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Wastewater Treatment Plant Master Plan Vol. 2- 2000CITY OF PISMO BEACH WASTEWATER COLLECTION SYSTEM MASTER PLAN The City of Pismo Beach Wastewater Collection System Master Plan was prepared under the direction of the following registered Civil Engineers: Prepared by: Robert S. Miller, P.E. Senior Engineer an Approved by: Johrfy. Wallace, P.E. Prin ipal Engineer ~Cv0'p, S. No.CD 57474 f� g4 C TABLE OF CONTENTS CHAPTER PAGE NUMBER 1 EXECUTIVE SUMMARY 1.1 Introduction 1-1 1.2 Purpose and Scope 1-1 1.3 Findings of Collection System Master Plan 1-1 1.4 Collection System Upgrade Recommendations 1-3 2 INTRODUCTION 2.1 Purpose 2-1 2.2 Scope of Study 2-1 3 LAND USE AND POPULATION 3.1 Land Use and Population 3-1 3.2 Growth Rate Analysis 3-1 4 WASTEWATER FLOWS 4.1 Existing Wastewater Flows 4-1 4.2 Peaking Factor Analysis 4-4 4.3 Future Wastewater Flows 4-5 5 INFILTRATION 1 INFLOW ANALYSIS 5.1 Historical Analysis 5-1 5.2 Flow Monitoring Program 5-1 5.3 Supplemental Testing 5-6 5.4 Analysis of Results 5-6 6 WATER COLLECTION SYSTEM ANALYSIS 6.1 Existing Collection Facilities 6-1 6.2 Collection System Modeling 6-1 6.3 Gravity System Analysis and Deficiencies 6-6 6.4 Lift Station Analysis and Deficiencies 6-11 6.5 Odor and Corrosion Control 6-23 7 WATER COLLECTION SYSTEM OPERATIONS 7.1 Collection System Maintenance 7-1 7.2 Staffing Levets 7-1 8 RECOMMENDATIONS AND CAPITAL IMPROVEMENTS 8.1 Recommendations 8-1 8.2 Capital Improvement Program 8-1 LIST OF TABLES TABLE NUMBER AND NAME PAGE. NUMBER 1-1 Summary of Design Flows 1-1 1-2 Priority 1 Capital Improvements 1-3 1-3 Priority 2 Capital Improvements 1-4 1-4 Priority 3 Capital Improvements 1-4 3-1 Existing and Future Land Use and Population 3 2 3-2 Summary of Proposed Sphere of Influence Modifications 3-2 4-1 Existing Average Annual Flows by Land Use 4-1 4-2 Summary of Existing Flows by Tributary Area 4-3 4-3 Summary of Peaking Factor Analysis 4-4 4-4 Future Wastewater Flows 4-5 4-5 Summary of Future Flows by Tributary Area 4-6 5-1 1998/99 Flow Comparison 5-2 5-2 Estimated Cost of III Elimination 5-6 5-3 Capital Cost Benefits of III Reduction 5-7 6-1 Sewer Collection System Inventory 6-1 6-2 Existing Lift Station Summary 6-2 6-3 Cost Benefit Summary - Proposed Force Main Realignment 6-9 6-4 Additional Gravity Collection System Deficiencies 6-11 6-5 Addie Street Lift Station Summary 6-13 6-6 Five Cities Lift Station Summary 6-14 6-7 Pismo Oaks Lift Station Summary 6-15 6-8 Freeway Foothills lift Station Summary 6-16 6-9 Vista Del Mar Lift Station Summary 6-18 6-10 Spyglass Lift Station Summary 6-19 6-11 PG&E Lift Station Summary 6-20 6-12 Saint Andrews Lift Station Summary 6-21 6-13 Sunset Palisades Lift Station Summary 6-22 7-1 Estimated Collection System Maintenance Requirements 7-1 8-1 Priority 1 Capital Improvements 8-2 Priority 2 Capital Improvements 8-3 Priority 3 Capital Improvements 8-1 8-2 8-3 11 LIST OF FIGURES FIGURE NUMBER AND NAME PAGE NUMBER 3-1 Residential Growth Rates 3-3 4-1 Summary of Lift Station Collection Areas 4-2 5-1 Flow Meter Results - Pismo Heights 1 Downtown 5-4 5-2 Flow Meter Results - Pismo Heights 5-5 6-1 Existing Facilities - Shell Beach 6-3 6-2 Existing Facilities - South Pismo Beach 64 6-3 Existing Facilities - Downtown Area 6-5 6-4 Capital Improvements Plan 6-7 6-5 Capital Improvements Plan 6-8 8-1 Implementation Schedule: Priority 1 Capital Improvements 84 TECHNICAL APPENDICES Appendix A: Gravity Computer Model Results - Separate Volume Appendix B: Pressure Computer Model Results - Separate Volume Appendix C: Budget Cost Estimates Appendix D: Flow Monitoring Results - Separate Volume ui Wastewater Collection System Master Plan - Chapter 1 EXECUTIVE SUMMARY 1.1 INTRODUCTION The Pismo Beach Wastewater Collection System consists of gravity sewers, nine lift stations, and force mains which convey raw wastewater to the WWTP. Due to the entry of extraneous storm water into the collection system and the lack of adequate capacity, overflows have occurred at several lift stations during periods of intense rainfall. The majority of the overflows have occurred at the Addie Street lift station, which conveys approximately two-thirds of the total City wastewater flow. In addition, recent flow records indicate that the existing 12" interceptor sewer which conveys wastewater from the Shell Beach area flows nearly full under existing peak summer conditions. In summary, additional capacity, reliability, and redundancy is recommended for the wastewater collection system. 1.2 PURPOSE AND SCOPE The purpose of the Wastewater Collection System Master Plan is to furnish a comprehensive program of prioritized capital improvements which will address existing deficiencies and provide adequate collection system capacity and redundancy consistent with the ultimate needs of the City. An executive summary of the findings and recommendations is presented below. 1.3 FINDINGS OF COLLECTION SYSTEM MASTER PLAN Design Flows and Wastewater Characteristics Table 1-1 presents a summary of the design wastewater flows. Table 1-1 Summary of Design Flows Design Year 1998 2016 (Build -out) Population, persons 8,528 14,438 Hotel Rooms 1,831 3,119 Commercial, sq. ft. 953,600 1,602,000 RV Park, spaces 811 821 Flow, mgd Average Annual (AAF) 1.2 2.0 Peak Day Dry Weather (PDF) 1.76 3.0 Average Day Maximum 1.26 2.4 Month Dry Weather Flow Peak Hour Wet Weather 3.14 6.0 1-1 Infiltration 1 Inflow Analysis During periods of intense rainfall, wastewater flows at the WWTP have periodically tripled due to the entry of extraneous storm water into the system. Collection system overflows have also resulted from the high storm -related peak flows. During the period of January through March, 1999, the City maintained a system of flow meters with the intent of isolating the infiltration / inflow (1/1) problem to smaller sub -areas of the system. Rainfall during the monitoring period was light by historical standards. The largest storm occurred on March 15, when approximately 1.2" of rain was recorded at the WWTP. System -wide I/1 was small during this event, and flow remained at average levels at the WWTP. Even with the light rainfall, the metering program was successful in identifying a major contributor to the 1/1 problem - the Pismo Heights. During the period analyzed, the Pismo Heights contributed more than 80% of the total estimated 1/1 reaching the WWTP. In addition, it is anticipated that subsequent attempts to eliminate 1/1 from the Pismo Heights will be cost effective when compared with the capital expense of upgrading the downstream facilities to adequately convey extraneous storm flows. Gravity Collection System A hydraulic computer model was prepared for the gravity collection system to analyze system performance under existing and future conditions. Based on the results of this analysis., several existing and future gravity system deficiencies were noted. The existing interceptor which conveys wastewater more than 2 miles from the Shell Beach area to the Addie Street lift station is undersized for both existing and future peak flows. It is recommended that the City bypass the interceptor with a 12" force main from Shell Beach to the WWTP. Future flow deficiencies were also noted upstream of the Pismo Oaks and Vista Del Mar lift stations. Replacement of gravity sewers is recommended for these locations. Sewer Lift Stations A separate computer model was developed to analyze the nine lift stations and associated force mains. Each station was analyzed for deficiencies, and improvements of varying priority were recommended for all nine stations. The Addie Street lift station has been in operation for 44 years, and replacement of the station is warranted due to capacity, redundancy, odor, and age -related deficiencies. Due to its critical role in the collection system and historical overflow problems, the Addie Street lift station replacement project was given a higher priority than the other lift station improvements. For the remaining eight lift stations, various upgrades to existing infrastructure are recommended. In accordance with the Facilities Element of the City General Plan, all lift stations should ultimately have stand by power. In addition, connection facilities to accommodate a trailer -mounted pump station, such as the unit recently purchased by the City, should be added to each lift station. The Sunset Palisades lift station is the only exception to this recommendation, where discharge pressures exceed the capacity of the trailer -mounted unit. 1-2 1.4 COLLECTION SYSTEM UPGRADE RECOMMENDATIONS The Collection System Master Plan consists of staged capital improvements to correct existing deficiencies and provide for the ultimate City needs. The following tables summarize a three stage capital improvement program which reflects the relative importance and recommended timing of the projects. Priority 1 improvements should be constructed within the next 5 years. Priority 2 improvements should be completed in the next 5 to 10 years, and Priority 3 improvements should be implemented in 10 to 15 years. The total cost of the recommended collection system improvements is $2,861,000. Table 1-2 Priority 1 Capital Improvements Budget Cost No. Project Name Description Estimate 1-1 Shell Beach force main Bypass the existing interceptor with a See Note 1 relocation new 12" force main to the Addie Below Street L.S. force main. 1-2 Pismo Heights 111 Reduce Ill in the Pismo Heights area $50,000 Elimination by contacting residents and repairing leaks. 