Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
SUP 2020-0001; VISTA-CARLSBAD INTERCEPTOR 1; SEWER ACCESS ROAD IMPROVEMENTS; 2017-04-21
VISTA-CARLSBAD INTERCEPTOR {VCl) SEWER ACCESS ROAD IMPROVEMENTS PRELIMINARY DESIGN REPORT [DRAFT] April 21, 2017 Prepared for: City of Vista I"'\ ~ CITY Of VISTA Prepared by: David Evans and Associates, Inc. DAVID EVANS ANo ASSOCIATES I N C ~ CITY OF VISTA Table of Contents 1. Introduction a. Project Description b. Scope of Work c. Existing Access Road Description i. Research and Field Investigation ii. Existing Maintenance Equipment Review 2. Design Criteria a. Geometrics b. Horizontal Alignment c. Vertical Alignment d. Drainage e. Manhole Access f. Access Road and Pipe Materials 3. Preliminary Design Studies and Analysis a. Biological and Cultural Review b. Right-of-Way Review c. Hydrology d. Maintenance Equipment 4. Access Road Alternatives a. No Build b. Alternative 1 c. Alternative 2 5. Easement Acquisition a. Proposed Permanent Easements b. Temporary Construction Easements 6. Project Schedule 7. Benefits and Impacts Analysis 8. Estimate of Probable Construction Cost 9. Conclusions and Recommendations DAVID EVANS "Nr,ASSOCIATES ,-;c ~ CITY OF VISTA l I Appendix: A-As-Builts B -Utility Research C-Field Observations and Photos D -Boundary Map E -City Standard Drawings F -Alternatives ~ 1tilf DAVID EVANS A~inASSOCIATES !"IC . @, ~ CITY OF VISTA 'I DAVID EVANS 1o.,,mASSOCIATES ,,,,ic 1. Introduction a. Project Description The Vista-Carlsbad Interceptor Reach 1 (VCl) conveys wastewater from the City of Vista's (City) sewer system for treatment and disposal at Encina Water Pollution Control Facility (EWPCF) in Carlsbad. VCl conveys approximately 5.4 million gallons per day (MGD) of wastewater in a 36-inch diameter pipe and is located within environmentally sensitive areas upland of Buena Vista Creek in the City of Carlsbad. VCl was constructed in 1985 and capacity is shared with the City of Carlsbad. The City owns 96.6% of the capacity and the City of Carlsbad owns 3.4% of the capacity. A sewer maintenance road access was constructed by the City during construction which has degraded over time primarily due to erosion from nuisance and storm water flows. Direct access by way of an improved road is also not provided to a number of manholes within the study area. Therefore, the project consists of providing all weather access to the manholes for VCl that are between the end of Haymar Drive west of College Avenue and the Carlsbad Golf Center on 2711 Haymar Drive east of El Camino Real. The project is proposed to improve sewer maintenance access to provide City Wastewater crews convenient, long term accessibility to the OVl pipe line. An aerial map of the project site is provided in Figure 1. Figure 1: VCl Project Site EXISTING SE ~ CITY OF VISTA b. Scope of Work ~ 1ffilT D.l\VID EVANS ASSOCIATES·,,,,, David Evans and Associates, Inc. (DEA) prepared preliminary designs and evaluated alternatives for providing access to the VCl manholes. The scope of work includes the following: • Perform as-built research and site investigation • Perform utility research • Review of existing maintenance equipment and methods • Perform boundary and supplemental ground survey • Preparation of boundary and property line base map • Preparation of preliminary sewer access road designs • Perform alternative maintenance equipment research • Perform hydrology analysis • Evaluation of permit and environmental constraints • Evaluation of right-of-way constraints • Preparation of probable construction cost estimate • Preparation of cost benefit analysis • Perform constructability review • Facilitate Value Analysis Workshop • Preparation of Preliminary Design Report The detailed scope of work is included in the fully executed agreement between the City of Vista and DEA for professional engineering design services dated June 28, 2016. c. Existing Access Road Description i. Research and Field Investigation Existing sanitary sewer as-built plans and digital AutoCAD topography was provided by the City and utility plans were obtained from utility purveyors with facilities within the project limits to be used as base and background information for the preliminary sewer access road designs and alternative analysis. A field investigation was also performed. Record Document Review The Buena Vista Creek Outfall Sewer Phase II as-built plans provided by the City were reviewed and provided information on existing locations of the VCl manholes, the number and location of Caltrans SR-78 culverts that discharge run- off to the Buena Vista Creek as well as the location of the City of Oceanside's two existing sewer lines and the associated easement. The as-built plan sheets pertaining to the projects limits are included in Appendix A. ~ CITY OF VISTA D/.,VID EVANS t,~,:, AS SOC I AT ES In addition to City record research, DEA obtained utility plans and as-builts for utility purveyors with facilities within the project limits. Existing utilities including the VCl sewer line are listed below and a utility base map is provided in Appendix B. • City of Vista -Vista-Carlsbad Interceptor Reach 1-36-inch Vitrified Clay Pipe (VCP) • City of Oceanside -Sewer Line -15-inch VCP • City of Oceanside -Sewer Line -24-inch VCP • San Diego Gas and Electric -Overhead Electrical Lines • San Diego Pipeline Company -Pipeline Field Investigation Upon completion of the record document review, DEA performed a field investigation with City staff and a representative for the California Fish and Wildlife on August 10, 2016. The field investigation provided information on the condition of the existing access road and sewer manhole cones and covers, location, material type, and condition of existing culverts crossing the access road, and a visual assessment of adjacent properties and natural vegetation. An aerial photo with field observations and site photos is provided in Appendix C. Field Survey The City provide 2-foot aerial topography in AutoCAD format for the project area to be used as base information for the purpose of the preliminary sewer access road design. DEA supplemented the 2-foot aerial topography with a boundary survey to locate property lines and a ground survey to locate the existing VCl manholes within the project limits. The survey base file with topography, ground survey, and property line and easement information is provided in Appendix D. Findings Through record research and field investigations, the existing site conditions can be summarized by the following: 1. Existing 36-inch VCP sewer connects to manhole 22 on the west at the Hayward Drive cul-de-sac and traverses easterly running parallel to State Highway 78 and connecting to manholes 23, 24, 25, 26, and 27. At manhole 27, the sewer line traverses southeasterly along the southerly property line of APN 167-040-31-00 and includes manholes 28, 29 and 30 before reaching manhole 31 at Hayward Drive. 2. Within project limits the existing access road is earthen. 3. Between VCl sewer manholes 24 and 25, there is a natural low point in the existing access road without a culvert to convey run-off across the road. ~ CITY OF VISTA DAVID EVANS •No ASSOCIATES ,Ne 4. Between VCl sewer manholes 25 and 26, there is an existing drainage crossing without a culvert pipe to divert run-off from the surface of the access road. 5. Southeast of VCl sewer manhole 26, the cross fall of the existing access road exceed 2-percent. 6. Southeast of VCl sewer manhole 27, there is an existing drainage crossing without a culvert pipe to divert run-off from the surface of the access road. 7. Southwest ofVCl sewer manhole 29, the Buena Vist a Creek bank is eroding adjacent to the south side of the existing access road. There are gabions currently in place to prevent further erosion. 8. Southeast of VCl sewer manhole 30, there is an existing water well pump that serves APN 167-040-31-00. 