over Batiquitos Lagoon to the south, the Pacific Ocean to the west, and the Atchison Topeka and Santa Fe railroad to the east. The project area is located on the coastal bluffs that form the western boundary of the City. Elevations in the project area range from sea level to approximately 80 feet above sea level. Topography in the project area is relatively level, except in the vicinity of Encinas Creek where the roadway traverses the floodplain of this intermittent creek. Here, the roadway gently slopes from the coastal terrace to the floodplain and is located approximately 10 feet above sea level. Undeveloped areas within the project area are dominated by non-native vegetation consisting primarily of ice plant in the median and some bluff top areas, other weedy invasive species, scattered Cypress trees, and ornamental landscaping. Native vegetation is present in the vicinity of the Encinas Creek floodplain channel located east of the northbound lane. Riparian scrub, freshwater marsh, and other natural habitats are present in this location. Residential neighborhoods in the project area include Terra Mar north of Manzano Drive, Solamar Mobile Home Park immediately south of the Palomar Airport Road-Carlsbad Boulevard interchange, and the Lanakai Lane Mobile Home Park adjacent to Ponto Drive north of Poinsettia Lane. Other scattered residences are located south of Poinsettia Lane on Ponto Road. South Carlsbad State Beach is located north and south of Poinsettia Lane, west of the southbound lanes of Carlsbad Boulevard. -0 W:\9853003K\1-11-C-R.DOC\4-Dec-98\SD 1-2 .I; ‘. SAN BMNAkDlNO COUNM RIVERSIDE COUNTY SAN DIEGO COUNTY CARLSBAD BOULEVARD REALIGNMENT STUDY REGIONAL LOCATION MAP i.. r .I - . - - - SECTIONTWO PhaseIloalsandObiecthfes The goals and objectives of Phase I of the study are to conduct an environmental constraints inventory and preliminary impact analysis of the project area in the following areas: l Geology l Biology l Cultural Resources l Paleontology l Acoustics l Visual Quality. Additional tasks completed in Phase I of the study include the creation of a base map of the project area; calculation of surplus land acreage and ownership; and mapping of constraints utilizing the Geographic Information Systems (GE) data base created for the project area. The Phase I Report will assist the City to assess the viability of the project from a physical and environmental constraints standpoint. If the City decides to proceed with the study, then Phase II will be initiated and land use alternatives and economic feasibility of the project will be evaluated. -0 w:\9853003K\1-11 -C-R.DOC\4-Dee98\SDG 2-l 3.1 ENVIRONMENTAL ISSUES .- A description of existing conditions within the study area is presented in this section. In addition, the impacts of the project upon the environment is also discussed and measures to lessen these impacts are described. The topics discussed include those outlined in Section 2. A summary of the potential impacts from the project on these topics and measures that could be employed to reduce the impacts is presented in Table 3.1- 1. 3.1 .l Geologic, Geotechnical, and Coastal Issues 3.7.1.7 Field Reconnaissance - c- An engineering geologist and a geotechnical engineer performed a preliminary field reconnaissance along the project alignment on August 4, 1998. In addition, existing topographic maps, aerial photographs, published geologic information, and WCIA project files were reviewed. 3.7.7.2 Geologic Setting The site is located along an approximately 3-mile-long strip of the coastal plain starting just north of Batiquitos Lagoon. The project area geology is shown on Figures 3.1. l-l and 3.1.1-2. The majority of the existing roadway and the proposed realignment areas are underlain by Quaternary-age terrace deposits. Lesser portions of the alignment are underlain by localized placed fill soils. The alignment crosses one significant alluvial drainage named Encinas Creek (Figure 3.1.1-l). Underlying the terrace deposits are Tertiary aged sedimentary units that are exposed in the lower part of the seacliffs west of the road alignment. Brief descriptions of these geologic units are presented below (Tan, 1986). 3.1.1.2.1 Fill Road construction has resulted in shallow placed fills that are generally not extensive laterally or vertically. The existing Palomar Airport Road and Carlsbad Boulevard interchange may contain the most significant thickness of fill soils within the road alignment (Figure 3.1.1-1). Placed fill soils are also present in the existing Carlsbad Boulevard embankments that cross Encinas Creek (Figure 3.1. l-l). It is also likely that some minor fill soils are present in the approach embankments for the existing un-named overpass just north of Batiquitos Lagoon at Station No. 26800 (Figure 3.1.1-2). Fill soils have likely been derived from the adjacent terrace deposits and are probably relatively sandy in composition with a moderate fine-grained fraction. Localized areas of shallow to moderate depth fill soils may be present within the alignment due to original road construction but have not been identified at this time. -0 W:\9853003K\l-ll-C-R.DOC\4-Dec-98\Sffi 3-i - SECTIONTHREE i- ___ - I-. ?- - - .- Table 3.1-1 SUMMARY OF POTENTIAL IMPACTS AND MEASURES TO REDUCE IMPACTS Carlsbad Boulevard. Alluvial soils associated with the Encinas Creek minimize the impact of the sea caves on the project. A detailed geotechnical investigation will provide recommended measures to mitigate liquefaction and settlement issues. Examples of measures that could be employed include stone columns, compaction grouting, overexcavation and recompaction, deep dynamic compaction, and preloading with earthen other waters of the United States would be impacted by the realignment of the southbound lanes of Carlsbad Boulevard at Station No. practices during construction will likely be necessary. The project will require a Section 404 Permit (Nationwide No. 14) from the U.S. Army Corps of Engineers, a Section 401 Water Quality Certification form the Regional Water Quality Control Board, and a increase noise levels east of the northbound noise levels at all but one modeled residential lanes of Carlsbad Boulevard by 0 to 2 decibels, and reduce noise levels by an equivalent amount to the west of the southbound lanes of Carlsbad Noise modeling has indicated that at one The expected increase in noise that would cause an location at the southern end of the Solamar exceedance of the City of Carlsbad’s exterior noise neighborhood traffic noise could exceed the City standard can be reduced using standard noise of Carlsbad’s exterior noise standard of 60 dBA mitigation techniques. Specific noise mitigation CNEL. However, this noise standard would be should be designed when the project elevation is exceeded