1-3 Addie Street lift station Construct a new submersible lift $800,000 replacement station facility at Addie Street 1-4 Pismo Oaks lift station Upgrade the Pismo Oaks L.S. to $300,000 upgrade correct structural, capacity, and operational problems 1-5 Interceptor manhole Coat interceptor manholes with a $140,000 rehabilitation sulfide -resistant product 1-6 Five Cities lift station Upgrade the Five Cities L.S. with new $310,000 upgrade pumps and stand by power. Replace the existing 6" force main with an 8". 1-7 Park/Cypress gravity Combine the three existing lines into a $355,000 sewer improvements common 18" sewer with additional depth. Divert flows as summarized in Chapter 6. TOTAL OF PRIORfTY 1 IMPROVEMENTS (CCI = 7000) $1,955,000 Notes: 1. As a result of the draft Master Plan report published in June, 1999, the Shell Beach force main relocation project was funded for the 99/00 fiscal year in the amount of $1,120,000 and therefore does not appear in the table. 1-3 Table 1-3 Priority 2 Capital Improvements Budget Cost No. Project Name Description Estimate 2-1 Vista Del Mar lift station Upgrade the Vista Del Mar L.S. to $166,000 upgrade correct capacity & operational issues 2-2 Freeway Foothills lift Upgrade the Foothill Freeway lift $80,000 station upgrade station to correct operational problems and add stand by power. 2-3 St. Andrews lift station Add stand by power and upgrade $50,000 stand by generator & electrical system electrical upgrades TOTAL OF PRIORITY 2 IMPROVEMENTS (CCI = 7000) $296,000 Table 1-4 Priority 3 Capital Improvements Budget Cost No. Project Name Description Estimate 3-1 Sewer sag repair adjacent Correct existing sag with new 8" $62,000 to Pismo Pier sewer. 3-2 Spyglass lift station Upgrade the Spyglass lift station to $110,000 upgrade add stand by power and correct operational deficiencies 3-3 PG&E lift station stand by Add stand by power $24,000 generator 3-4 Sunset Palisades lift Add stand by power See Note 1 station stand by generator Below 3-5 Vista Del Mar gravity Replace existing 8" sewer with a 10" $114,000 system upgrade sewer to prevent system surcharging 3-6 Pismo Oaks gravity Replace the existing 10" sewer with a $300,000 system upgrade 12" -sewer to meet future capacity requirements TOTAL OF PRIORITY 3 IMPROVEMENTS (CCI = 7000) $610 000 TOTAL OF ALL IMPROVEMENTS (PRIORITY 1, 2 & 3) $21861,000 Note: 1. As a result of the draft Master Plan report published in June, 1999, a dedicated mobile generator was funded for the 99100 fiscal year and therefore a cost for this item does not appear in the table. 1-4 Wastewater Collection System Master Plan - Chapter 2 INTRODUCTION 2.1 PURPOSE The City of Pismo Beach supplies its customers with wastewater collection, treatment, and disposal services. The current City population of approximately 8,500 is expected to increase to 13,000 at build -out of the existing City limits. An additional 1,438 persons is anticipated due to potential modifications in the City Sphere of Influence for a total population of 14,438. As the City corrects current capacity and age -related problems with the system infrastructure, it is the City's intent to construct wastewater system improvements consistent with the ultimate needs of the system. In order to facilitate this goal, the City has elected to prepare a comprehensive Wastewater Master Plan. 2.2 SCOPE OF STUDY The City contracted with Carollo Engineers P.C. (Carollo) and John L. Wallace & Associates (JLWA) to prepare a comprehensive Wastewater Master Plan that would evaluate the existing wastewater collection and treatment system and recommend a program of improvements in order to provide for a well -planned and comprehensive program. JLWA is preparing the collection system portion of the report. The scope of the collection study includes the following: Review the Land Use Element of the City General Plan and coordinate with City planning staff to determine potential annexations within a 20-year planning horizon. 2. Estimate the current and projected average and peak wastewater flows for the treatment system and for individual elements within the collection system. 3. Under a separate JLWA contract with the City, conduct an Infiltration/inflow analysis to determine the sources of storm water intrusion into the system. This analysis includes field testing such as flow monitoring and physical inspections performed during the period of January, 1999 through April, 1999, 4. Prepare an economic analysis comparing the estimated cost of removing the infiltration/inflow to the expense of conveying and treating the additional flow. 5. Prepare a comprehensive computer model of the collection system, including both the gravity and pressure systems. Analyze the collection system in terms of existing and future deficiencies. 8. Using the City-fumished system information, prepare computer -generated mapping of the collection system for the study and atlas. 7. After analyzing each sewer lift station and force main, recommend improvements to be performed within the 20 year planning horizon. 8. Recommend improvements to the gravity collection system to be performed within the 20 year planning horizon. 2-1 9. Analyze the sources of odor and corrosion within the collection system and recommend methods of mitigation. 10. Review the adequacy of current and future operator staffing levels. 11. Estimate the budget cost of each recommended improvement to the collection system. 12. Prepare a prioritized capital improvement program for implementation of the recommended system modifications. 2-2 W Wastewater Collection _S sy tem Master „Plan - Chapter 3 LAND USE AND POPULATION 3.1 LAND USE AND POPULATION The City of Pismo Beach is located in the Southern portion of San Luis Obispo County and stretches along the Pacific shoreline some seven miles. The City currently serves an estimated population of 8,528 persons. The dominant economic activity in Pismo Beach is tourism, and as a result the population of the City can more than double during summer holidays. The Land Use zones within the City are established by the Land Use Element (LUE) of the General Plan & Local Coastal Planning, which was last updated in 1992. The General Plan predicts a build -out population for the City of 13,000 persons and establishes a maximum allowable growth rate of 3% per year. This ultimate population includes the annexation of areas within the Sphere of Influence, or probable future City limits. In addition to our review of the General Plan, JLWA coordinated with City planning staff to determine the following: Pending or proposed changes to the Sphere of Influence. Status of proposed annexations within the existing Sphere of Influence [ref. 2]. Growth patterns and residential development occurring after the 1992 General Plan Update. When the proposed changes to the Sphere of Influence are included within the future population estimate, the build -out population increases to 14,438 persons. Table 3-1 below summarizes the existing and future land use patterns within the City by development type. More detailed zoning designations are available for each type of land use. However, the general categories identified in the table are useful for the estimation of future wastewater flows. 