9. Southeast of VCl sewer manhole 24, an existing High Density Polyethylene Pipe (HDPE) access road culvert. 10. East of VCl sewer manhole 25, an existing ductile iron pipe (DIP) access road cu Ive rt. 11. Between VCl sewer manholes 25 and 26, two existing reinforced concrete pipe (RCP) and HDPE access road culverts. 12. On existing maintenance road southeast of VCl sewer manhole 27, an existing PVC access road culvert. 13. Near VCl sewer manhole 24, an existing 24-inch Corrugated Metal Pipe (CMP) storm drain cu lvert discharges storm water and nuisance run-off south and away from SR 78. 14. Near VCl sewer manhole 25, an existing 42-inch CMP storm drain culvert discharges storm water and nuisance run-off south and away from SR 78. 15. Near VCl sewer manhole 26, an existing 48-inch CMP storm drain culvert discharges storm water and nuisance run-off south and away from SR 78. 16. Near VCl sewer manhole 27, an existing 24-inch CMP storm drain culvert discharges storm water and nuisance run-off south and away from SR 78. 17. Existing City of Oceanside 15-inch and 24-inch sewer lines that are located south of the VCl sewer line within the project limits. Both Cit y of Oceanside sewer lines are located in a record 16-foot easement. ii. Existing Maintenance Equipment Review On August 2, 2016, DEA met with City maintenance staff and performed a review of the City's existing sewer maintenance fleet to gain an understanding of the City's current maintenance means and methods. A list of the City's current maintenance equipment is provided in Table 1. The City currently owns and operates a limited fleet of low impact maintenance equipment which includes a tracked rodder (Wacker RD880) and a tow behind jetter (US Jetting 4018/300SE). This equipment provides maintenance staff with the ability to access most manholes within the VCl project limits. Although these pieces of equipment provide lower impact access, they do not provide the ability to clean and ~ CITY OF VISTA DAVID EVANS 1:1Nr ASSOCIATES ,,._c clear sewer mains the same as full size equipment such as a vactor truck. A discussion of various equipment available to aid maintenance crews working in limited access locations is provided in Section 3d. Table 1: City's Current Maintenance Equipment Veh. Vehicle Name Vear Make/Model GVW No. 217 Stormwater Vactor 2006 Sterling L7501 247 Standby Pickup Truck 2003 Ford F250 8800 501 Service and Repair 2000 Ford F350 XL Super Duty 4x4 4800 Crew Chief 502 l&E Crew Chief 2003 Ford 450 4x4 15000 503 Wayne Baller 2004 Ford FSS0 4x4 Supercab 17500 504 Compressor sos S&R Crew Truck 2005 Ford F450 4x4 15000 507 Mini Jetter 2013 US Jetting 4018/300 SE 3000 508 Flatbed/Crane 1991 Ford FT900 509 Backhoe 2002 Caterpillar 420D 19030 513 Pull-in-Machine 1991 518 Wayne Baller Trailer 1994 519 Skiploader 1998 Ford New Holland Tractor 520 Flatbed Equipment 1990 Eager Beaver Trailer 6200 Trailer 528 Crew Chief 2000 Ford F350 4x4 Super Duty 9900 530 Roller 1994 Wacker RD880 531 Roller Trailer 1995 KARAV 1140 539 Vista Standby Truck 547 Power Rodder 1997 International 4800/Champion 26500 548 Toro Truck 2000 Toro 330-D Workman 2400 555 Shoring Trailer 1998 Mighty Mover 7000 556 Air Supply Trailer 2002 Hallmark Trailer 557 Vista Vactor -Reserve 2006 International 4400 25989 565 Service Truck 1995 Ford F8000 29000 566 TV Truck -Envirosight 2013 Ford F450 4x4 Super Duty 16500 567 Crawler 577 Vista Vactor -Sub 2008 International 7400 43000 Area 1 582 Sign Trailer 2001 Ronco Trailer 2650 587 Vista Vactor -Sub 2009 International 7400 41000 Area 2 592 Confined Space Trailer 2010 Ronco Trailer 597 Buena Vactor 2013 Freightliner /Vactor 46000 782 OPS Mgr Vehicle 2008 Ford Escape 2103 Fleet Service Vehicle 2003 Ford F450 XL Super Duty 5732 Supervisor Truck 2004 Chevy 3500HD 4x4 9200 ~ CITY OF VISTA DAVID EVANS "'" ASSOCIATES ~c 2. Design Criteria a. Geometrics The proposed access road geometrics are based on the City Standard Drawings SWR-22, Sewer Access Road Turnaround Types, and SWR-23, Sewer Access Road Structural Alternatives. The geometrics are also governed by the alignment of the existing access road between the westerly project limit and VCl sewer manhole 26. City standard drawings referenced in this document are provided in Appendix E. b. Horizontal Alignment The horizontal alignment has been dictated by the following constraints and guidelines: • Use the existing access road alignment where sewer manholes are directly adjacent • When diverging from the existing access road, use recorded easement as alignment • Minimize grading by establishing alignment parallel to contours • Minimize impacts to private properties and environmental habitat • Avoid existing utilities c. Vertical Alignment The vertical alignment has been dictated by the subsections herein and considers the following: • Maximum longitudinal slope of 8-percent • Maximum access road cross fall of 2-percent • Minimize impacts to private properties and environmental habitat. • Eliminate low points due to erosion • Provide adequate clearance when crossing existing utilities • Provide adequate cover over access road culverts d. Drainage At points where existing drainage courses cross with the proposed access road, HOPE pipes will be installed to convey storm water and nuisance run-off under the access road and away from the crushed rock surface. Corrugated HOPE pipes can be placed with a minimum of 1- foot of cover which is a benefit in areas where providing adequate cover may be a challenge. HOPE is also light weight when compared to other pipe materials and can be moved and installed by hand or w ith small machinery if it needs to be replaced. e. Manhole Access ~ CITY OF VISTA ' . DAVID EVANS a►mASSOCIATES :i,.,;e A minimum 10-foot radius of crushed rock base will be provided around each manhole. This 10-foot radius is measured from the center of manhole cover to the edge of the crushed rock base. Where the manhole is located within the proposed road, the proposed concrete collar and cover (SWR-30C) will be flush with the crushed rock base surface to allow maintenance vehicles to drive over the manhole cover. When a manhole is adjacent to the sewer access road or within an area at risk of flooding due to its proximity to an existing creek, a raised concrete manhole collar (SWR-30A) will be provided. f. Access Road Materials Access road will be constructed with 3-inch crushed rock which provides a drivable yet permeable surface within an environmentally sensitive area. The section will be 6-inches thick over compacted native material. A larger 3-inch rock is proposed which is a change from the Type A section outlined in the City Standard SWR-23 which requires ¾-inch gravel over 2-inch aggregate base. The City expressed concern that the smaller ¾-inch gravel would migrate over time due to vehicle use and/or storm water run-off and therefore a larger crushed rock would be more appropriate. 3. Preliminary Design Studies and Analysis a. Biological and Cultural Review A biological, wetland, and cultural evaluation was performed by TRC Solutions Inc. to provide environmental constraints that aided in determining the preferred access road design through the alternative analysis process. Biological Resources The environmental study limits are between SR-78 to the north and the Buena Vista Creek Ecological Reserve to the south and is shown on each of the alternative exhibits in Appendix F. The northern study limits parallel the southern edge of SR-78 except at the eastern end of the project at the location of the Marron Adobe. Within the project vicinity, the Buena Vista Creek Ecological Reserve is managed by the California Department of Fish and Wildlife and is comprised mostly of Southern Riparian Scrub and Southern Arroyo Willow Riparian Forest. A general biological survey was conducted on December 2, 2016 with the vegetation type and associated area provided in Table 2 and vegetation mapping provided in Figure 2. Table 2: Existing Vegetation Environmental Study Area Vegetation Total Acres December 2, 2016 15.61 Disturbed 5.08 Baccharis salicifolia 2.45 Coastal Sage Scrub 2.30 Baccharis salicifolia -Disturbed 2.14 Southern Riparian ___________________________ 0.98 --------------------------------- ':) ~ CITY OF VISTA ' . • DAVID EVANS A.