regardless of the proposed project due further defined. to projected increases in traffic. Noise generated during construction could annoy Adherence to the City of Carlsbad Municipal Code nearby residents. Section 8.48 regarding noise generated during construction should be adequate to minimize noise to acceptable levels during construction. Visual Quality No significant impacts to visual quality from the Careful consideration of landscaping, architectural currently proposed project have been identified. massing, and land use should be incorporated into the project as design progresses. - -0 W:\9853M)3K\l-ll-C-R.DOC\4-Dec-9B\SD 3-2 SECTIONTHREE 3.1.1.2.2 Alluvium The alluvial channel at Encinas Creek in the north-central portion of the road alignment is on the order of 400 to 600 feet in width (Figure 3.1.1- 1). Alluvial materials in this area are likely to be composed of coarse to fine-grained ranging from sand to silt and clay. There is a limited potential for gravel and cobbles. The depth of the alluvial deposits is not known. However, alluvium within major coastal drainages can be over 100 feet in depth. A relatively minor drainage such as Encinas Creek could have alluvial soils extend to depths of 50 feet or more. Loose, saturated, sandy alluvial soils may have a significant potential for earthquake-induced liquefaction and lateral spreading. Likewise, soft saturated fine-grained alluvial soils may be subject to significant consolidation settlement due to placement of new embankment fill overburden loads. - - - 3.1 .1.2.3 Quaternaty Terrace Deposits There are two Quatemary-age terrace deposit surfaces within the project area. The younger lower terrace deposit is not a widespread geologic unit and has been mapped in the project area as extending from the coast to about 200 to 350 feet inland. It is basically notched into the older higher terrace along the easterly edge of the existing north bound lane of Carlsbad Boulevard. The older higher terrace deposit is a much more extensive geologic unit in the coastal strip east of Carlsbad Boulevard. The two terraces are recognizable geomorphically and topographically. However, in terms of material types and engineering properties, they are essentially identical. As a result, mapped terrace deposits are described as a single geologic unit. The upper portion of the terrace deposits contain a reddish brown silty to clayey sand to sandy lean clay soil horizon which grades with depth into predominately sandy materials. The lowermost portion of the terrace deposits commonly contain a thin layer of marine sand overlying the contact with the Tertiary sedimentary bedrock. In general, the terrace deposits are highly erodible. The use of excess terrace deposits for beach nourishment fill is discussed in Section 3.1.7. 3.1.1.2.4 Tertiary Sedimentary Bedrock The bedrock units underlying the terrace deposits are Eocene-age marine and nonmarine deposits. The mapped geologic formations in the area include the undifferentiated Friars/Delmar Formation (Eisenberg, 1986), the Scripps Formation and the Santiago Formation (Tan, 1986). Based on review of existing geologic mapping, there is not a consensus on which bedrock units are present in the area. In general, all these units are composed of interbedded sedimentary deposits ranging from siltstones and claystones to sandstones. The exposures along the northern portion of the alignment are composed of primarily sandstones. 3.7.7.3 Geofechnical Considerations Generalized geotechnical considerations are presented below for 4 reaches of the proposed project alignment (Figures 3.1.1-I and 3.1.1-2). -0 W:\9853033K\l-1 l-C-R.DOC\4-Dec-98\SDG 3-3 - .- r - - - Station Nos. 37000 to 39800 This reach includes the rerouting of Palomar Airport road and includes an area sensitive to coastal bluff retreat. Faults and fractures in the sedimentary bedrock have promoted erosion into the bluff resulting in the formation of 3 small to medium sized sea caves (Figure 3.1.1-1). These sea caves and associated blufftop development are further discussed in Section 3.1.4. In addition, in this reach the rerouting of Palomar Airport Road may include removal of existing embankments and bridges, construction of a new level intersection, and possibly the modification of the existing Palomar Airport Road bridge over the railroad. Final road grades and widths in this area will dictate whether or not the railroad overpass will need to be redesigned or replaced. The open project area north of Palomar Airport Road is relatively flat and considered suitable for conventional land development. Station Nos. 33000 to 37000 This reach contains the Encinas Creek alluvial drainage crossing that contains potentially liquefiable and compressible soils. Appropriate subsurface investigations will be necessary to evaluate the embankment crossing and present appropriate mitigation measures. Possible ground improvement measures are discussed in Section 3.1.5. All other areas of this reach may be considered stable and suitable for conventional road construction. Station Nos. 28000 to 33000 Only minor topographic changes are envisioned for this reach as a result of the proposed road realignment. The reach is underlain terrace deposits and minor fills associated with existing road improvement. This reach contains no major design issues from a geotechnical perspective and may be considered stable and suitable for conventional road construction. Station Nos. 25000 to 28000 Road improvements in this reach may include some minor grading. The easterly realignment of the roadway will result in some cuts along the southern portion of this reach since the alignment rises in elevation out of the Batiquitos Lagoon drainage area. An existing small bridge and drainage culvert near Station No. 26800 will likely be modified. Positive drainage control and potentially significant cuts and fills are the primary geotechnical issues in this reach. This reach contains no other major design issues from a geotechnical perspective and may be considered stable and suitable for conventional road construction. 3.7.1.4 Sea Caves and Bhfftop Development Other than conventional stable engineered cut and fill slopes which would be part of overall earthwork and grading of the proposed realignment project, the only significant area of concern for blufftop geologic stability is near Station No. 39400. The existing setback distance from the blufftop to Carlsbad Boulevard is less than 10 feet in this location. Specifically, in this area the adjacent shoreline has undergone severe beach erosion and landward retreat of the blufftop to the ,- -0 w:\9853003K\l-1 l-C-R.DOC\4-Dec-98\SDG 3-4 ,- . SECTIOWTHREE - - - extent that faults and fractures in the sedimentary bedrock have promoted the formation of 3 relatively small to medium sized sea caves. 