3.2 GROWTH RATE ANALYSIS The Growth Management Element of the General Plan stipulates a maximum growth rate of 3% for the City. Since the preparation of the General Plan in 1992, growth has been at a slower rate, with an average value of 1 %. However, given the current economic conditions in the area, higher growth rates are expected to persist in the near future. As an example, more building permits were issued in 1998 than in any year since 1991. It will be assumed for the purposes of the master plan that the growth rate will approach 3%, and therefore the City will be completely built -out by the year 2013 within the existing Sphere of Influence. If the proposed modifications to the Sphere of Influence are included, the City will be completely built -out by the year 2016. Figure 3-1 summarizes residential development within the City in terms of growth rate. 3-1 Table 3-1 Existing and Future Land Use and Population Future Uses Development Description Existing Uses (1998) (within current Sphere) Residential Dwelling Units 5,446 units 6,896 units Residential Population (Used 8,528 persons 13,000 persons for flow estimates) Commercial 953,600 square feet 1,602,000 square feet Hotel Rooms 1,831 rooms 3,039 rooms RV Parks 811 spaces 821 spaces Proposed Sphere of Influence Modifications Residential Dwelling Units -- 575 units Residential Population -- 1,438 persons Hotel Rooms -- 80 rooms Table 3-2 provides additional detail concerning proposed modifications to the City Sphere of Influence (SOI). For the purposes of this report, design wastewater flows for the WWTP and the collection system include the proposed SOI modifications. The additional wastewater capacity required to accommodated the proposed SOI modifications is not expected to increase capital improvement costs by more than 5%. Even if the SOI amendments do not occur, the additional capacity will allow for fluctuations in water demand, tourism, and commercial :use and will provide the City with increased flexibility at a low incremental cost. Table 3-2 Summary of Proposed Sphere of Influence Modifications Project Name Dwelling Hotel 1 Comments Units Motel Units Los Robles Del Mar 298 0 This dwelling unit projection is included in the build -out population of 13,000 due to its dwelling unit allocation specified in the GP/LCP Cottonwood area 600 0 The Preserve 75 80 - The Ranch 153 460 RV's The applicant is proposing an independent wastewater treatment and collection system, therefore this project is not included in the flow estimates. 3-2 a) � CO Z G \\� W U N O U (/) L v \ (L ` aLO LL.LLI ---- - -- - -- (V O'7 z W �w ,` U Q II CO LV < L — — — — �" — — — — — Njr CL CD `— i/7 CV w\ \ O ` O LL. O O T Q j Q (� N N 000 M m r O x >l i LLJ \ L O >a O O_ N >. O C)ci O) ;3 C`j N 1 M it p — — — — - — — — — — N c , 1 � C3 — — — — — — — Ln pp — — — — 1 N 1 \ [f) CD 1 cp11 1 1 1 1 T - p Q,, `M 1 1 1 Q) T O co T O tf) T O ll;r T O M T O N r Q r r O O T O Co CO G l+ uoijoindod 1e11uapisaa �M Wastewater Collection System Master Plan - Chapter 4 ATER FLOWS 4.1 EXISTING WASTEWATER FLOWS Historical wastewater flows were examined throughout the City collection and treatment system by utilizing the following sources of data: Wastewater Treatment Facility (WTF) flow records Lift station flow data Flow meter data associated with the infiltrationAnflow study Table 4-1 summarizes the estimated wastewater generation characteristics of various existing development types within the City. The flow factors employed in Table 4-1 were derived from a variety of sources including the Facilities Element of the General Plan, corresponding data from similar communities, and water use information. Table 4-1 Existing Average Annual Flows by Land Use Source of Flow Quantity Flow Factor (galldaylunit) Total Average Annual Flow (gal/day) Residential 8,528 Persons 95 810,160 Hotel Rooms 1,831 rooms 100 183,100 Commercial 953,600 sf 0.10 95,360 RV Park 811 50 40,550 Public Facility NIA 20,000 20,000 Infiltration/Inflow NIA 35,000 35,000 1998 AVERAGE ANNUAL FLOW 1,184,170 -1.2 mgd In addition to City-wide flows, tributary flows to each wastewater lift station and sub -area within the City are also critical to the system. analysis.. Figures 4-1 displays the tributary areas for each lift station, and Table 4-2 summarizes the existing land use characteristics and wastewater flows by sub -area. A discussion of system peaking factors is included below. Each sewer lift station is described and analyzed in additional detail in Chapter 6. 4-1 M SiJNSET PALSSADES� / LLFr STATION ❑LIFT STATION / EI INILNDREWS J / STATION ®* VISTA DEL MAR J LLFI' STATrON� 1" = 20OU 0 500 1000 2000�.1"'� k FOOTHILL. FREEWAY El IF F STATION PR fc Olcearl *NOTE: THE ADDLE STREET LIFE STATION CURRENTLY RECEIVES ALL SHELL BEACH FLOW. IN THE John L. Wallace & Associates _ FUTURE, ONLY THE FREEWAY FOOTHILLS AREA WILL CONTRIBUTE TO ADDIE STREET FROM SHELL BEACH. �-7 / J� O``� ADDLE _ _ �' O �r STATION *See Note / / / / 9 FIVE CITI S_ TTPT STATTON e CITY OF PISMO BEACH Wastewater Master Plan Figure 4-1 City of Pismo Beach Summary of Exists Lift Station Collection Areas THE HEIGHTS_ _ _ COLLECTION AREA wN, PG&E i PLSMO OAKS F7 -`IVP STATION L 4.2 PEAKING FACTOR ANALYSIS In order to appropriately design wastewater treatment and collection facilities, peak flow conditions must be quantified. The "peak" conditions of interest for facility design are summarized below: Average Annual Flow (AAF) is obtained by dividing the total flow conveyed by the City system in one year by 365 days. Other peak conditions are derived by multiplying the AAF by a peaking factor (PF). The flow factors in Table 4-1 reflect average annual usage. Peak Day Dry Weather Flow (PDF) is the maximum flow occurring in one day during the dry season. In the City of Pismo Beach, this condition normally occurs during the Fourth of July weekend. Peak Hour Wet Weather Flow (PHWWF) is the maximum flow rate that occurs in a single hour during wet weather. Infiltration and inflow contributes a substantial amount to this flow rate at the City of Pismo Beach. Average Day Maximum Month Dry and Wet Weather Flows reflect the maximum flow rate during the peak months of summer and winter, respectively. Table 4-3 summarizes the historical and projected peaking factors for the entire City. The variations in residential wastewater flow become more pronounced as smaller areas are examined. For example, the Sunset Palisades lift station currently serves an estimated population of 769 persons. Given the small contributing population, the City-wide peaking factor for Peak Hour Wet Weather Flow (3.0) would not be appropriate for design. Based on meter data at the City and studies of similar sewer collection systems, a peaking factor of 4.0 plus an allowance for infiltration/inflow would be appropriate. Tables 4-2 and 4-5 use this method to calculate PHWWF for the design of individual lift stations. Table 4-3 Summary of Peaking Factor Analysis 1998 Historical Design Peak Flow Condition Flows Peaking Factor Peaking Factor (mgd) (City -Wide) (City -Wide) Average Annual Flow (AAF) 1.2 -- -- Peak Day Dry Weather Flow (PDF) 1.76 1.49 1.5 Peak Hour Wet Weather Flow 3.14 2.67 3.0 (PHWWF) Average Day Maximum Month Dry 1.26 1.07 1.2 Weather Flow Average Day Maximum Month Wet 1.59 1.35 1.35 Weather Flow 4-4 4.3 FUTURE WASTEWATER FLOWS Table 4-4 summarizes the future wastewater flows for the entire City at build -out using the peaking factors and land use analysis previously described. Table 4-5 summarizes build -out wastewater flows for individual sub -areas and lift stations. Table 4-4 Future Wastewater Flows Flow Condition City Wide Peaking Factors Build -out Wastewater Flows (mgd) Average Annual Flow (AAF) -- 2.0 Peak Day Dry Weather Flow (PDF) 1.5 3.0 Peak Hour Wet Weather Flow (PHWW) 3.0 6.0' Average Day Maximum Month Dry Weather Flow 1.2 2.4 Average Day Maximum Month Wet Weather Flow 1.35 2.7 Notes: 1. The future estimate of 6.0 mgd includes 2.0 mgd of stom7 water inflow. 4-5 .... m m - m wr� N 1, u0'� U.) N'r O m N c M M� m�s N � M N O 0 ti f0 m +_ H 11 r T d 3 _ o w O �r O. co CA J C U): d a T N v W �+ T Ln 0) m Lo V (0 m N r i- m 7� CO 0) M V � m m ti N m 4 v N N fcr7 a r N N to� O � c = d ` � a vi cm .� y -- 0 MO 0 0 W 000 0 0 0 0000 0 0 0 0 000000 0 0 0 C 0 0 00 0 0 0000 0 0 0 IIl Co 3 is 1- r OD 0) r v F- n co m Ln CO rW G N v fs Lf) 01 m C is LO 7 w m ti r t: C. 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LL H w M '0 (A^� M+_+ '0 to 0 m c W E J CL i O Jm 0LO 40 � fl U to O IC -le y 'i d Q C=O U 3 LLJ o IL 41 — Ll y i m .