~mASSOCI.ATES •NC Coastal Sage Scrub -Disturbed 0.48 Heritage Tree 0.09 (appx) Figure 2: Vegetation Map Plant Species Table 3: Plant Species Native Species Non-Native Species Hesperoyucca Quercus agrifolia Ficus carica** Sa Isola tragus whipplei Sambucus sp. Nicotiana Limonium Adenostoma Deinandra glauca** sinuatum fasciculatum fasciculatum Marrubium Ricinus communis Artemisia californica Salvia mellifera vulgare Carpobrotus Rhus integrifolia Heteromeles Bromus sp. edulis*** Salvia apiana arbutifolia Bromus Vaccinium sp. Heterotheca Baccharis salicifolia diandrus** Pennisetum grandiflora Distichlis spicata Bromus setaceum** lsocoma menziesii Erigeron hordeaceus Malvella leprosa Ambrosia canadensis Bromus Helminthotheca a ca nth icarpa madritensis * * * echioides Cucurbita Foeniculum Vinca major** foetidissima vulgare*** Hirschfeldia incana** ~ CITY OF VISTA Previous Observations Centaurea melitensis** Oxalis sp. OAVID EVANS "-Nr ASSOCIATES •~1 ** denotes Cal/PC moderate ranking *** denotes Cal/PC moderate high ranking The CNDDB noted plant populations of Wiggins' cryptantha (Cryptantha wigg1ns11, California Rare Plant Rank (CRPR) 1B.2), thread-leaved brodieae (Brodiaea filifolia, CRPR List 18.1, Federally Threatened, State-Listed Endangered), and California adolphia (Adolphia ca/ifornica, CRPR List 2b.l) and arthropod populations of the California overwintering population of monarchs (Danaus plexippus) and federa lly-threatened vernal pool fairy shrimp (Branchinecta lynchi). None were observed during the biologica l survey. However, it is not the correct season to survey for either of t he herbaceous plants. Preliminary Recommendation Wiggins' cryptantha is an annual herb that blooms February-June and rare plant surveys would be recommended for the spring prior to work. Animal Species Table 4· Sensitive Species Sensitive Species Other California gnatcatcher White-crowned sparrow Location 1. 11S 471343 3671185 Anna's hummingbird Location 2. 11S 470634 3671291 Bushtit House wren Red-shouldered hawk Red-tailed hawk Turkey vulture House finch Coyote-scat Woodrat-midden Opposum-tracks Observed During Survey Nine avian species were observed including the coastal California gnatcatcher (Polioptila ca/ifornica californica), a USFWS federally threatened species and a CDFW Species of Special Concern. ~ CITY OF VISTA .. DAVID EVANS A"tnASSOCIATES ,,._c Woodrat middens are present within the project area with one on the southern edge of the existing dirt road slated for improvements. Previous Observations Through use of the CDFW California Natural Diversity Database {CNDDB; CDFW 2014), previous observations of the federally and state-listed endangered southwestern willow flycatcher (Empidonax trail/ii extimus), federally and state-listed endangered least Bell's vireo (Vireo be/Iii pusillus), and two CDFW Species of Special Concern, the yellow-breasted chat (lcteria virens) and yellow warbler (Dendroica petechia) were noted within close proximity. Additionally, the CDFW Fully Protected white-tailed kite (Elanus leucurus) was located in the area. Preliminary Recommendations Observations point towards the need for Focused Avian Surveys to be conducted as well as general Nesting Bird Surveys. Wood rat middens are likely to be impacted by work activities and should need relocating. Waters Two existing culverts going under the existing road were observed at 470519 3671308 and 470745 3671271. There is a small pool of standing water at the northern end of the second culvert, at the base of the slope to Highway 78. It is unclear if this water is generally present but is more likely due to the recent rains. CDFW wetlands are located immediately south of the project area within the Ecological Reserve with a slight overlap in one area. The Buena Vista Creek is also located within the Reserve and is characterized as a CDFW California Streams. Cultural Resources Records Review TRC requested an archival records search review from the South Coastal Information Center, an archival repository belonging to the California Historical Information System (CHRIS). TRC also reviewed historical aerials, topographic maps and additional literature related to the history of the region. Table 5 below provides resource listings within 1 mile of the Environmental Study Area. Table S· Resource Listing Resource ID Type National Register Status CA-SDl-000630 Prehistoric Not Eligible CA-SDl-000631 Prehistoric Not Eligible CA-SDl-000632 Prehistoric Not Eligible ~ CITY OF VISTA DAVID EVANS , ... .,ASSOCIATES SC CA-SDl-000633 Prehistoric Not Eligible CA-SDl-000634 Prehistoric Not Eligible CA-SDl-000636 Prehistoric Not Eligible CA-SDl-004979 Prehistoric Not Eligible CA-SDl-004981 Prehistoric Not Eligible CA-SDl-004990 Prehistoric Not Eligible CA-SDl-005077 Prehistoric Eligible CA-SDl-005213 Prehistoric Not Eligible CA-SDl-005437 Prehistoric Not Eligible CA-SDl-005601 Prehistoric Not Eligible CA-SDl-005651 Prehistoric Eligible Component CA-SDl-005652 Multicomponent Eligible CA-SDl-006138 Prehistoric Not Eligible CA-SDl-006139 Prehistoric Eligible Component CA-SDl-006955 Prehistoric Not Eligible CA-SDl-007242 Prehistoric Not Eligible CA-SDl-007880 Prehistoric Not Eligible CA-SDl-008913 Prehistoric Eligible Component CA-SDl-008914 Prehistoric Not Eligible CA-SDl-009472 Prehistoric Not Eligible CA-SDl-009473 Prehistoric Not Eligible CA-SDl-009474 Historic Not Eligible CA-SDl-009917 Prehistoric Not Eligible CA-SDl-009967 Multicomponent Not Eligible CA-SDl-010235 Prehistoric Not Eligible CA-SDl-010236 Prehistoric Not Eligible CA-SDl-0107 46 Prehistoric Not Eligible CA-SDl-0124 71 Prehistoric Not Eligible CA-SDl-015016 Prehistoric Not Eligible CA-SDl-015732 Prehistoric Not Eligible P-37-025143 Historic Not Eligible CA-SDl-017864 Prehistoric Not Eligible CA-SDl-018819 Prehistoric Not Eligible CA-SDl-020776 Prehistoric Not Eligible CA-SDl-020777 Prehistoric Not Eligible Site Reconnaissance TRC conducted a pedestrian survey of the project area on December 2, 2016. The survey was conducted by a Registered Professional Archaeologist with extensive knowledge of regional resources. The archaeologist conducted a directed pedestrian survey of the area. All cultural resources identified through the Records Review located either within the project area or immediately outside of the project area were revisited and evaluated to determine if site update records should be prepared. All new resources, including isolated ~ CITY OF VISTA DAVID EVANS ANnASSOCIATES 1-..c resources and sites identified were recorded for using Department of Parks and Recre.ation 523 forms for cultural resources. Qualifications Jessica J. Auck is a Registered Professional Archaeologist with approximately ten years of professional experience throughout California and the west who meets the Secretary of the Interior's standards for Historical Archaeology, Architectural History and History. Her professional experience includes monitoring numerous construction projects, participation in multiple pedestrian surveys, authorship of regulatory reviews and site, building and landscape evaluations as well as data recovery (excavations) and collections management and evaluation. She has also liaised with multiple Native American tribes and representatives as well as with multiple agencies including the Bureau of Land Management, California Energy Commission and the California State Historic Preservation Office. Site Information The Environmental Study Area is located immediately south of a federally recognized history property and contains a locally recognized historic resource