3.1 .1.4.1 Sea Cave Mitigation The formation of sea caves is a complex geomorphic process which is controlled by weathering and wave abrasion in the fractured material. The initial formation of a sea cave by hydrostatic and hydrodynamic erosive attack of existing fractures is followed by collapse of the cave and the formation of a recess or re-entrant into the coastline. Expansion of the sea cave is accelerated by landward progression of focused hydrodynamic energy during periods of high tide and high wave conditions in this location. Successive or episodic sea cave roof collapses and differential bedrock conditions on either side of the sea caves have allowed the formation of a re-entrant shoreline which is fairly common along this stretch of coast. The relative erosion rate for a developing sea cave near a re-entrant section of shoreline may be expected to be significantly greater than the average erosion rate along a nearly linear section of shoreline. - -- A possible mitigation method includes filling the sea cave with concrete. The sea cave filling should be consistent with design and construction with similar previously approved sea cave fillings in North County such as those in De1 Mar, Solana Beach, Encinitas, and Carlsbad. The filling of the sea caves should have a retarding effect on the localized erosion rate but may not affect the overall rate of erosion in the area. The concrete should be a moderate strength sulfate resistant mix, be colored to match color of existing bluffs, and sufficiently inset into bedrock in its foundation, both sides, and roof (if possible). It may be possible to incorporate remedial blufftop grading or a beach access stairway in this location, if desired. Alternatively, the proposed road realignment may be sited further to the east to avoid encroachment into the blufftop area. r - 3.1 .1.4.2 Shoreline Erosion and Setbacks The California Coastal Commission requires that blufftop development be sited and designed to assure stability and structural integrity while minimizing alteration to natural land form (California Coastal Commission, 1981). Blufftop development should not be allowed to create or contribute to problems of erosion or geologic instability. Filled sea caves and blufftop retaining structures may only be allowed to “check” marine erosion when there is no less environmentally-damaging alternative. In this respect, if blufftop development is planned, then a geotechnical investigation will be required. The investigation should evaluate bluff stability and the means to minimize geologic hazards. In addition, the geotechnical investigation should address development alternatives and design requirements. - Relative shoreline erosion rates for Tertiary bedrock differs throughout North County. Many shoreline researchers have addressed this issue and have estimated widely varying rates of shoreline retreat (CDBW and SANDAG, 1994). However, an estimated average erosion rate of 0.2 to 0.5 feet per year may be considered reasonable for the project area if a wide protective sandy beach is not present. Consequently, shoreline retreat of 2 to 5 feet may be possible in a 10 year period. Much of the observed erosion occurs during combined high tide and storm wave -0 W:\9853003K\l-1 I-C-R.DCC&Dee-98SDG 3-5 -- .- -- --~ - r-- c ! ,--- _- -- conditions. Therefore, predicting erosion rates is very difficult. The regional erosion rate can be assumed to be episodic with extreme periods of rapid degradation (SANDAG, 1993). Lf the sea caves are stabilized by proper infilling with a nominal amount of concrete, then an appropriate setback from the blufftop may be assumed to be on the order of 50 feet from the existing blufftop edge. This distance may be refined based on a site specific slope stability evaluation. However, if a substantial sea cave filling is engineered and constructed with an elevated blufftop retention system, then the setback distance may be significantly reduced. This alternative would involve substantial slope reconstruction and feathered transition fills north and south of the sea caves. Conversely, if the sea caves are not mitigated, the recommended setback could be on the order of 50 feet plus 0.5 feet for every year the realigned road is intended to be in service (i.e., 75 feet for a 50-year design life). 3.1.1.4.3 Slope Stability In general, the inland portions of the realignment project area may be categorized as being only marginally susceptible to landslides and slope instability. These areas are relatively competent and underlain with relatively stable level ground. However, oversteepened cut slopes in such materials should be engineered to have stable inclinations. On the other hand, the majority of blufftop areas along the shoreline may be considered to be susceptible to erosion, undermining, and bluff instability. In general, potentially unstable bluff areas may be assumed to be immediately adjacent to the shoreline high bluff coastal strip throughout the project area (Figures 3.1. l-l and 3.1.1-2). These steep and high bluff areas may be underlain by geologic materials having relatively weak clay seams at the basal contact of the terrace deposits. Geotechnical investigations should be performed to evaluate landslide susceptibility of bluff areas that may impact the proposed road alignment. Recommended minimum safety factors for slopes are presented in Table 3.1. l- 1. Table 3.1.1-1 RECOMMENDED MINIMUM SAFETY FACTORS Condition Temporary Static or Dynamic Static Minimum Safety Factor 1.2 Permanent Permanent Static Dynamic For the purpose of initial slope stability analyses, it may be assumed that a pseudo static ground acceleration of 0.2 g may be used for dynamic analyses of permanent slopes. This value may be considered approximately r/z of the deterministic peak ground acceleration for the project area. However, an appropriate engineering analyses and selection of the parameters should be evaluated during design. -0 W:\9853003K\l-ll-C-R.DOCLI-Dec-98\SD 3-6 ,- - ^ I-- r c- -- - SECTIONTHREE 3.1.1.5 Alluvial Sediments The only other area of the proposed road alignment that may have an exposure to potential geologic hazards is the alluvial drainage associated with Encinas Creek between Station Nos. 34900 and 35600 (Figure 3.1.1-l). Alluvial soils in this area are likely to be poorly consolidated sands and fine-grained material having relatively low density, a shallow groundwater table, and moderately high compressibility. In general, loose sandy materials in this area may be considered moderately susceptible to earthquake induced soil liquefaction. A resultant effect of soils liquefaction may include significant ground settlement and lateral spreading due to unbalanced embankment loading conditions. In addition, fine-grained alluvial soils may be susceptible to moderate consolidation settlement due to placement of embankment fill loads greater than 5 feet. The project geotechnical investigation should address the means and methods to mitigate both the effect of liquefaction and consolidation settlement. Possible ground improvement mitigation measures that may be considered are stone columns, compaction grouting, overexcavation and recompaction, deep dynamic compaction, and preloading with earthen surcharges. Bridge or culvert construction may be possible with either conventional spread footings or pile/pier foundations. 