� (� Z (' N O O H d > w O .0 cnm ado �a{70 mama ff a{� wiiaUf- �N y �- a 0 0 Wastewater Collection INFILTRATI 5.1 HISTORICAL ANALYSIS Master Plan - Chapter 5 LOW ANAL The City of Pismo Beach wastewater system historically experiences high peak flows during periods of wet weather as a result of infiltration and inflow (1/1). For the purposes of this report, these terms are defined as follows: Inffltration is the water entering a sewer system and service connections from the ground, through such means as, but not limited to, defective pipes, pipe joints, connections, or manhole walls. Infiltration does not include inflow. Inflow is the water discharged into a sewer system and service connections from such sources as, but not limited to, roof leaders, cellar, yard and area drains, foundation drains, cooling water discharges, drains from springs and swampy areas, manhole covers, cross connections from storm sewers, catch basins, storm water, surface runoff, or drainage. Inflow does not include infiltration. Infiltration is typically constant over a period of days, weeks, or even months. Inflow varies rapidly with rainfall conditions, with flows rising and falling within minutes or hours of a severe storm event. Driven by El Nino conditions prevalent in the Pacific Ocean, total rainfall during the early months of 1998 exceeded average levels by a factor of two in many areas of San Luis Obispo County. The City of Pismo Beach wastewater treatment facility experienced record flows during the period, with a February peak of 2.6 mgd and an elevated February average of 1.59 mgd. According to operations staff, flows rose within minutes of intense rainfall, leading staff to the conclusion that inflow was the primary problem. A number of spills resulted from the high flows, primarily centered around Addie Street. As a result of this condition, the City contracted with JLWA to prepare an Ill study for the system. This chapter highlights the results of the flow monitoring program and supplemental testing. In addition, the cost effectiveness of eliminating known sources of Ill is examined. 5.2 FLOW MONITORING PROGRAM As part of the 1/1 study, flows were monitored at 11 locations throughout the City from the period of January, 1999 through March, 1999. Data was collected from two primary sources as follows: Lift Station data:. An automatic.control system.at each of the nine lift stations in the City continuously calculates station flow at less than 10 minute intervals. This program provided continuous data at nine sites. Portable flow meters: Two portable area -velocity flow meters were utilized in tandem to "track" flows upstream in the gravity areas of the City. These meters were configured to record flow at 10 minute intervals. 5-1 In comparison to the first months of 1998, inflow -related flows to the treatment plant during the 1999 metering period were small to negligible. Table 5-1 illustrates this key observation for the months of January and February: Table 5-1 1998/99 Flow Comparison Flow Condition WWTF Flows in mgd Jan. 199 Feb. `99 Jan. `98 Feb. `98 Average Monthly Flow 1.00 1.03 1.11 1.50 Maximum Daily Flow 1.21 1.24 11 1.50 2.62 Peak Hourly Flow -- 2.51 11 2.79 3.14 In 1998, rainfall totals in excess of 1" in 24 hours were commonplace, and totals in excess of 2" in 24 hours occurred. In the first months of 1999, only one rainfall event exceeded 1" in 24 hours. This event occurred on Monday, March 15, 1999, when a total of 1.17" was recorded at the WWTF. In addition, flows at the WWTF during this rainfall event remained near average levels, with a total flow for the day of 1.01 mgd. Given the minimal rainfall totals and the negligible inflow levels at the WWTF, the results of the flow metering program could have been inconclusive. Fortunately, one portable flow meter recorded an obvious flow spike during a short rainfall event on January 31, 1999. The meter was installed on the existing 8" line at the intersection of Cypress and Stimson streets. This line serves the easterly half of the downtown area and the Pismo Heights. Approximately 0.60' of rainfall fail during the off-peak hours of 2:00 to 4:00 AM, when domestic flows are consistently at minimum levels. Figure 5-1 shows the meter results for Sunday, January 31 superimposed on the previous day with an obvious spike in flow. With the exception of Addie Street, all other sites showed negligible inflow. After analyzing the data for January 31, the Pismo Heights area was suspected as the most likely source of the inflow. The Pismo Heights collection system contains approximately 20,000 feet of 6" sewer pipe, with the majority of the system installed prior to the 1950's. This steep hillside community provided a likely source of illegal storm drain connections for the following reasons: When the system was installed, sewer system standards regarding the connection of roof leaders, foundation drains, and other inflow sources were either not as stringent or were non existent. The underground storm system is very minimal, leaving residents with fewer options to convey storm flows from area drains and roof leaders in a non -erosive manner. Individual backflow prevention devices and sump pumps are common due to the steepness of the terrain, making the system difficult to smoke test effectively. 5-2 The portable flow meters were moved upstream to isolate only the Pismo Heights area, and visual manhole inspections were conducted during subsequent storms. Field observations revealed that the flow spike recorded on January 31 did originate from the Heights. Figure 5-2 displays a flow record of Monday, March 15, 1999 superimposed over a more typical Monday (March 8, 1999). The meter was measuring flows from the Pismo Heights only. Other metering sites in the City showed only small to negligible changes in response to the rainfall. It is estimated that 150,000 gallons of excess storm water entered the system from the Pismo Heights area, which represents over 80% of the total estimated inflow for March 15. Field observations of the Pismo Heights system during rainfall revealed flooded manhole covers, areas of probable inflow entry, and .surcharged.conditions. One manhole just upstream of Jutkins Middle School was surcharged an estimated 2 feet over the top of the 6" sewer pipe. Given these results, supplemental testing was scheduled for the Pismo Heights area. Inflow in Other Areas of the City Based on the metering program, it can be concluded that the Pismo Heights system contributes a high proportion of the inflow into the system. However, it is likely that other areas of the City such as Shell Beach and the Pismo Marsh (Five Cities Lift Station tributary area) contribute inflow in exceptionally wet years and during larger storms, even though these areas exhibited minimal inflow in 1999. Therefore, it is recommended that flow monitoring efforts continue in subsequent years to confirm the adequacy of other areas in the City. This recommendation is consistent with regulatory requirements, in that an on -going program of Ill monitoring is also required in the draft update of the City NPDES Discharge Permit. Infiltration Infiltration of groundwater remained at low levels during the metering period. The major contributor of infiltration appears to be Shell Beach, where deep gravity collection systems are subject to high groundwater levels. Manhole inspections by City staff in February/March of 1998 revealed a number of leaks, some of them substantial. However, based on meter data from the Shell beach area, 1999 infiltration was less than 40 gal/min (57,600 gal/day) for Shell Beach. This calculates to an average rate of approximately 550 gpd / in -mile of sewer pipe, which is within acceptable limits. In contrast, the inflow recorded from the Pismo Heights calculates to nearly 10,000 gpd I in -mile of sewer line. Given the low to moderate levels of infiltration from the Shell Beach area, it is not cost effective at this time to eliminate infiltration sources. This recommendation should be carefully revisited during wet years, where 1/1 from the Shell Beach area could be more substantial. S-3 LL i, CD r= T r• ti {-• cc rr:.. *�. ....... ;a . •. C to m E `'- ai - - Q �• . c o m s f r- LO O Q ci Q N N ui� cc (UIW/185) M01.1 1 .r CD C! 04 L : � cc > � v on .r '.. N T •+ o � r .. ...... . ....... .T Pb .r' I {L r' O LO O LO O U) O kn M M N N + r (ulw/jes) Mold 5.3 SUPPLEMENTAL TESTING Smoke testing is one of the industry standard methods for locating sources of storm water inflow within a collection system. Smoke is introduced into a sewer manhole and forced into the system by a blower mechanism. The smoke is discharged to the atmosphere through all available vent points including residential sewer vents and manhole covers, but also through illegal connections such as connected area drains or roof downspouts. The Pismo Heights system was smoke tested on April 12, 1999. Smoke testing was difficult due to the presence of backflow devices, sump pumps, and older laterals with possible sags; all of which do not allow the passage of smoke. Approximately one third of the residences did not exhibit any discharge of smoke from the sewer vents. If these residences have illegal connections, smoke testing will not reveal them. In spite of the difficulties, smoke testing is still a critical first step and did yield some results, including a number of connected area drains. With the problem narrowed to the Pismo Heights, it is recommended that the City employ further investigation methods as follows: Contact individual home owners and conduct subsequent on -site inspections. Once staff has access to a residence, die testing and/or flood testing can be employed to verify the presence of storm water connections. Conduct a video camera investigation of the Pismo Heights. 