tree. Cultural resources are provided in Table 6 and sensitivity mapping is provided in Figure 3. Table 6: Cultural Resources Environmental Study Area Cultural Resources Acres December 2, 2016 Highly Disturbed, Reduced Sensitivity 7.77 Mid-high Sensitivity 1.32 Unknown Sensitivity 1.08 Area includes Heritage Tree Highly Disturbed, Reduced Sensitivity No further field survey or study is required for this specific area; ok to proceed without further study or contingency plan. Mid-high Sensitivity Potential resources were discovered and further studies will be needed. An archeological contingency plan for late discovery during construction activities is applicable, regardless of whether further cultural studies determine whether resources are present. Unknown Sensitivity In areas of unknown sensitivity, it is customary to keep ground cover and vegetation undisturbed for the purposes of archeological surveys. Further surveys cannot be performed prior to construction. In areas with dense vegetation, an archeological contingency plan for late discovery during construction activities is applicable. Monitoring will be required since a survey was not possible. ~ CITY OF VISTA b. Right-of-Way Review DAVID EVANS MmASsoc1A·rEs ◄1',;c Recorded easements within the project limits were researched and mapped by DEA and Clark Land Resource, Inc., from recorded parcel maps and title reports. The research confirmed a number of easement owners which include the City of Vista, City of Oceanside, San Diego Gas and Electric Company, and Shelly Hayes Caron. A boundary map showing property lines, easements, and owners is provided in Appendix D. Through review of available documents, it was confirmed that the 20-foot wide VCl sewer pipeline easement shown on the Buena Vista Creek Outfall Sewer Phase II as-built plans was not recorded for the entirety of the project length through parcel 167-040-38-00. The easement was only recorded for a portion of the pipeline that is located parallel to the southerly property line of parcel 167-040-31-00. There is also a 600 square foot radius fillet portion of the proposed easement that was identified but never recorded which is shown on Detail 'A' of the boundary map provided in Appendix D. c. Hydrology ~ CITY OF VISTA . . ' DAVID EVANS """ASSOCIATES .. e Based on the San Diego Regional Water Quality Control Board (SDRWQCB) Basin Plan, the project site is located within the Carlsbad Hydrologic Unit, specifically within the Buena Vista Creek Hydrologic Area (904.20). The project falls within the municipal limits of the Cities of Oceanside and Vista. The site topographic features consist of relatively meandering terrain with grade elevations ranging from 35' Mean Sea Level (msl) in the east towards 115' msl in the west. It is noted that the site has utilized import to backfill portions of the alignment as part of the original construction. The VCl alignment has several drainage crossings that either drain the SR-78 alignment and/or provide continued conveyance under the maintenance road. There are at least 5 drainage culverts ranging from 24" to 48" in diameter (corrugated metal and reinforced concrete pipes) in addition to several overland earthen ditches that convey localized runoff. Most of the drainage features generally drain towards the south and east with drainage patterns generally draining from west to east towards the ocean. In the current configuration, existing culverts located north of VCl collect runoff from SR-78 and/or collect localized runoff that discharges onto the existing maintenance access road. The existing overland earthen ditches also convey localized runoff towards and/or beyond the maintenance access road. It is noted that discharge volumes have not been computed for this review. Review of the National Flood Insurance Program (NFIP), Flood Insurance Rate Map (FIRM), Map Numbers 06073C0762G and 06073C0766G (Effective Date May 16, 2012), for San Diego County and Incorporated Areas reveals that the project is located within in Base Floodplain Zone AE and other Flood Areas (Zone X). As defined by FEMA, Zone AE is an area where base flood elevations have been determined. Zone AE is also a Special Flood Hazard Area (SFHA) that will be inundated by the flood event having a 1-percent chance of being equaled or exceeded in any given year. The 1-percent annual chance flood is also referred to as the base flood or 100-year flood. Zone X is a moderate flood hazard area between the limits of the base flood and the 0.2-percent-annual-chance (or 500-year) flood. Refer to Attachment A for the FIRM Maps 06073C0762G and 06073C0766G (Effective Date May 16, 2012). A summary of peak discharges is provided below for Buena Vista Creek (Ref. FEMA Flood Insurance Study (FIS) Report 06073CV001D, [Volume 1 of 11]). Table 7: Hydrology Data BUENA VISTA CREEK (Peak Discharges in Cubic Feet per Second) Flooding Source 10%Annual-2%Annual-1%Annual-0.2% Annual- and Location Drainage Chance Chance Chance Chance Area (10-Year (SO-Year (100-Year (500-Year (sq. miles) Flood) Flood) Flood) Flood) Upstream of Interstate 20.8 2,000 5,600 8,500 19,000 Highway 5 At Sunset Drive 15.9 1,700 5,100 8,000 18,000 Just Downstream of 9.5 3,300 5,480 6,540 12,000 Melrose Drive At State Route 78 9.3 3,170 5,320 6,340 11,000 d. Maintenance Equipment ~ CITY OF VISTA • DAVID EVANS "-NPASSOCIATES t.;C As part of the alternative analysis, research of possible alternative equipment was performed to determine if there is equipment that could eliminate the need for improving access or could limit the footprint of any proposed improvements. Various equipment is available to aid maintenance crews when working in limited access locations. Generally, equipment produced for the purpose of working within easements or sensitive areas is lighter and uses drive systems that distribute the weight, causing less impact to vegetation and the natural ground. The list below identifies the equipment available to reduce ground and vegetation impacts. Alternative Equipment & Limitations Rubber Tracked Skid Steer -ASV Positrack VT-70 -This bucketed skid steer can be used by crews for gaining access to manholes, and would be used to bring bulk materials such as crushed rock to a work site. The tracks provide a ground pressure less than 5 psi that would reduce damage to vegetation and may provide better access in softer soils. Tow-in Rodder/Jetter -Rodders and Jetters are available in a wide variety of sizes from handheld to truck mounted. The handheld units are largely ineffective in sewer mains, and truck mounted rodders and jetters require developed and stable access roads for access. Tow in or rubber tracked jetters and rodders, generally referred to as "Easement Machines", provide an intermediate range of effectiveness at sewer cleaning. Easement machines have less power and a shorter range within a sewer main and may not be able to clear the more stubborn debris or large rocks. Off-road Utility Vehicle -UTV's are available that can travel on variable terrain without the need for access roads. UTV's are used for transporting crews and small tools to a work site. These vehicles do have a limitation in that they cannot travel on very steep terrain or in soft soil areas. UTV's are low impact in that they can travel over grassy areas but again are limited, because they cannot travel through heavily treed areas or thick brush. Portable Bridges -Portable bridges are available that can be placed across drainages or creeks to aid in emergency access to sewer mains or manholes. These bridges can be purchased or rented up to 50 feet long. They generally require a developed access up to the placement point and are a good way of avoiding impacts to regulated waters. Depending on the bridge length, crane pads may need to be developed to place temporary bridges. Stability Plates -Stability plates can be purchased in either steel or fiberglass and are placed along a