3.1.7.6 Faulting Based on a review of available information and a site reconnaissance, there does not appear to be any type of faulting in Tertiary sediments of the project area other than what has been previously described for the known sea caves (Sections 3.1.3 and 3.1.4). There does appear to be some localized fracturing and faulting along the shoreline bluff areas south of Batiquitos Lagoon in the Leucadia area of Encinitas. In addition, several fault exposures have been identified in hillsides south of Batiquitos Lagoon adjacent to La Costa Avenue and several miles up stream of Encinas Creek. However, these faults and fractures do not impact the study area. 3.1.1.7 Beach /Voufishment The City may wish to utilize excess excavated blufftop terrace deposits as beach nourishment fill material. In general, the terrace deposits are relatively sandy with typically less than 20 percent fine-grained material (passing the No. 200 sieve). These materials may be considered well suited for beach nourishment fill if placed at designated and approved feeder beach locations (Moffatt & Nichol Engineers, 1998). A logical feeder beach location would be at the mouth of Encinas Creek (Sherman, 1998). Sand placement at feeder beach locations is conventionally performed during low tide conditions such that sand can be dumped and spread on the exposed nearshore. The incoming tide and associated surf creates a mixing and dispersion of the sand and fine- grained materials such that the littoral current transports the sand down coast and fine-grained material further offshore. Terrace deposits in the project area are typically tan to reddish brown in color. These materials contrast with the normal light to dark gray beach sands found along the shoreline. However, if excess terrace deposits are found that are relatively free of fine-grained material (less than 2 7 -0 w:\9853003K\l-1 l-C-RDOCW-Dee99\SDG 3-7 /- . - rc- .- i- * ,- r- r percent passing No. 200 sieve) and are very light in overall color, then consideration should be given to using these materials for direct placement as beach nourishment fill. 3.1.2 Biology A biological resources report has been prepared for the proposed project (WCIA, 1998a). The following is a summary of the report. The proposed project would result in realignment of lanes of Carlsbad Boulevard through land that is generally highly disturbed and that does not support natural biological communities (Figures 3.1.2-I and 3.1.2-2). Most of this disturbed land is dominated by iceplant, other ruderal (weedy) species and non-native grasses, or barren ground. No vernal pools were observed within the area that could be directly impacted by the project. One area of natural habitat occurs near Station No. 35000. This area consists of marshland on the east side of the northbound lane that is associated with Encinas Creek. The present project plan would not adversely affect this area. Encinas Creek passes under the present road lanes and supports a narrow highly disturbed aquatic habitat within the creek between the lanes. The project would result in extension of the existing culvert that covers the creek from the existing northbound lane. This culvert extension would not result in significant adverse effects on biological resources because this area is small and in a highly disturbed condition. Opportunities exist for potential expansion of habitats associated with Encinas Creek if the landform between the two existing lanes were lowered in elevation to the south of the creek. This type of habitat expansion is not considered to be necessary as no compensatory mitigation measures for adverse impacts on biological resources are expected to be required for this project. No potential adverse direct or indirect impacts on biological resources have been identified for this project. Overall impacts on biological resources from the proposed project are not expected to be significant or pose substantial issues during project permitting. Use of best management practices to minimize disturbance areas and control erosion from the site will ensure that areas such as the Pacific Ocean, Batiquitos Lagoon at the southern end of the project route (beyond the project boundary), and the wetland near Station No. 35000 are not adversely affected. Permits that would be required for the project from Federal and State resource agencies are discussed at Section 3.3. 3.1.3 Cultural Resources A cultural resource survey for the proposed project was completed (Gallegos & Associates, 1998). The following is a summary of the survey. Only two previously recorded cultural resources (CA-SDI-760 and SDM-W-111) were identified within the study area by the literature review and record search (Figures 3.1.3-l and 3.1.3-2). Site CA-SDI-760 was not relocated and is believed to have been destroyed by previous development or is situated outside and east of the study area. Site SDM-W-111 was relocated during the field survey. This site is located on a bluff on the east side of Carlsbad Boulevard and south end of the Solamar Mobile Home Park. The west portion of the site has been disturbed by construction of existing Carlsbad Boulevard which has impacted the site by grading and construction of an earlier road alignment in the existing road separation. The site may extend east under the mobile home park. Cultural material noted includes shell, debitage, and a mano west of the frontage road and in the 7-- -0 W:\99853003K\l-ll-C-R.DOC\4-Dec-98\Sffi 3-8 - __- - -- I- - r- i /- landscaping. Testing to determine the size, integrity, and significance of SDM-W-111 within public lands is recommended during project permitting. In addition to the prehistoric site, portions of old Highway 101 will be impacted/affected by the proposed realignment project. Also, a number of the bridges have been assessed for significance by Caltrans and identified as not eligible for listing on the National Register of Historic Places. These bridges include bridge number 57CO176 spanning the railroad at Palomar Airport Road; bridge number 57CO215 referred to as the Las Encinas overcrossing at Palomar Airport Road; bridge number 57CO307 on the northbound lanes of Carlsbad Boulevard spanning Encinas Creek; and bridge number 57CO212 just south of Ponto Storage in the northbound lanes of Carlsbad Boulevard. Historic research, mapping and documentation of the old road is recommended during project permitting. For bridges (57CO214L and 57C0214R) associated with old Highway 101, an assessment of significance is recommended during project permitting. 