5.4 ANALYSIS OF RESULTS Based on the metering program and supplemental testing, a 50% reduction in storm water inflow from the Pismo Heights appears possible. The costs associated with this reduction are summarized in Table 5-2: Table 5-2 Estimated Cost of I/l Elimination Method of Elimination Estimated Budget Cost Video inspection and survey of individual residences $25,000 Enforcement and tracking of inflow elimination $5,000 Supplemental flow monitoring to confirm inflow reduction $7,000 Repair/sealing of manhole frames and covers subject to flooding $5,000 Miscellaneous leak repairs $8,000 TOTAL ESTIMATED COST $50,000 5-6 The cost benefits associated with a 50% reduction in storm water inflow are substantial. In addition to the energy and chemical costs associated with the conveyance of storm water. Table 5-3 describes the anticipated capital cost benefits associated with the proposed reduction. Table 5-3 Capital Cost Benefits of Ill Reduction Description of Capital Cost Savings Estimated Savings Reduced pump, wet well, and electrical system size at Addie Street $12,000 Reduced gravity system improvements in the downtown area $50,000 Elimination of gravity system upgrades in the Heights to avoid surcharged flow conditions $30,000 TOTAL ESTIMATED COST $92,000 In summary, it is recommended that the City expediently transition from the exploratory mode of the Ill study to remedial efforts. It is believed that the current sewer ordinance contains adequate language to enforce the removal of inflow connections. Though Ill elimination is expected to be cost effective for the City, the cost and inconvenience to residents in the Pismo Heights could also be considered as a factor. The estimated cost savings indicated in Table 5-3 are less than 5% of the cost of the proposed downstream collection system improvements. If initial remedial efforts appear to impact residents of the Pismo Heights to an unacceptable level, the City has the flexibility to pump and treat the Ill -related flows by providing additional capacity in downstream facilities. 5-7 Collection WASTEWATER COL 6.1 EXISTING COLLECTION FACILITIES ,n Master Plan - Chapter 6 N SYSTEM ANALYSIS The Pismo Beach wastewater collection system consists of approximately 35 miles of gravity sewer pipe and 9 wastewater lift stations. Table 6-1 provides an inventory of the current system pipeline infrastructure, and Figures 6-1, 6-2, and 6-3 display the existing system. Table 6-2 summarizes the characteristics of the 9 existing wastewater lift stations. Table 6-1 Sewer Collection System Inventory Pipe Diameter Approximate Length of Gravity Sewers Approximate Length of Force Mains (feet) (miles) (feet) (miles) 6 60,500 11.5 3,800. 0.7 8 95,300 18.0 7,800 1.5 10 11,200 2.1 6,800 1.3 12 10,600 2.0 2,600 0.5 15 3,600 1 0.7 -- -- 16 -- -- 2,600 0.5 Approx. No. of Sewer Manholes 450 -- 6.2 COLLECTION SYSTEM MODELING In order to evaluate the performance of the existing and future collection systems, two hydraulic models were developed for the analysis. One model was developed for the gravity collection system using the Hydra 6 program. This powerful program is widely used in the wastewater industry because of its ability to analyze the system as a hydraulic unit. The following design criteria were applied to the existing and future collection systems: Gravity pipes should flow no more than 70% full under build out conditions. A minimum pipeline velocity of 2.0 feet per second should be maintained. A maximum pipeline velocity of 10.0 feet per second should not be exceeded. Existing and future system deficiencies are noted in Section 3.0 below. Selected computer model results are included in Technical Appendix B (separate volume). A second computer model was developed for the lift stations and force mains. This model and the related design criteria are described in Section 5.0. 6-1 -r r PRIVAT LIFT ST1 dip CITY OF 0-1� PISMO BEACH 77 �E[,ONA j 9 Am zzi AfAlllf RLZgp SUNSET PALISAEMS LIFT STATION P.9C6Tc Ocean MA TnE RDAD w __-.:�� �• - N LANE � I',QI� r -- .•' PRICE STRFE T •�� ±..tee •�' I �'�•�i. �rll Sanitary Sewer Line Size 4" Line - — 6" Line !J 8" Line 10" L1ne 12" Line _11JUll' _ _.... i 5" line 18" line - V FORCE MAIN Figure 6-1 Egistin Facilities S� loaf-aC-k1 0 ZOC 400 Boo John L. Wallace & Associates &-'22 F r r J PacEc ocean Ott FA U_S- —MAO Q= Oqm�ft~�W� � PISMO BEACH Wastewater Master Plan Figure 6-3 Existing Facilities Downtown Area Sanitary Sewer Line Size - 6" L1ne 8" Lane 100 Line 12' Line 15" Line 18" Line — — — — FORCE MAIN 50y 125 251 500, � d/ John L. Wallace & Associates a-5 6.3 GRAVITY SYSTEM ANALYSIS AND DEFICIENCIES Based on the computer model developed for the gravity system, a number of system deficiencies were noted. This section describes system deficiencies, identifies improvement strategies and alternatives, and provides a budget cost estimate to complete the improvements. In Chapter 8, the recommended improvements will be summarized in a prioritized capital improvement program. Shell Beach Interceptor Line A dedicated gravity main was constructed from the Shell Beach area to the Addie Street lift station in 1973. The Shell Beach Interceptor varies in diameter from 12" in flat sections to 8" in steeper reaches, The full flow capacity of much of the interceptor is approximately 900 gpm. However, when all upstream lift stations are pumping, the line must convey a peak flow of 1,300 gpm. Given the minimal flow currently reaching the Freeway Foothills Station, concurrent pumping under current conditions is unlikely. However, metered data on the interceptor shows that flows often reach 700 gpm during the morning peak hour. In addition, as development continues tributary to Freeway Foothills, the line is expected to surcharge under peak conditions. Two alternatives were considered for addressing the capacity issues in the interceptor as follows: Gravity Alternative No. 1: Replace the existing 12" gravity interceptor from its origin in Shell Beach to the Addie Street lift station. An 18" gravity line will be required at an estimated cost of $100 per foot. Force Main Alternative No. 2: Construct a new 12" force main to divert flows from the Sunset Palisades, Vista Del Mar, Spyglass, and private lift stations directly to the WWTF. A preliminary alignment for the proposed force main is shown in Figures 6-4 and 6-5. The unit cost for the new pipe is estimated at $50 per foot, and the total length of 15,000 feet (2.84 miles) is slightly less than Alternative No. 1. In addition to these direct cost savings, Table 6-3 summarizes the additional cost benefits that will be realized with the force main alternative. Capital. Improvement Priorities Are Listed By Text Color Priority 1: RED Priority 2: GREEN Priority 3: BWE �n FORM'7 IN 21-11 I -- r Pacrfic Ocean STANDBY GENERAIOR 0 l d I000, d UA I Q U 0. 1 VISTA DEL U r rvr+ OF" APMd M� 110, ---- 49d OM w- W-- - CITY OF PISMO BEACH CE 'ATION City MA ME Rpgp 8" LOBtJRtL LAN£ y ` o 1110� E \ 10' M ------------ PRICE S CAPITAL IMPROVEMENTS PLAN Figure G-4 1" = 801y 0 200 400 Boo John L. 