travelled alignment to provide stability to heavy vehicles travelling over soft soils. Plates can greatly reduce impacts created by most vehicles and equipment. Bucket truck* -A bucketing operation typically includes a truck mounted apparatus that used a cable to drag a bucket through a main for purposes of cleaning. Debris removed is placed in a second vehicle and hauled to an appropriate disposal site. There are no alternate options that provide a lower impact to a bucketing operation. Bucketing is a very effective method for removing a large quantity of sediment and debris but full access is necessary. ~ CITY OF VISTA DAVID EVANS ••oASSOCIATES ,,c *Bucketing and Vactoring are the most effective methods for cleaning sewer mains. Risk & Mitigations When evaluating access requirements for manholes, the risk assessment table below identifies risk and mitigations to be considered. An evaluation should include access limitations, access time and environmental impacts created. Table 8: Access Assessment Risk Issue/Concern Impact Mitigation Access Limitations -Access limitations may create Best -Provide vegetation, soft soil, steep a spill due to the inability to equipment access to all slopes or other geographic maintain the sewer. Access manholes. Equipment features limit the ability to limitations may also create a needs to include a gain access to a manhole delay in the ability to rectify a Vactor, a CCTV truck, and required for maintenance or sewer issue in a timely a Bucket Truck. Conduct during an emergency event. manner. periodic routine maintenance of access to ensure access is passable and unrestricted. Minimum -Provide and maintain a smaller access road. In the case of a straight through manhole, large equipment access may not be a requirement. Limitations -Heavy Vegetation must be cut and removed; a solid ground surface is necessary for nearly any type of equipment access. Access Time -restricted In the event of a spill, a Best -Provide access and using low impact timely response in necessary. equipment access to access equipment may delay If easement/low impact manholes within access to areas farther inside equipment is relied upon for easements that allow of easement areas. Tracking access deep within an vactors and bucket trucks equipment through a long easement, there will be quick access. stretch of an easement will delays to the response. create a delayed response in Minimum-Provide an emergency situation. access roads along the ~ CITY OF VISTA . . Environmental Impacts -If Non-permitted impacts to environmental impacts are sensitive habitat or wildlife not identified and permitted will create additional well in advance of mitigation measures required maintenance or emergency by the City. Sometimes nine access needs, the to one mitigation is required department may need to for impacted areas. If access resolve environmental issues is not provided, crews may after the fact. develop access without the benefit of environmental monitoring staff. DAVID EVANS •soASSOCIATES ~" alignment of the sewer to provide access near the manholes, using low impact equipment for a short distance from the access road to the manhole if the access road cannot be immediately adjacent to the manhole. Best -Obtain all permits for development of full access; follow the requirements and complete routine access road maintenance during the appropriate seasons. Minimum -Map sensitive habitat, educate field crews on areas with sensitive habitat and nesting season limitations, and make biologists available to accompany crews during maintenance and emergency efforts. ~ CITY OF VISTA 4. Access Road Alternatives DAVID EVANS ANPASSOCIATES NC This project study report considers a No-Build option and two build alternatives. The No-Build option does not require cost for immediate construction but does incur long term maintenance cost for the existing earthen access road as well as replacement cost for the pipeline if regular maintenance is unable to be performed due to access restrictions. The two build Alternatives 1 and 2 propose improving the existing access road and providing clear and direct access to each of the manholes within the project limits. The preliminary designs considered existing field conditions, equipment access, construction and easement acquisition cost, constructability, and private property and environmental habitat impacts. Exhibits for the No Build option and both build Alternatives are included in the body ofthis project report as well as Appendix F. a. No-Build The No-Build (Exhibit 1) option leaves the project site in the existing condition. The City Public Works staff will need to perform regular maintenance of the existing earthen access road as erosion of the road due to storm water and nuisance run-off will continue to occur. The City will also continue to have limited access to manholes located away from the access road which include manholes 27 through 30. These manholes do not currently have a defined direct access and are separated from the existing road by vertical elevation and natural vegetation. r ~ CITY OF VISTA Exhibit 1: No Build Option {1 of 2) LEGE!-JD PROP£JCT't' UNE DlSTINO~A -•fhJIJI. IE.ICIS11NOSfMMOIWN !AS8Al'iNTLIHf: f~lrlTALGl\.O't'UWTtl fXISTINGfllO,,O vasTINOUAMHOlt DAVID EVANS I.INOASSOCIATES "I ... VC1 SEWER ACCESS EXHIBIT NO BUILD Ul'l()""-ktlflUI ~Colit:ioNP'lr... Pl'.-. IOt ... ,thO ~ CITY OF VISTA A l Exhibit 1: No Build Option (2 of 2) £XISTINGSCWOI: _,..~ li:Xl$T'INOSTOAMORAIN LA.9£M[HT UH£ E~NlAL !Jl UCV lMl I ''""'""_., .,.,.,,,. ............ DAVID EVANS •"rASSOCIATES ~, VC1 SEWER ACCESS EXHIBIT NO BUILD ...... .v ••• I -•••OOIAT•e- 4:,0C~IIN1SO °""''°~.,,... Pl'«,tl(ll4'1"7!i0 ~ CITY OF VISTA I • • DAVID EVANS •N1>ASSOCIATES ~c b. Alternative 1 Alternative 1 (Exhibit 2) proposes to provide access to each of the manholes within the project limits by rehabilitating and improving the existing access road between Neymar Drive at the westerly project limits to a location south of manhole 28 as well as constructing two new access roads that provide direct access to manholes 27 through 31. A spur road with a City standard sewer maintenance turnaround is proposed to access manhole 27 while a new continuous access road that follows much of the recorded VC1 sewer easement along the southerly property line of parcel 167-040-31-00 is proposed to provide access to manholes 28 through 31. The existing earthen access road between manhole 28 and Haymar Drive at the easterly project limit will remain in place as it is used by the City of Oceanside, California Fish and Wildlife, and San Diego Gas and Electric Company. Considerations used for the design are as follows: • Use the existing access road alignment between Haymar Drive at the westerly project limits to just south of manhole 28 minimize grading and impacts to undisturbed and environmentally sensitive areas. • Provide a direct improved spur road to manhole 27 which allows for all weather access. • Provide a direct improved access road connection from the existing road alignment to manhole 28 and continue the proposed access road along the alignment of the recorded VC1 sewer easement to provide all weather access to manholes 29 through 31. Using the recorded easement for the proposed access road alignment reduces the cost for acquiring new easements. • Following the recorded easement also minimized the grading limits as the alignment parallels much of the natural topography in that particular area. This reduces impacts to parcel 167-040-31-00 and undisturbed areas in parcel 167- 040-38-00. • The proposed access road within the recorded easement was not proposed to continue west from manhole 28 to manhole 27 because it would cross a significant drainage course and would require more impact to undisturbed areas than providing an independent spur to manhole 27. • Raise the manhole cone and cover for manhole 31 so that it is accessible from the proposed access road. Observations as a result of the design are as follows: • Maintenance vehicles have a continual path with minimal turning movement for all manholes except manhole 27. • Temporary construction easements (TCE) will be required beyond the improved access road and/or grading limits to facilitate construction. • Existing heavy vegetation will need to be cleared to provide the improved 10-foot clear space at manholes 24 through 26. • A portion of the grading for the proposed turnaround at manhole 27 will fall within a natural drainage course and will require revegetation for erosion control purposes. ~ CITY OF VISTA DAVID EVANS IINOASSOCIATES "NC • Re-vegetation and replacement of portions of an existing irrigation system will be required due to grading impacts on parcel 167-040-31-00. • The design does not require the relocation of any existing utilities. ~ CITY OF VISTA Exhibit 2: Alternative 1 {1 of 2} 0 =i!