3.1.4 Paleontology Carlsbad Boulevard traverses the coastal terrace and is underlain primarily by Quaternary aged terrace deposits (Figures 3.1. l-l and 3.1 .l-2). The terrace deposits are in turn, underlain by Tertiary-age sedimentary deposits. All of these geologic units are potentially fossiliferous. The geologic setting and the geologic units and their paleontological sensitivity are discussed in the following sections. For this investigation, the following geologic references have been reviewed: l Eisenburg, 1986, Pleistocene and Eocene Geology of the Encinitas and Ranch0 Santa Fe Quadrangles l Tan, 1986, Landslide hazards in the Encinitas Quadrangle, San Diego, California. In addition, Dr. George Kennedy, a paleontologist with San Diego State University was consulted regarding the paleontological resources in the area. Dr. Kennedy has reviewed the following paleontological collections in Southern California for possible fossil localities in the project vicinity: l San Diego State University l San Diego Museum of Natural History l Los Angeles County Museum of Natural History. Based on his preliminary review, there are no known fossil localities in the immediate project area. The nearest Pleistocene localities are recorded from around the north-central and eastern margins of Batiquitos Lagoon; none are recorded near the mouth of the lagoon. The nearest recorded locality of Eocene fossils is greater than 1 mile east of Carlsbad Boulevard along Palomar Airport Road. A discussion of potential paleontological resource sensitivity of the geological formations likely to be encountered in the project area is presented in Table 3.1.4- 1. -0 w:!9853003K\1-1 I-C-RDOCWDee99\SDG 3-9 - - .- - ,-- -. Table 3.1.4-1 PALEONTOLOGICAL SENSITIVITY OF GEOLOGIC FORMATIONS IN THE PROJECT AREA however, there may not be any significant impacts. The terrace deposits are not fossiliferous throughout the deposit. In fact, it is only the lowermost portion of the terrace deposits near the basal abrasion surface that contains marine deposits and localized abundant fossils. The overlying materials are nonmarine and are not generally fossiliferous and would not be considered highly sensitive. The project as proposed would not involve mass grading within the lower portion of the terrace deposits and would not impact the lower fossiliferous zone. In light of these conditions, it is suggested that monitoring be conducted on a part-time basis during basic grading operations, Project activities that could extend into the fossiliferous zone and require more monitoring would oundation excavations (bridge works) that extend into the lower portions of the terrace on structures if constructed as part of the project, wotlrd impact the Tertiary In general, the project as currently defined, is not likely to have any significant impacts to paleontological resources in the project area. However, some level of paleontological monitoring may be needed during construction because some of the underlying geologic formations have a medium to high degree of paleontologic sensitivity. Once the project has reached the design level, a monitoring and mitigation plan can be developed based on specific construction elements. 3.1.5 Acoustics An acoustics assessment for the proposed project was performed (WC& 1998b). The following is a summary of the assessment. 3.7.5.7 Project-Related Noise Existing and future traffic noise levels were modeled in order to compare potential effects of the project at noise sensitive receivers. Three scenarios were modeled: existing conditions (i.e., existing traffic volumes and existing roadway geometry); future with project (Year 2010 traffic volumes and proposed realigned roadway geometry) and future without project (Year 2010 traffic volumes and existing roadway geometry). - -0 W:\9953003K\1-11-C-R.DOCWDec-98\SDG 3-10 ,- - - _- !- - - ,- - - .- 7- - Noise levels from traffic along Carlsbad Boulevard and Palomar Airport Road are anticipated to increase in the future, either with or without the proposed project. Future without project traffic noise levels will generally increase by 2 to 3 decibels compared to existing noise levels. This increase is attributable to future increases in traffic volumes. For example, noise levels at residences in the Solamar neighborhood overlooking Carlsbad Boulevard would increase from 62 dBA CNEL in the existing case to 65 dBA CNEL in the future without project case. The realignment of Carlsbad Boulevard would result in noise level increases ranging from 0 to 2 decibels on the east side of the northbound lanes of Carlsbad Boulevard and corresponding decreases of 0 to 2 decibels on the west side of the southbound lanes of Carlsbad Boulevard. Land uses and locations of noise monitoring sites within the project study area are shown on Figures 3.1.5-l and 3.1 S-2. Along both sides of Carlsbad Boulevard, most of the receptors would experience changes in noise levels of approximately 1 decibel. Typically a change in noise level of 1 decibel is inaudible except under controlled (i.e., laboratory) conditions, while a change in noise level of 3 decibels is considered just perceptible. Noise levels at noise sensitive land uses along the east side of the project route would increase as a result of the proposed realignment of Carlsbad Boulevard. These noise increases would be relatively small and could be easily mitigated, if necessary. A range of potential noise abatement measures exist which could be utilized (if necessary) to reduce project noise to below City of Carlsbad standards. Such measures include construction of earthen berms, soundwalls, or building improvements such as window upgrades (i.e., dual-glazing). With the exception of one modeled location, representative of residences at the southern end of the Solamar Mobile Home Park, these increases would not cause an exceedance of City, State or Federal noise standards. At this location, the future with project noise level is expected to increase by 3 decibels compared to existing conditions. This increase would result in an exceedance of the City of Carlsbad’s exterior noise standard of 60 dBA CNEL. However, the noise standard at this location would be exceeded either with or without the proposed project; the project would contribute approximately 1 decibel to the future noise level. It should be noted that the noise modeling for this feasibility analysis was conducted using preliminary project design information. The project’s alignment and elevation is expected to evolve as the project proceeds. Thus, subsequent noise analysis and design of mitigation measures, if needed, should be based upon refined design information. 