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Approx. Replace existing sag with 8" Pismo Beach pier length = 650' pipeline - maintain adequate fall. Ocean Blvd. upstream of Capacity of existing 8" line is Replace existing pipe with a Vista Del Mar lift station inadequate for build -out minimum 10" sewer line. conditions. Length = 1,100 ft. 6.4 LIFT STATION ANALYSIS AND DEFICIENCIES A second computer model was developed for the lift stations and force mains in the City collection system. As shown in Figure 6-1, City lift stations often pump into common force mains with other stations. As a result, the pressure conditions at each station change depending on the number of pumps operating in a given moment. New public and private stations have been added in the Shell Beach area without the benefit of such a computer model. The resulting increased pressure at the Sunset Palisades lift station has contributed to frequent pump failures. An upgrade of this station is under construction, and therefore all information pertaining to the Sunset Palisades L.S. assumes the upgrades have been completed. As part of the Master Plan, each lift station was analyzed and deficiencies were noted. Design criteria that apply to the lift stations and force mains are summarized below: • Force main velocities should be greater that 2.0 feet per second to maintain self cleaning properties but less than 5.0 feet per second to minimize energy losses. • Force mains should have adequate capacity to convey peak flows with all City lift stations operating concurrently. • Lift stations should be able to convey peak flows with the largest pump out of service. Station "capacity" is therefore calculated with the largest pump out of service. • Lift station wet wells should be sized to limit the number of pump starts per hour to acceptable limits as defined by the pump manufacturer. • Lift stations should have a means of conveying peak flows during a power outage. This will typically be a stand by generator. In assembling the following cost estimates, it is assumed that the generator will include sound attenuation equipment and will be installed above ground. The additional cost to install a lift station generator below ground to minimize noise and visual impacts is estimated at $200,000. Alternatively, the City could initially purchase a mobile generator for any given lift station, with the intent of permanently installing the unit either above or below ground after the issue of noise and visual impacts is addressed. • The City owns a portable stand by pumping station that can be used to bypass a lift station in an emergency. In the future, this pump can be used at all stations with the exception of the Sunset Palisades L.S., where the discharge pressure is too high. Each station should have an emergency connection available for a bypass operation. Each lift station and related force main is analyzed in the following section. 6-11 ADDIE STREET LIFT STATION � After completion of the proposed force main realignment project, the Addie Street lift station will serve the Pismo Heights, the Motel District, the Downtown Commercial Core, and the Freeway Foothills planning areas. The station currently serves the entire Shell Beach area as well. The Addie Street L.S. is both the oldest and the largest pump station in the City. In addition, it has been one of the main sources of spills and other capacity -related problems. The current peak hour flow to the station is estimated at approximately 3,300 gpm. The station rl and the gravity collection system upstream are inadequate to handle this peak condition. The critical element of pump redundancy is also lacking. Even during the dry season, the station periodically requires the use of all three pumps. If one pump fails during such a condition, the wet well would surcharge the shallow upstream gravity system as quickly as five minutes after station alarms indicate a high water condition. Portions of the electrical system at the Addie Street L.S., including the stand by generator, date back to the original installation in 1953. The equipment is beyond its useful service life and warrants replacement. According to operations staff, some older components are no longer supported by manufacturers. If these systems fail, the components will have to be T completely replaced, resulting in unacceptable downtime in a station without redundancy. UJ The influent entering the existing wet well first passes through two channel -type wastewater 1 grinders. The resulting turbulence contributes to the release of dissolved hydrogen sulfide and causes an on -going odor issue at the station. Operations staff have used various odor inhibiting chemicals with some success, but the problem has persisted. It is recommended that the proposed station eliminate the use of grinders and utilize non -clog pumping technology similar to other City stations. Appropriate solids handling equipment should then be incorporated into the proposed headworks at the WWTP. In the first quarter of 1999, the City completed two projects to decrease the peals flows at Addie Street and add emergency redundancy as follows: 1) The City constructed an emergency bypass connection for use with the trailer mounted stand by pump. The pump can discharge up to 2,000 gpm (2.9 mgd). 2) Historically, wastewater discharged from the Five Cities lift station flowed to Addie Street with a peak flow of 600 gpm. This force main has been rerouted R directly to the WWTP, thereby providing a 20% reduction in peak flow. These projects were constructed as effective temporary measures, but they do not mitigate the need for permanent improvements at the Addie Street lift station. Improvement Alternatives ,_1 Improvement alternatives can be described in two basic categories: 1) construct improvements to the existing station or 2) construct a new lift station. Adequate improvements to the existing lift station are not expected to be feasible or cost effective for the following reasons: 6-12 • The wet well for the station needs to be expanded and lowered in elevation to accommodate gravity system improvements upstream and allow for adequate emergency response time. A difficult interim bypass would be necessary, and effective reuse of portions of the existing concrete structure would be costly. • The station mechanical and electrical systems would require complete replacement, furthering the duration of a costly bypass system. There are few elements in the existing station that would be re -used in an upgraded system. • The cost to clean, prepare, and rehabilitate corroded elements of the station would be excessive when compared to corrosion control measures for a new structure. For these reasons, a new lift station constructed adjacent to the existing facility is recommended. A new pump station utilizing submersible pumps is recommended as the most cost effective and functional solution for the City. The following table summarizes the features of the new station: Table 6-5 Addie Street Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Three 1,020 dry pit non -clog Three 1,500 gpm submersible capacity pumps - 15 HP motors pumps to redundantly meet future peak of 2,800 gpm Wet well capacity Inadequate response time, The wet well should allow no excessive turbulence, and more than 10 starts per hour odors. with a normal operating volume of 4,500 gallons. Turbulence should be minimized. Stand by power Stand by generator beyond its Add new permanent stand by useful service life generator system. Emergency bypass Bypass Available Maintain bypass capability Corrosion and odor Hydrogen sulfide release Coat and protect all new produces odor and corrosion concrete. Consider using an engineered odor control system. Other components Construct an attractive new pump building with yard fencing and landscape screening. All sound -producing equipment should include silencing features in order to meet General Plan requirements for noise generation. Estimated budget cost of $800,O00 proposed improvements (see cost breakdown in Tech. App. C) 6-13 I f FIVE CITIES LIFT STATION The Five Cities lift station serves the Pismo Creek and Pismo Marsh planning areas. Operations staff have reported existing capacity problems with the station under peak conditions - an assessment supported by the peak flow calculations. The basic station functions acceptably under normal operating conditions, but lacks adequate peak capacity and stand-by power. The existing 6" force main that connects the Five Cities Lift Station to the 16" force main from Addie Street is undersized for peak flows and has experienced some age - related problems. The force main should be replaced with an 8" pipeline. The proposed improvements to the station are summarized in