~c:"~~~~~"'~~N.L ® INSTMt.~ECOLJMPER(:tfY(»:VIIT"S'TO l'JWO SWM-lOA. G) IH$TAUOONCl'e'TECOt..LMPfJ'tQT1'0f'VIS1'ASl0.DWO SWft-,30C, LEGEND l PA0"0SCD :r CRU!lttC) AOCt< PROPiRTY u,i, • .':J• :=::::C'WN ,t:1 ~~ l!ASf.Ml!NTl>lf ",i'~ ENl.'IAONMEHTAl STUOl'UM!t'1 EXISTING"""° CUTn'UU. & OAVUCHT UNf EXJSTWG M.V4HOU ,....,..: ~" $E'll!J;t l',¢1.,~\:'),i,.o ill om11. rYPICAI.IMM-tOliACCUS ......... w • DAVID EVANS •No ASSOCIATES VC1 SEWER ACCESS EXHIBIT ALTERNATIVE 1 ........ ANO I -Aa90CIAT•••- t)QQ"-S,,,,.tl',:I O--W,~t'17 ... p,_..1ou11tni0 ~ CITY OF VISTA . ' ' Exhibit 2: Alternative 1 (2 af 2) PROPCRTV llt<iC (XdTINQ UWEk PJCISTINO STORM tiAA1H VOST!NGl'tON> --f -• CUf1'\A.ll.D,\Y\JGHTUNe: £.lUITNG MANHOLI CONSTRUCTION NOTES 0 ~~~~~~=:fr::~:;N.L <D .,.,.,AU CONCftlTf; COUNI P!.~ (:11'1' Of \IISlA In>, 0W0. $W,--3M 0 folSTN.L~COt.1..AAPflllCITYOl'._..&TAITO OWG IV.ft..JOC. DAVID EVANS .t.NnASSOCIATES 1Nc VC1 SEWER ACCESS EXHIBIT ALTERNATIVE 1 ........... I -•••OCIAT■a- •,000--..,.,-11,0, °"-~·,,.,, ,,.......,.,.,.,,ilO ~ CITY OF VISTA DAVID EVANS ,.NoASSOCIATES NC c. Alternative 2 Alternative 2 (Exhibit 3) proposes to provide access to each of the manholes within the project limits by rehabilitating and improving the entire length of the existing access road. Individual spur roads with City standard sewer maintenance turnarounds are proposed from the existing access road alignment to manholes 27 through 30. Considerations used for the design are as follows: • Use the existing access road alignment for the entire project length to minimize grading and impacts to undisturbed and environmentally sensitive areas. • Provide direct improved spur roads to manholes 27 through 30 which allows for all weather access. • Raise the manhole cone and cover for manhole 31 so that it is accessible from the proposed access road. Observations as a result of the design are as follows: • Spurs roads for manholes 27 through 30 will require multiple turning movements for maintenance vehicles at each location. • Temporary construction easements (TCE) will be required beyond the improved access road and/or grading limits to facilitate construction. • Existing heavy vegetation will need to be cleared to provide the improved 10-foot clear space at manholes 24 through 26. • A portion of the grading for the proposed turnaround at manhole 27 will fall within a natural drainage course and will require revegetation for erosion control purposes. • Re-vegetation and replacement of portions of an existing irrigation system will be required due to grading impacts on parcel 167-040-31-00. • There will be physical permanent improvements on parcel 167-040-31-00 to provide turnarounds for manholes 29 and 30. • The design does not require the relocation of any existing utilities. ~ CITY OF VISTA Exhibit 3: Alternative 2 {1 of 2) 0 ==~~=~~ce::'::t:!.~ © ffl'TM.l C0HCRE1? C0U..AR P£R CITY OF-VISTA SlD DWO, $WR-~ @ INSTAU. CONCPETt CCUM PCR CITY Of VISTA S1D DWO. SYnt-30C, LEGEND 77 P'A0fl08IE03"'CRV$Hf0ROCI( . '. ~jl ;~~ 10~ 11'>-~, y,_\,. e• Tl-< .l~ \f.!J VUST'ftGST'OflM~ EA&fl,llNTLN CNVIROHMENTM. STUO'l'LlrMTS 'KIIS'1t U "1<~" EXIS™GROM> CVTAIIJ. & OAYIJOHT LltfC D:lt:Tlt,IQ~ D?!G:S,SCCT!QH 8[Wt:RM:Cf.lil6~ v-•cl A('(l'<:' HOAn ~1 ~ TYNCAL~HOll!N::CUS 1'1MVO,W DAVID EVANS ~NoASSOCIATES •NC VC1 SEWER ACCESS EXHIBIT ALTERNATIVE 2 &,OO~t\NI!,) 0,ltwet.lltll,,i11t1 .... ,-.... .... ,,?w ~ CITY OF VISTA Exhibit 3: Alternative 2 (2 of 2) -1..IL...1 5.)(mlNGK'V\l'iR -• ~ liXtlTlN() $T()AM ORA1N ~NIH..S'ILO'l'UM118 -~ -J. CUTll'UU & OA'I\JGHf 1.N! """""'"""""" CONSTRUCTION NOTES 0 l'lfCONS'TiltUCT V<ISTM) SEW'ER friW,IHOL.f CONI! NI) RISffl ANO IHSTAl.l UGtff'f.lt]GH'T ~~R PCA CnY OP vwtA 5Tt>. ONG. SWR.J,J, ®, INSlAU.CONCJtE.rF.OOUNt~Cl'YYOI-V!SlAITO OWO 8~ <D INl'T"ll. OONClll:«TI!: C0lJ.AA PEit CITY 01" \/!STA STD Di'IG l!l'M't·:SOC. • DAVID EVANS •NnASSOCIATES VC1 SEWER ACCESS EXHIBIT ALTERNATIVE 2 •,OO~.._..IIG O,..,,.Ca,i!eoNl!tl~ ""4N .,,,. ... ,.,110 @ ~ CITY OF VISTA l I • " ~ 5. Easement Acquisition a. Proposed Permanent Easements • DAVID EVANS .vmASSOCIATES -.,c Since both build alternatives propose improved access roads, linear easements following the alignment of the roads are proposed in the report and reflected in the tables below as well as the cost estimates. If the City prefers blanket easements, a cost comparison analysis can be provided. It has been established that the typical easement requirements for sewer lines less than 15- feet deep are 15-foot wide easements and 20-foot wide easements for lines deeper than 15- feet. Since the current width of the recorded VCl sewer easement is 20 feet wide, that width will be maintained for the portion requiring a recorded easement from the westerly property line of Parcel 167-040-31-00 to the westerly project limits at Neymar Drive. Easements for access roads will be 15-feet wide per the City Standard Drawing SWR-23. Parcels with proposed permanent easements and associated square footage areas by alternative are shown in figures below. Table 9: Alternative 1 -Proposed Permanent Easements APN Easement Purpose Property Owner Easement Area (SF) 167-040-31-00 -Shelly Hayes Caron - 167-040-38-00 Access Road California Fish and Wildlife 48,559 167-040-38-00 Sewer Line California Fish and Wildlife 35,100 167-040-39-00 Access Road California Fish and Wildlife 3,435 Table 10· Alternative 2 -Proposed Permanent Easements APN Easement Purpose Property Owner Easement Area (SF) 167-040-31-00 Access Road Shelly Hayes Caron 1,251 167-040-38-00 Access Road California Fish and Wildlife 75,416 167-040-38-00 Sewer Line California Fish and Wildlife 35,100 167-040-39-00 Access Road California Fish and Wildlife 3,555 b. Proposed Temporary Construction Easements Temporary construction easements will be required beyond the limits of the access road, drainage, and/or grading improvements to provide the space for construction activities. Areas estimated for TCE's were established 5-feet beyond the proposed improvement/grading limits. Parcels with proposed TCE's and associated square footage areas are shown in the figures below. ~ CITY OF VISTA -': I' • DAVID EVANS ANr ASSOCIATES ~c Table 11: Alternative 1 -Temporary Construction Easements APN Easement Purpose Property Owner Easement Area (SF) 167-040-31-00 Construction Shelly Hayes Caron 11,904 167-040-38-00 Construction California Fish and Wildlife 39,121 167-040-39-00 Construction California Fish and Wildlife 1,888 Table 12· Alternative 2 -Temporary Construction Easements APN Easement Purpose Property Owner Easement Area (SF) 167-040-31-00 Construction Shelly Hayes Caron 9,010 167-040-38-00 Construction California Fish and Wildlife 59,074 167-040-39-00 Construction California Fish and Wildlife 5,587 ~ CITY OF VISTA 6. Project Schedule • DAVID EVANS ANt,ASSOCIATES lf\lC The project schedule has been updated to reflect progress up to this Preliminary Design Report. Upon approval of the report, DEA will proceed with the environmental document and final design phase of the project. The final design will include 60percent, 90-percent, and 100-percent submittals. It's anticipated the environmental document will precede the final design. There is an opportunity to proceed with the final design and environmental document concurrently if desired by the City. This will accelerate the schedule shown in the figure below. Figure 4 -Preliminary Project Schedule Sewer Maint~ Accfls Road for YC1 Pl~irl• CilyofVltta PROJECT SCHEDULE 1:.,__rask Name ""'otlon I Si.rt ..... 