3.1.5.2 Construction-RelatedNoise The proposed project would require the use of heavy equipment to grade and pave the roadways for a realigned Carlsbad Boulevard and to construct associated structures such as the curbs, gutters, and sidewalks. For a typical project of this size, a maximum of four to five pieces of heavy equipment at any one time would be required to perform these tasks. -0 W:!9B53003K\l-1 l-C-R.DOC\4-Dec-99\SDG 3-11 .- - t- - - i- c - - The evaluation of project construction noise impacts in this noise assessment is based on typical noise level ranges for construction sites (Bolt et al., 1971 for the Environmental Protection Agency). Average noise levels associated with various construction phases where all pertinent equipment is present and operating at a reference distance of 50 feet are: l Ground Clearing 84a6 dBA l Excavations 896 dBA l Foundations 78+3 dBA l Erection of Structures 85&5 dBA l Finishing (i.e., Paving) 896 dBA (Source: Bolt, et. al., 1971 for the Environmental Protection Agency). Because of vehicle technology improvements and more strict noise regulations enacted during the last 26 years, this analysis will use the minimum noise level shown above. This information indicates that the overall noise level generated on a construction site could approach 83 dBA at a distance of 50 feet. Noisy construction activities could be in progress on more than one part of the project site at a given time. This analysis accounts for the fact that the magnitude of construction noise levels varies over time because construction activity is intermittent and power demands on construction equipment (and resulting noise output) are cyclical. Noise levels generated by construction equipment (or by any “point source”) decrease at a rate of approximately 6 decibels (dB) per doubling of distance away from the source (Diehl, 1973). Therefore, at a distance of 100 feet the noise levels will be approximately 6 dB lower than at the 50 foot reference distance. The noise from construction activity, although short-term in nature, would be higher than measured and modeled ambient daytime noise levels at adjacent noise sensitive receivers and could result in annoyance of nearby residents unless measures are taken to lower construction noise levels. Except for construction equipment and material staging areas, construction activities and associated noise would move along the project route as construction of the project proceeded. In general, no single residence or noise-sensitive area would be subject to constant noise levels continuously for the duration of the project. The potential for high noise levels from construction activities is recognized in the City of Carlsbad’s Municipal Code Section 8.48. Section 8.48 contains conditions of approval which may be placed upon projects for which potential noise impacts have been identified. One such condition of approval is the requirement that all construction vehicles or equipment operated within 1,000 feet of a noise sensitive use shall be equipped with properly operating and maintained mufflers. Another condition of approval is that stockpiling and/or vehicle staging areas be located as far as practicable from noise sensitive uses. It is recommended that these and the other measures in Municipal Code Section 8.48 be utilized to minimize construction noise impacts at adjacent noise sensitive receivers. - -0 W:\9853003K\l-1 l-C-R.DOC\4-Dec-98\SDG 3-12 PhasaIFfndings 3.1.6 Visual Quality A visual quality assessment for the proposed project was completed (WRT, 1998). The following is a summary of the assessment. The landscape in the project area is currently perceived as open, in contrast to the townscape of Leucadia to the south and Carlsbad’s residential neighborhoods to the north. The adjacent land uses include the South Carlsbad State Beach Campground along the bluffs west of the southbound lanes of Carlsbad Boulevard, two mobile home parks east of the northbound lanes of Carlsbad Boulevard, small industrial properties in the Ponto area, and a timeshare resort east of the northbound lanes of Carlsbad Boulevard, south of Encinas Creek. Parking for beach access lies along the western portions of the southbound lanes of Carlsbad Boulevard in the low areas. Future development adjacent to the project area is expected to include residential and commercial uses oriented to recreationalists and travelers. - - ,- L - The State campground occupies huch of the bluff tops to the west of Carlsbad Boulevard. It is screened fairly well from views along the roadway with small, non-native evergreen trees. But, views to the ocean are also blocked by the vegetative screen, campers, and tents. As a result, the visual experience along the bluff top portions of Carlsbad Boulevard is contained within the corridor. In contrast, where Carlsbad Boulevard passes into and through the low areas, the views are open to the horizon providing views to natural landscapes such as bluffs, beaches, and lagoons. These areas include the two valleys and at the interchange of Palomar Airport Road and Carlsbad Boulevard. The City of Carlsbad General Plan defines these sites as Special Resource Areas as they are of citywide or regional significance. /- The segment of Carlsbad Boulevard through the project area exhibits a character of wide-open spaces, accessible to many via the State campground, beach parking, and mobile home parks. It contrasts with the character north and south of the project area where private development is built-up on both sides of the road. - - C The General Plan prescribes tools to be employed to enhance visual quality throughout Carlsbad. Land use buffers are defined as areas “between land uses strengthen the perception of individual small communities within the city and to mark entries into neighborhoods and development”. Greenways are defined as “open space connectors linking parks, nature preserves, cultural features.. .in order to improve environmental quality and provide for outdoor recreation and enhance the visual perception of open space”. While Carlsbad Boulevard is not defined as a Greenway, many of the design parameters should be employed to improve the scenic quality of the corridor. . - Vegetation appropriately planted along the corridor can serve to both screen private development from the view at public places and frame the valuable views of the private property owners. The plant palette should consist of native species or species that are adapted to the coastal climate and will not spread into