Table 6-6 below. Table 6-6 Five Cities Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Two 400 gpm self -priming Increase capacity to 625 gpm capacity pumps - 25 HP motors with new 30 HP motors and force main upgrade. The existing pumps are adequate. Wet well capacity At 10 starts/hour, the existing Due to space constraints, a wet well will only support a larger wet well may not be pump flow rate of 280 gpm. feasible. Add VFD's to the system. Stand by power Existing manual transfer switch Add permanent stand by system generator. Emergency bypass None available Add bypass capability Corrosion and odor No problems reported Not applicable Other components Existing structure will not Construct new pump house house generator and is for system. deteriorating. Existing 6" force main is Construct new 8" force main undersized for build -out. (2,300 feet) Estimated budget cost of Station Improvements = $175,000 proposed improvements Force Main Upgrade = $135,000 Altematives to the Not applicable proposed improvements 6-14 I' P/SM0 OAKS LIFT STATION The Pismo Oaks lift station serves the Oak Paris Heights planning zone and is tributary to the l� Los Robles Del Mar Specific Plan area. With a capacity of 550 gpm, the existing submersible pumps at the Pismo Oaks L.S. adequately convey the existing peak hourly flow of 330 gpm. In T addition, it appears that the station was originally sized to serve the build out of the Oak Park Heights planning area, which is expected to generate a future peak flow of approximately 570 gpm. However, once the Los Robles Del Mar project is completed, an additional 200 gpm will flow to the station for a total peak flow of 770 gpm (see Pg. 6-10). In addition to capacity issues, portions of the existing station infrastructure are inadequate and/or corroded. Table 6-7 below summarizes the station deficiencies and recommended improvements. Table 6-7 Pismo Oaks Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Two 550 gpm submersible Two 770 gpm submersible capacity pumps - 20 HP motors pumps - 30 HP motors. Wet well capacity Requires 825 gallons for 10 Future pumps require 1,155 starts per hour. Existing wet gallons for 10 starts per hour. well provides 529 gallons. Add VFD drives to avoid wet well replacement. Stand by power Manual transfer switch and Add Permanent stand by receptacle for connection to power. mobile generator. Emergency bypass No connection available. Add connection for mobile pump. The wet well must be flooded to 2't above the existing high water alarm. Corrosion and Odor The unprotected wet well is Coat the existing wet well with severely corroded. an H2S resistant material. Eliminate vertical fall in higher influent pipes. Other components Station needs slide rails, misc. Incorporate improvements into control components, and new station upgrade. valving. Estimated budget cost of $300,000 proposed Improvements Alternatives to the If the Los Robles Del Mar project is required to connect proposed improvements downstream of the station, the estimated cost would be reduced by $60,000. The City could also purchase a mobile generator as a separate project, reducing the cost by approx. $35,000. 6-15 r� FREEWAY FOOTHILLS LIFT STATION The Freeway Foothills lift station serves the areas within the Mattie Road annexation zone. It appears that the station was designed for build out of the area, given that the calculated peak flow of 272 gpm is closely matched to the station capacity of 275 gpm. This submersible station functions acceptably but lacks stand-by power. An adjacent commercial development is currently in progress that will reduce the available equipment and access area of the station to minimum levels. It is recommended that the City maintain a minimum equipment area of 20' x 20' with adequate access for the City's pumping/cleaning vehicle and stand by pump. The proposed improvements to the station are summarized in Table 6-8 below. Table 6-8 Freeway Foothills Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Two 275 gpm submersible No change - pumps adequate capacity pumps - 20 HP motors for build out Wet well capacity The level set points in the wet No change well can be modified slightly to achieve the required volume of 413 gallons for 10 starts/hour Stand by power None - no receptacle or Add manual transfer system manual transfer switch immediately and purchase mobile generator. Station generator permanently in the future. Emergency bypass None available Add bypass capability Corrosion and odor Existing slide rails and related Replace with stainless steel. hardware are galvanized steel and are corroded Other components Not applicable Not applicable Estimated budget cost of Stand by power system (incl. mobile generator) = $65,000 proposed improvements Remainder of proposed items = $15,000 Alternatives to the Not applicable proposed improvements 6-16 J VISTA DEL MAR LIFT STATION The Vista Del Mar lift station serves the Shell Beach planning area. The station was upgraded in 1995 in a project that included a new dry pit system and stand by generator. The service zone is approximately 90% built out, and the estimated average daily flow to the station is 211,800 gal/day (147 gpm). The current station capacity is 385 gpm, which will accommodate a peaking factor of approximately 2.6. A more typical peak hour factor for communities the size of Shell Beach is 4.0, and a station capacity of approximately 680 gpm is required to accommodate this peaking factor. The previous Wastewater System Master Plan (PRC Toups, 1982) recommended a capacity of 770 gpm for the station. After the upgraded station was placed into service, the new Essco pumps began to exhibit cavitation problems. Cavitation results when the pressure at the inlet of a pump drops below the vapor pressure of the liquid and can damage the pump. The problem was mitigated by injecting air into the pump system, but this system uses small diameter piping that frequently clogs. In addition, operations staff have reported that the pumps routinely air lock. Two f factors could be contributing to the cavitation problem as follows: The existing 4" suction lines exceed recommended velocities at design flow. The suction losses created by such high velocities can lead to cavitation. Based on the manufacturer's information, the Essco pumps have a `flat" pump curve, j which means that small changes in pressure result in large changes in flow. For this reason, when other lift stations in the system are off, the Vista Del Mar pumps could be discharging significantly more than the design flow. This condition would further increase the velocity in the small suction pipes. It should be noted that City operations staff have not expressed capacity -related problems at the station. It is conceivable that water use patterns in the Shell Beach area reflect a lower peaking factor. At the bottom of Table 6-9, an alternative project is identified that would allow the City to correct station deficiencies without replacing the existing pumps. Operations staff 1 could then closely monitor station operation under peak conditions to ensure the station does not activate both pumps to keep up with incoming flows. 6-17 Table 6-9 Vista Del Mar Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Two 385 gpm non -clog pumps Two 680 gpm non -clog pumps capacity 60 HP motors 75 HP motors Wet well capacity Requires 578 gallons for 10 Proposed pumps require starts per hour. Existing wet 1,020 gallons of storage. Plan well provides 141 gallons. area of new wet well = ±90 fe Stand by power Existing generator on site Utilize higher efficiency pumps and soft start controls to maintain generator use. Emergency bypass None available Add bypass capability Corrosion and odor Existing wet well is coated Coat proposed wet well Other components 4" suction lines are undersized Add 8" suction lines. Estimated budget cost of $166,000 proposed improvements Altematives to the Maintain existing pumps and closely monitor peak flows. proposed improvements Operations staff have not reported any capacity -related problems, possible due to low per unit occupancy. Construct new wet well (8`-diam) and replace 4" suction lines with new 8" pipes. Alternative project cost = $64,000 G-18 j/ SPYGLASS LIFT STATION The Spyglass lift station serves the Spyglass, St. Andrews, and Spindrift planning areas. The station is approximately 26 years old but is currently sized adequately for build -out. The station wet well is undersized, and the system does not have permanent stand by power. The proposed improvements to the station are summarized in Table 6-10 below. Table 6-10 Spyglass Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Two 385 gpm dry pit non -clog No capital improvement capacity pumps - 25 HP motors proposed - replace pumps and motors at end of service life. Wet well capacity The existing wet well will allow Purchase high quality motors up to 15 starts per hour, which that can intermittently perform is unacceptable for most at 12 to 15 starts per hour. motors. Maintain pump alternation. Stand by power Existing manual transfer switch Add permanent stand by system generator system. Emergency bypass Available -- Corrosion and odor No problems reported Not applicable Other components Existing electrical starters and Move starters and other other -critical components are components to above -ground in a deep dry well next to the enclosure. pumps. Estimated budget cost of Station Improvements = $110,000 proposed improvements Alternatives to the Eliminate the electrical upgrades described in "Other proposed improvements components" at a cost savings of $30,000. 