1 .,,. I · ----n... l t.i... ~I~! I c-I •-I I •·· I --I •·-l---4. Nollce To ProcMd 1d>y? Mon 713117 rhPr~ Management 232 days Wed:7/5111 ·---232 days Wed 715117 4 1Sit• lnYHtigat.lon, Oata Cotlectk>n, and Record RH Hrch 45 days Tue 7/4117 J_ Site lr'Nelti;ation '"'"' Tue 714/11 • 6 Maps. Plans, Right-0,-Way Research 10deys Tue 7/4117 7 Utility lettors and Re10ard1 20d>l"' Tuo 7/4/11 • Sun,eying&Ma.,,,;ng 35 cbys Tu.7/"'11 ~i -• Aerial Topography & Right-of.Wey Mapping 20d>)" ,_,.'l r,. 7 0 Design Su,v,ey 10days Tue 81811 11 Geolechnk:al lnve11tigetion 45 days Tue 71411 12 . .,,,. ..... 15de)'I Tue 7/4/17 i --13 ltwffdgatlon and Geotectncal Report 30 .. ,,. Tue 7/25/1 ,. CEQA Docurnentadon and Pennttting 252 -7 Tue7/1111 15 Projec;IOel-7d>y,, Tuo711$11 ■ 16 Tochnlcal Studieo 2Sd>l"' Thu 7127111 -22 Draft lniti.at Study/Mitigated Negative Declaration (ISIMNO) 107 days? Thu !/31/11 -#-Prepare ~ of tnlent and Ottttl>ute Notice of AvialbHity 7da). .. Mon 1129/1' ..... 33 Draft 1$.IMNO P\Jblic RIMIJW 30 day,, Wed2n/18 3' Final ISIMNO 73 dayt,? WH 3121/11 ~ M-'b,10M0,ondRepo,t1ngP-1 d>y? Mon71111 t.. 45 Projec:1 App,oval Pldc Heiring 1 d•V Tue7f3111 :., ·45 . Procwe ond Flkl Nobee of Octonnk\etlOn 1 • .., Wod 11.UH 47 FIM IO.algn 221 d•ya Tue 1(5111 48 80% Plans, Specitlcatlons, and Earimatn (PS&E) 77daVI Tue 9i6/1 -· S4 Righi-of-Way Englnffflng and...,,.._ 113 dlya WN 11/2211< -~ Permitlflg 150d•ya Wed 12/20l17 ~ 90% Pianl. Spedlcationa. and Estimates (PS&E} 62 dayt Thu 12/21 /17 .. FW\llf(PS&E) 49 dava Mon 311911.!I Tu k Extemal T atkl OuntlJon.«,ly == Mileslone • Pfoi.cl Summar; Manual Summ111y Rolup Summa,y Group By Summary Manual Summary Roled Up Talk lnac:b'Ve Task ---Start--[ Rolled Up Milestone ◊ lnac:tive Milfttono ., Flnlsl><>r,ly l Rolled Up Progres■ lnaciive SUmma,y '.) =v Progm1 st"• 11111"'"''"'"""''" Marn.la!THk -0 P ... 1 7. Benefits and Impacts Analysis When developing solutions for a project there are benefits and cost associated with each proposed design that need to be evaluated in order to reach a decision of a preferred alternative. There is also the consideration to not move forward with a project or as labeled in this report the "No Build" option. Although the No Build option may not incur short term management, design, and construction cost , there are typically long term cost and impacts that can result in increased maintenance, accelerated infrastructure replacement, reduction in public safety, environmental damage, and strained public relations. A number of these impacts for the No Build option are difficult to quantify in terms of dollars allowing for a true cost comparison with build alternatives. There for a summary of elements with associated short term and long term benefits is provided in the tables below to provide a comparison between the No-build and build alternatives as well as a comparison between the two build alternatives. ~ CITY OF VISTA l , 0 II Table 12 -No Build vs Build Alternatives Element Short Term Requires additional easements for construction and access Avoids temporary construction impacts to private property Avoids temporary construction impacts to cultural and biological resources Long Term Provides unobstructed legal access to each manhole for preventative maintenance Provides all weather access to each manhole for preventative maintenance Provides unobstructed access for full size maintenance equipment Provides unobstructed access for low impact/easement equipment to each manhole Provides ready and legal access to all reaches of the sewer for emergency response to· spills and overflows Table 13 -Alternative 1 vs. Alternative 2 Element Short Term Results in increased easement acquisition cost when compared to alternative Results in increased temporary construction impacts to private property when compared to alternative Results in increased temporary construction impacts to cultural and biological resources when compared to alternative Long Term Provides continual maintenance access with minimal equipment movement when compared to alternative Maximizes the use of the existing easement when compared to alternative 8. Estimate of Probable Construction Cost No Build No Yes Yes No No No No No Alternative 1 Yes Yes Yes Yes Yes DAVID EVANS •NnASSOCIATES ~ Build Alternatives Yes No No Yes Yes Yes Yes Yes Alternative 2 No No No No No Construction cost should be considered in the selections of the final preferred layout. Since these costs are based on preliminary design, some items required for completion of the project may not have been considered. To cover these unforeseen costs, a 25% contingency has been added. The unit prices used for this estimate are based on research of similar projects. It should be understood that the Engineer has no control over many factors that can affect cost such as the @ ~ CITY OF VISTA D.L\VID EVANS ASSOCIATES following: price of labor, equipment, or the contractor's method of pricing. Furthermore, the construction costs are formulated on the basis of the Engineer's qualifications, resources, and experience. As discussed in Section 8, the no-build option can be difficult to quantify in terms of dollars for a true cost comparison with build alternatives and therefore a summary of elements with associated short term and long term benefits and impacts is provided in the Table 12 in order to compare and evaluate the No-build and build alternatives. Based on the understanding of the evaluation that the No Build option does not achieve the City's goal of minimizing the risk and results of a sanitary sewer overflow, this Section presents a cost comparison between the two build alternatives. Individual opinions of construction cost for both build alternatives are provided in the tables below. Table 14 -Alternative 1 -Preliminary Probable Cost City of Vista Date Printed: VC1 Access Road Project No.: VISTOOOO-OJ01 Prepared By: GNR Preliminary Engineer's Opinion of Probable Construction Cost -Alternative 1 ITEMS QTY UNIT UNIT COST SUBTOTAL TOTAL MOBIL12'A,TIDN ... 1 LS 12,uuu.OO $ 12.000.00 __,,,w,.1 .... !':11nnlv 1 LS O,uuu.UU O,uuu.UU f'.nnRh\Jcliof'I !':,.,.,,.\IIIVI 1 LS 15,uuu.oo 1!>,uuu.oo Soils and Materials Testina 1 LS lU,OUU,UU 10,ouu.OO o...-~-~..,. !':WPPP 1 LS lU,UUU.00 1u,uuu.uu ' ....... , .... , $ :IZ.:,uu,UU .. r.LD.an.,,, ..,.,, Grubhinc 1u1, .... ., :SI" $ U.00 $ oo,,,n.uu ~-EidAlinc sionn ,_;,.. ..,,,,.. 100 1..F $ 60.UU $ o,000.00 $ 50,IL'l.lJO ,A •A .. IF'ifl\ 1,11nn l.,T $ 30.00 $ 31,,..,.. .DO i::Ynnrt 75 l.,T $ 40.00 $ 3.uuu.00 Fine Gradina Anti ~a 68,.U4 SF $ 0.50 $ 34.162.00 Sub-Total $ w. 14.LIJU IMPR0 .,..MENTS Wlara 3• r.nia.hArl Wnr., f"4 Htifl SfoJ 1,u, .. .... Ill) • } tl!S,ILII.I.UU ln"''"fl 24• HDPE Pine n,u Lt-n,. } :ll ,UIJl).UU ~~ ~"" R""""-Install "...._._ U=hnl,,. r-~""' !I c,. 3.::ruu. } 31,.0UU.UU Driu..taC........-, IS,:xw .,,.. l. } IS,::JO'>.UU .. '""h-TntAI $ 147,104.00 RIGHT.ni=.WAV i:: ............. t 87,UY4 ~"' I$ 1.001$ 87,1"'4.00 T"""""""'' ~nnc.tn.rtion i:;,..,..,....,nt :>:.!.lfl3 :SI" I$ O.oo 1$ :.!0,4:>0.50 $ 113, ....... :iu """'I"'"" Mltin<1tinn 1 ,., ... I .. 0!!4,UW.00 $ AMll,!"'lnll,00 Sub-Total II -,:MIU,00 T-•• II wca,.11 t .:HJ -.. .,-,.1, ........ ..-.311 "'"'"" T-••• Ii 11·1a·,,~,-,.N e,,. ~ CITY OF VISTA ~ Tor D.L\VID EVANS ASSOCIATES .... ~ CITY OF VISTA Table 15 -Alternative 2 -Preliminary Probable Cost City of Vista VC1 Access Road D/.,VID EVANS i,~,r:, ASSOClATES Date Printed: Project No.: VIST0000-0001 Prepared By: GNR Preliminary Engineer's Opinion of Probable Construction Cost -Alternative 2 ITEMS I QTY UNIT UNIT COST SUBTOTAL TOTAL -r,,-ua--itl'A.