the areas of native habitat. Planting design should contribute to the visual diversity along the corridor. Additionally, openings in the vegetation screen at the State campground should be considered at key points such as at the intersections of Carlsbad Boulevard with Poinsettia Drive and Avenida Encinas. -0 W:\9953003K\l-ll-C-R.DOCW-Dec-98\SDG 3-13 - SECTIOWTHREE Phase I Flndings - - Development on the bluff tops should be carefully sited and screened to maintain the scenic quality of the area. Grading should be designed to positively direct views along the corridor. The use of fencing should be limited to short runs (less than 200 foot-length) to screen views of private development and until desirable vegetation is trained to cover the fencing. Finally, facilities and land uses must be designed and maintained to provide safe access to the resources without obstructing the prized views of the beaches and ocean. C 3.2 SURPLUS LAND ACREAGE AND OWNERSHIP INVENTORY A City-provided GIS parcel map was used in conjunction with a City-generated map showing land ownership in the project area to calculate land remaining after Carlsbad Boulevard is realigned. Additionally, the amount of land owned by the State in the area north of Palomar Airport Road and south of Manzano Drive was calculated. The land available following realignment of Carlsbad Boulevard is shown in Table 3.2-l. The amount of City-owned land available for other uses following realignment of Carlsbad Boulevard was calculated to be approximately 41 acres (Figures 3.2.1 and 3.2.2). This acreage differs slightly from the acreage calculated previously by the City (City of Carlsbad, 1997) due to the need for approximately 5 acres of land for a 2: 1 slope on the western side of the southbound lanes of Carlsbad Boulevard from Station No. 34800 to Station No. 37000. The amount of land owned by the State in the area north of Palomar Airport Road and south of Manzano Drive was calculated to be approximately 15 acres. Table 3.2-l LAND OWNERSHIP AND AMOUNT OF LAND AVAILABLE FOLLOWING REALIGNMENT OF CARLSBAD BOULEVARD ,-- 3.3 PERMITS AND REGULATORY APPROVALS This section provides an overview of the environmental permits and approvals likely to be required for the project. The permit and regulatory approvals listed are based on our experience permitting similar projects along the southern California Coast. This section focuses on environmental permits and does not evaluate other permits and approvals that may be required such as a Caltrans encroachment permit and approval from the Atchison Topeka and Santa Fe Railroad for a new bridge at Palomar Airport Road. -0 W:\9853003K\l-1 l-C-RDOC\4-Dec.98\SDG 3-14 Stream Alteration Agreement Permitting Agency: California Department of Fish and Game (CDFG) Pursuant to the California Fish and Game Code Section 1601, the City of Carlsbad would be required to enter into a Stream Alteration Agreement with CDFG for work that would affect Encinas Creek. In order to expedite the approval of this agreement, it is advisable to coordinate with CDFG during the environmental review phase of the project. This will allow CDFG concerns to be identified and, if warranted, changes made to project design to address the concerns. This up-front coordination will pave the way for CDFG processing of the 1601 agreement following Certification of the Final Environmental Impact Report (EIR). - - - - - - - ,- - ,- Clean Water Act Section 404 Permit Permitting Agency: United States Army Corps of Engineers (USACE) A Section 404 permit from the USACE for discharge of fill material into jurisdictional other waters of the United States (Encinas Creek) would be required. Authority for this permit is derived from Section 10 of the Federal Rivers and Harbors Act of 1899, Section 404 of the Clean Water Act, and Section 103 of the Marine Protection, Research, & Sanctuaries Act. It is anticipated that the project would meet the requirements of, and therefore be authorized by, the USACE Nationwide Permit 14, Road Crossings, and would not require pre-discharge notification. If the area of potential effect of the project includes jurisdictional wetlands, it is anticipated that Nationwide Permit 14 would also apply to this activity. This permit, or application to the USACE for concurrence that a Nationwide Permit will apply to the project, is typically applied for after the Final EIR is certified. As with the CDFG, it is also advisable to coordinate with the USACE prior to submission of an application or request for concurrence that a Nationwide Permit is applicable to the project. Clean Water Act Section 401 Water Quality Certification or Waiver Permitting Agency: Regional Water Quality Control Board (RWQCB) The Section 401 certification would be required for discharge of fill material into Encinas Creek. Authority for this permit is derived from Section 401 of the Clean Water Act. It is anticipated that a waiver would be granted within approximately 30 days of submittal to the RWQCB. A request for a waiver is typically sought concurrently with a Section 404 permit application. Amendment to the Local Coastal Plan Permitting Agency: California Coastal Commission The City of Carlsbad would be required to prepare and process an amendment to the City’s Local Coastal Plan as part of a Specific Plan for the project. Authority for this requirement is derived from the California Coastal Act of 1976. -0 W:\9853003K\l-1 l-C-R.DOCGI-Dec.98\SDG 3-15 - - - - r - - r SECTIOWTHREE California Environmental Quaky Act (CEQA) Compliance Lead Agency: City of Carlsbad The project will likely require and EIR to be prepared due to the sensitivity of any significant project proposed for development along the coast, as well as this specific project. Although no significant unmitigatable environmental impacts have been identified in this study, the public and agency interest and issues generated in the project would probably require that an EIR be prepared. Authority for this requirement is derived from California Public Resources Code 21000 et. seq. The time required to complete the CEQA process can vary depending on a variety of factors. In general, a project of this scope will require approximately 1 year to complete the CEQA process from selection of a contractor to certification of the Final EIR. National Environmental Policy Act (NEPA) Compliance If Federal funds are used for any portion of the project, the Federal agency providing funding would likely serve as the lead Federal agency for the NEPA review process. If NEPA compliance is required, a joint Environmental Impact Statement/Environmental Impact Report (EIWEIR) could be prepared. CEQA has provisions for preparing joint documents and the time to prepare a joint EIS/EIR would be approximately the same time required to prepare an EIR (i.e., 1 year). 3.4 COST ESTIMATES To analyze the project’s estimated construction costs, the project was divided into three general areas. These include the southbound lane realignment, the northbound lane realignment and the Palomar Airport RoadKarlsbad Boulevard intersection reconstruction. The southbound lane realignment consists of two new lanes on a new alignment (shifted from west to east) from approximately 500 feet north of the Batiquitos Lagoon bridge (Station No. 25000) to the north end of Solamar Mobile Home Park (Station No. 37200). The northbound lanes are realigned in discrete segments where adjacent development has not already encroached upon the Carlsbad Boulevard right-of-way. The northbound lane realignments occur in three locations: from Station Nos. 25400 to 27800, 28200 to 31800 and 33800 to 35600; these realignments consist of slight shifts in the alignment from west to east. The Palomar Airport RoadKarlsbad Boulevard intersection reconstruction extends from the north end of Solamar Mobile Home Park (Station No. 37200) to Manzano Drive (Station No. 39800) and along Palomar Airport Road to Avenida Encinas north of the railroad right-of-way. Table 3.4-l summarizes the estimated construction costs based upon the preliminary engineering layouts developed for the project studies. The costs appear to be relatively consistent with cost estimates included in previous studies for the realignment of Carlsbad Boulevard and the reconstruction of the Palomar Airport RoadKarlsbad Boulevard intersection (City of Carlsbad, 1997). -0 W:\9853003K\l-1 I-C-RDOC\4-Dee-99\SDG 3-16 - - SECTIONTHREE Table 3.4-l ESTIMATED CONSTRUCTION COSTS Southbound Realignment1 Northbound Realignment2 PAFUCarlsbad Intersection3 Subtotal I $ 11,528,OOO Continaencv (30%) 1 $3,458,000 Total Rounded Total $14,966,000 $I5,ooo,olnJ Notes: ’ Costs include pavement, earthwork, signals, demolition, traffic control, drainage, utilities and minor items. ‘Costs include pavement, minor grading, demolition, traffic control, drainage, utilities and minor items. 3 Conceptual Design Report, dated 10 April 1992 (Alternative 3 Costs Updated) -0 ~\9853003K\l-ll-C-R.DOC\4-Dec-98\SDG 3-17 -. - SECTIONFOUR Conclusions - 4.1 CONCLUSIONS The findings of this environmental constraints and opportunities study are as follows: Of the topics studied in this report, no significant environmental constraint has been identified that would preclude the project from being constructed. Two geotechnical constraints (sea caves and liquefiable soils) have been identified that will require further study and specific treatment during the design phase of the project. Neither of these issues pose a significant problem for project development. The project area is highly disturbed and the only area with valuable biological resources is the Encinas Creek drainage. Impacts to the creek and adjacent wetlands are expected to be minimal and would not pose any unusual restrictions or permitting problems with regulatory agencies. One cultural resource site will require further evaluation to determine its significance. Standard treatment and recovery methods will likely be sufficient to mitigate any impacts to this site from the project. Two bridges located across Encinas Creek on the southbound lanes of Carlsbad Boulevard were built in 1928 and may be historically significant. Further evaluation of the historical significance of these bridges is recommended if they are deemed to be a part of the overall project. No previously recorded paleontologic sites have been identified within the project area. Monitoring for paleontologic resources during grading of geologic formations with the potential to yield fossils should be considered. Noise levels will increase from 0 to 2 decibels on the east side of the northbound lanes of Carlsbad Boulevard, and decrease by a similar amount on the west side of the southbound lanes of Carlsbad Boulevard. The City’s exterior noise standard may be exceeded at the Solamar Mobile Home Park due to the expected increases in traffic and along Carlsbad Boulevard. The realignment of the southbound lanes of Carlsbad Boulevard will contribute to, but not cause, this standard to be exceeded. Mitigation of the traffic noise to meet City standards can easily be achieved. Because of its proximity to the coast and open vistas to the east, views fi-om Carlsbad Boulevard are extremely valuable. As the project progresses, careful use of appropriate landscaping, design guidelines, and grading of bluff tops will be necessary to meet the visual quality goals and objectives of the City of Carlsbad General Plan. -0 W:\9853003K\l-llCR.DOC\4-Dec-98\Sffi 4-1 SECTIOWFIVE References - -.- r r a-- Bolt, Beranek and Newman. December 3 1, 1971. Noise From Construction Equipment and Operations, Building Equipment, and Home Appliances, prepared for the U.S. Environmental Protection Agency. Washington, D.C. Boyle Engineering Corporation. 1992. Palomar Airport Road Connection to Carlsbad Boulevard Conceptual Design Report. California Coastal Commission. 198 1. “Statewide Interpretive Guidelines - Geologic Stability of Blufftop Development”. California Department of Boating and Waterways and San Diego Association of Governments. 1994. “Shoreline Erosion Assessment and Atlas of the San Diego Region,” Volumes I and II. City of Carlsbad. 1998. Approval of Funds and the Consultant Agreement Contract with Woodward-Clyde International Americas for the Carlsbad Boulevard Realignment Study. City of Carlsbad. 1997. Review Proposed Program for the Realignment of Carlsbad Boulevard from Manzano Drive to Batiquitas Lagoon. Diehl, George M., ed. 1973. Machinery Acoustics. John Wiley & Sons, Inc. New York, New York. Eisenberg. 1986. Pleistocene and Eocene Geology of the Encinitas and Ranch0 Santa Fe Quadrangles. Gallegos & Associates. 1998. Cultural Resource Survey for the Carlsbad Boulevard Realignment Project. Moffatt & Nichol Engineers. 1998. “Revised Final Technical Report, Opportunistic Beach Fill Criteria and Concept Design”. , San Diego Association of Governments. 1993. “Shoreline Preservation Strategy for the San Diego Region”. Sherman, D.J., et. al. 1998. “The Fate of Fine Sediment in a Suspension Plume: Ponto Beach, California”. Tan, S.S. 1986. “Landslide Hazards in the Encinitas Quadrangle, San Diego County, California,” Landslide Hazard Identification Map No. 4, DMG Open-File Report 86-8. Wallace, Roberts & Todd (WRT). 1998. Visual Analysis. Carlsbad Boulevard Realignment Study. Woodward-Clyde International-Americas (WCIA). 1998a. Biological Resources Report. Carlsbad Boulevard Realignment Study. Woodward-Clyde International-Americas (WCIA). 1998b. Noise Assessment Report. Carlsbad Boulevard Realignment Study. -0 W:\9853003K\1-11-CR.CQC\4-0ec-9.8\SDG 5-l