~ 1 IS ~ 1? IIlll,00 12,IAIIJ.00 Develoo WsdAr ~, ,nnl" 1 LS b,uuu.00 b,uuu.W ,---~---•~-e. ,~ 1 us 10,uuu.w 15,LIUl',UIJ Soils and Materials Testin<1 1 LS 10,:,uu.uo 10,e>tll',()() ................ ,...,,, -,u,n,..,p 1 LS 10,1uu,()() 10, IAIIJ, 00 -1$ :.Z.l!IUU.IIU .. l"":laarinn onrt r..n 1hhinn 110,nn, .:,r-I$ 0.00 $ 55,.>.>.,,:,0 s:,_....,.,..MIL ~vletinn 11;.!tfl'lftYI ~ 1.11""'a ,. .. LF $ 60.00 $ 6,IAIIJ.00 $ a,, ....... :,o ..... -/C:IU\ 914 vY $ 30.00 I 27,4.>.>.20 C:v.....t lW ...,, I$ 4U.W $ 4,U11 . .ru , i=;n,o r........i1nr1 ~~,. Rnll Pr,,,,.,ration 83,836 l)t-I$ 0.501$ 41,9111.00 Sub-Total I 73......,,40 ,~ - Place 3" r.n ...tu.ti Rnrlr (67. llllR SFl 1,.!4.! l.iY 85.00 lUb,bfU,W ln•l"II 24" HOPE Pirie L<U Lt' fb.00 21, .JUU,00 RAl"AOVe anct WAP\1"21,.... ln•t"DH ~ .. --•,!linhl"lla. r:1V1A ~l"I ~---9 l:.A 3,:'JI.Jl,00 31,e>tJIJ,()() D..i.-.. p........,.,, 8,.,. .:,r-1.00 8,fNI,()() - ~ .. L -I $ 166,167.uu utr.NT-IJF-WUav PArmAnNlt -115,322 SF i$ 1.00 i I 115,.>ll.OO , .-Construction i:;,.,...,.,,..nl 73,!;)(1 ::;r-$ 0.50 $ 36,H;ib.50 Sub;i--•I I ,:u 1::,1.:IO I w..11 .. nn· · 1 Al.. $ :>154,WU.00 $ 4!lll,:>tJU,00 Sub-Total I ..,,:11K1.UIJ Total I$ -.uau.4U -25%1$ 249.u-.m, 10 r,t...,..,fTft••• $ 1,_,., lW,50 Table 16-Cost Comparison Summary Description Alternative 1 Alternative 2 Construction $325,467.00 $353,362.90 Easement Acquisition $113,550.50 $152,157.50 Environmental Mitigation $490,560.00 $490,560.00 25% Contingency $232,394.38 $249,020.10 Total= $1,161,971.88 $1,245,100.50 ~ CITY OF VISTA Dt,VID EVANS ASSOCIATES 9. Conclusion and Recommendation a. Conclusion and Recommendations When factoring in all relevant studies and constructability, we conclude that the preferred access road design is Alternative 1 (Exhibit 2). Although both Alternatives 1 and 2 (Exhibit 3) avoid highly, moderate, and unknown environmentally sensitive areas, Alternative 1 provides for a lower overall cost, more continual access with limited vehicle movements, and utilizes a portion of the previously recorded VCl sewer easement. The Alternative 2 cost is not significantly higher than Alternative 1 at a 5-percent increase, but the Alternative 2 layout is less efficient as it requires more maintenance vehicle movements due to individual spur roads and proposes permanent improvements on residential parcel 167-040-31-00. In addition to the two build alternatives, an evaluation of the City's existing equipment and research for new alternative equipment was performed to determine if there was an alternative to constructing new access roads or if the footprint of proposed improvements could be limited. Through our research and alternative analysis, it was determined that the City owns an extensive fleet which includes both full size as well as low impact (easement) equipment. Alternative equipment as discussed in Section 3d still requires full access or provides limited benefit. This along with the understanding of legal maintenance requirements set forth on purveyors as well as the City's goal of zero sanitary sewer overflows is the reason two build alternatives were developed providing the most cost effective options for continual all weather maintenance and emergency access. Benefits of Alternative 1 include the following: • Uses the existing access road alignment between Haymar Drive at the westerly project limits to just south of manhole 28 to minimize grading and impacts to undisturbed and environmentally sensitive areas. • Provides a direct improved spur road to manhole 27 which allows for all weather access. • Provides a proposed access road along the alignment of the recorded VCl sewer easement to provide all weather access to manholes 29 through 31. The use of recorded easement reduces the overall cost for acquiring new easements. • Following the recorded easement also minimized the grading limits as the alignment parallels much of the natural topography in that particular area. This reduces impacts to parcel 167-040-31-00 and undisturbed areas in parcel 167- 040-38-00. • Maintenance vehicles have a continual path with minimal turning movement for all manholes except manhole 27. Disadvantages of Alternative 1 include the following: ~ CITY OF VISTA Dt\VID EVANS ASSOCIATES • Following the recorded easement along the southerly property line of parcel 167- 040-31-00 results in increased grading impacts when compared to Alternative 2. • Constructing a new road from manhole 28 to manhole 31 in lieu of using the existing access road between the same two manholes results in additional vegetation clearing and earthwork. ~ CITY OF VISTA Appendix F Alternatives • DAV10 EVANS ASSOCIATES " .. LEGEND ----PROPERTY LINE --s ...ll'...llZ EXISTING SEWER =so...!££!! EXISTING STORM DRAIN EASEMENT LINE -----ENVIRONMENTAL STUDY LIMITS EXISTING ROAD EXISTING MANHOLE ~ ... :., -•· •~ lj:· )r-Jiiil.... !'liii.:~,,-.... / VC1 SEWER ACCESS EXHIBIT NO BUILD .. AVID ■VANa -Aaaoc1ATl!a '"°· 4200 Concours Sui:, 150 Ontario California 9f754 Phone: 909.481.5750 ll LEGEND ~-,....:...,,, =to.2!:..2! PROPERTY LINE EXISTING SEWER EXISTING STORM DRAIN EASEMENT LINE ENVIRONMENTAL STUDY LIMITS EXISTING ROAD EXISTING MANHOLE VC1 SEWER ACCESS EXHIBIT NO BUILD .. AVIDEVAN8 -AaaOCIATE8 ONO. 4200 Concours Suite 150 Ontario Calrfomia 91764 Phone: 909.481.5750 CONSTRUCTION NOTES 0 RECONSTRUCT EXISTING SEWER MANHOLE CONE AND RISER AND INSTALL LIGHTWEIGHT MANHOLE COVER PER CITY OF VISTA STD. DWG. SWR-33. 0 INSTALL CONCRETE COLLAR PER CITY OF VISTA STD. DWG. SWR-30A 0 INSTALL CONCRETE COLLAR PER CITY OF VISTA STD. DWG. SWR-30C. LEGEND ~ PROPOSED 3" CRUSHED ROCK 15' · I 12· Lu: ----PROPERTY LINE --,~ EXISTING SEWER =so 24"RI' EXISTING STORM DRAIN -----EASEMENT LINE -----ENVIRONMENTAL STUDY LIMITS EXISTING ROAD --+-·-CUT/FULL & DAYLIGHT LINE EXISTING MANHOLE 1d' ACCESS I TYPICAL SECTION SEWER ACCESS ROAD z <( ...J OCl.. '3 a:: I--. "<;( a::W~ ~'!11-JHi!,.~' ~ ~ . ' C • lM'A,ll;}. .., uJ .· ~~ . .-. ·B z 0 u DETAIL TYPICAL MANHOLE ACCESS PLAN VIEW z :5 C CI.. <( oa:: a::W Cl.. ~V) WW u:::> uz < F z 8 VC1 SEWER ACCESS EXHIBIT ALTERNATIVE 1 .. AVID ■VANa ...... AaaDCIATl!a ·-· 4200 Concours Suh..~ 150 Ontario California gj;,54 Phone: 909.481.5750 PROPOSED 3" CRUSHED ROCK ----PROPERTY LINE --• --EXISTING SEWER =•= EXISTING STORM DRAIN -----EASEMENT LINE -• ---ENVIRONMENTAL STUDY LIMITS --------EXISTING ROAD --_,--· -CUT/FULL & DAYLIGHT LINE o EXISTING MANHOLE CONSTRUCTION NOTES 0 RECONSTRUCT EXISTING SEWER MANHOLE CONE AND RISER AND INSTALL LIGHT'I\IEIGHT MANHOLE COVER PER CITY OF VISTA STD. DWG. SWR-33. 0 INSTALL CONCRETE COLLAR PER CITY OF VISTA STD. DWG. SWR-30A. 0 INSTALL CONCRETE COLLAR PER CITY OF VISTA STD. DWG. SWR-30C. VC1 SEWER ACCESS EXHIBIT ALTERNATIVE 1 .. AVID EVAN■ -A■■OCIATE■ 1""· 4200 Concours Suite 150 Ontario California 91764 Phone: 909.481.5750 CONSTRUCTION NOTES CD RECONSTRUCT EXISTING SEWER MANHOLE CONE AND RISER AND INSTALi LIGHTWEIGHT MANHOLE COVER PER CITY OF VISTA STD. DWG. SWR-33. 0 INSTALL CONCRETE COLLAR PER CITY OF VISTA STD. DWG. SWR-30A. 0 INSTALL CONCRETE COLLAR PER CITY OF VISTA STD. DWG. SWR-30C. LEGEND !™-~ PROPOSED 3" CRUSHED ROCK PROPERTY LINE --• ...a:...,sz EXISTING SEWER ="~ EXISTING STORM DRAIN -----EASEMENT LINE • • • • • ENVIRONMENTAL STUDY LIMITS EXISTING ROAD --t--· -CUT/FULL & DAYLIGHT LINE •'"' EXISTING MANHOLE Ll'. 12' -m-m- % ·6" THK 3" CRUSHED ROCK TYPICAL SECTION SEWER ACCESS ROAD z :'.i oa.. ~ ffi ~--. •. ~~;i:;6_~-: . -. "§,_~ -~~ tJ ~:rY. ct .. 'I-' _,. };iSJ.J:l:J;JSlj ~!. . .. - DETAIL z 0 u TYPICAL MANHOLE ACCESS PLAN VIEW z :'.i oa.. <( oa:: a::W a.. ~Ill wW u=> uz <( ~ z 0 u VC1 SEWER ACCESS EXHIBIT ALTERNATIVE 2 .. AVID ■VANa -.-.eeoc1ATEa •-· 4200 Concour., Sui~ 150 Ontario Califomia ~764 Phone: 909.481.SJSO ~