6-19 PG&E LIFT STATION The PG&E lift station serves a small area within the Pismo Heights and Industrial planning zones. Due in part to small flows, the station functions adequately during peak conditions. Operations staff periodically replace pumps and perform other maintenance functions on the station. A small stand by power supply is recommended for the station, along with bypass capabilities. The proposed improvements to the station are summarized in Table 6-11 below. Table 6-11 PG&E Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Two dry pit non clog pumps No capital improvement capacity 3 HP motors proposed - replace pumps and motors at end of service life. Wet well capacity The existing wet well capacity No improvements proposed is inadequate for the pump capacity, but pump cycling problems are not anticipated due to minor flows. Stand by power Existing manual transfer switch Add permanent stand by system generator system. Emergency bypass None available Add bypass capability Corrosion and odor No problems reported Not applicable Other components Not applicable Not applicable Estimated budget cost of Station Improvements = $24,000 proposed improvements Alternatives to the Not applicable proposed improvements 6-20 c,l SAINT ANDREWS LIFT STATION The Saint Andrews lift station serves a small residential area in the Saint Andrews planning zone. Similar to the PG&E L.S., the station handles minor flows. A small stand by power supply is recommended for the station, along with the addition of bypass capabilities and electrical upgrades. The proposed improvements to the station are summarized in Table 6-12 below. Table 6-12 Saint Andrews Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Two submersible pumps No capital improvement capacity 2 HP motors proposed - replace pumps and motors at end of service life. Wet well capacity The existing wet well capacity No improvements proposed is inadequate for the pump capacity, but pump cycling problems are not anticipated due to minor flows. Stand by power Existing manual transfer switch Add permanent stand by system generator system. Emergency bypass None available Add bypass capability Corrosion and odor No problems reported Not applicable Other components The existing electrical panel is Provide electrical system at the end of its useful service upgrades as necessary. life. Estimated budget cost of Station Improvements = $50,000 proposed improvements Alternatives to the Not applicable proposed improvements 6-21 SUNSET PALISADES LIFT STATION The Sunset Palisades lift station serves residential neighborhoods within the Ontario Ridge, Sunset Palisades, and South Palisades planning areas. As of June, 1999, the lift station is being upgraded to address capacity and reliability problems. Though stand by power should eventually be added to the station, the dual wet wells and gravity system provide a long response time of approximately 4 hours before residents are impacted. The proposed improvements to the station are summarized in Table 6-13 below. Table 6-13 Sunset Palisades Lift Station Summary Station Component Existing Lift Station Proposed Lift Station Pump design and Two dry pit non clog pumps No improvements proposed capacity 60 HP motors with VFD's Wet well capacity The VFD's minimize pump No improvements proposed cycling and use of wet well volume Stand by power Existing manual transfer switch Add permanent stand by system generator system. Emergency bypass Bypass available No improvements proposed Corrosion and odor No problems reported No improvements proposed Other components Not applicable No improvements proposed Estimated 'budget cost of Stand by Power Improvements = $65,000 proposed improvements Alternatives to the Not applicable proposed improvements Consolidation of Sewer Lift Stations The feasibility of combining localized lift stations into larger regional stations was examined as part of the Master Plan. After an initial analysis, it was determined that the only location where consolidation might be feasible is in the Shell Beach area. The Vista Del Mar fift station is significantly lower in elevation than both the St. Andrews and Spyglass lift stations. However, in order to eliminate St. Andrews and Spyglass, an excessively -deep gravity sewer (over 30' deep) would be necessary. Since the costs associated with the proposed improvements at Spyglass and St. Andrews are relatively small in relation to reconstructing the gravity sewer in the area, it was determined that lift station consolidation was not feasible. The addition of future lift stations associated with new development should be avoided where possible. 6-22 6.5 ODOR AND CORROSION CONTROL In the absence of adequate oxygen, bacteria living in municipal wastewater begin to convert sulfate, a common constituent in wastewater, into a dissolved compound know as hydrogen sulfide (112S). This compound subsequently escapes the wastewater, particulary in areas of high turbulence, and enters the air environment as a gas. Once the gas is present in a gravity collection system, it can escape through man -hole covers, roof vents, and lift stations, causing an offensive rotten -egg odor in areas of release. At higher concentrations, the gas can cause eye irritation, respiratory problems, and even death. In addition to its odorous properties, the �. gas can form sulfuric acid in the presence of air. This acid will corrode concrete and other materials often found in wastewater collection systems. Typically, oxygen levels in gravity wastewater systems remain adequately high to prevent the formation of excessive hydrogen sulfide. However, the gas forms readily in the following common components of a collection system: Lift station wet wells where wastewater can be stored for more than 30 minutes during low flows. Long wastewater force mains where the absence of an air -water interface contributes to anaerobic conditions. Areas within a gravity collection system where solids have deposited due to inadequate velocities or lack of cleaning. �f The following section summarizes the system components that experience on -going H2S- related problems. Shell Beach Interceptor and Addie Street L.S. Five public and two private lift stations discharge directly into the Shell Beach Interceptor from a network of force mains. The most remote station is approximately 2 miles from the discharge point. Hydrogen sulfide forms in the long force main and is discharged to the interceptor. Field inspection of sewer manholes along the interceptor have revealed extensive corrosion in the system. Fortunately, the interceptor remains isolated from the remainder of the downtown µ' gravity system and discharges directly into the Addie Street wet well. Once the sulfide -laden wastewater reaches Addie Street, turbulence at the existing sewage grinders contributes to the release of hydrogen sulfide and causes odor problems. The proposed Shell Beach force main relocation problem will substantially reduce hydrogen sulfide levels in the interceptor and at Addie Street. However, due to the structural damage that has already occurred in the existing manholes along the interceptor, each manhole should be rehabilitated with a sulfide -resistant coating system. The budget cost to rehabilitate each of the 40 manholes is estimated at $140,000. 6-23 Pismo Oaks Lift Station Severe corrosion of the existing concrete wet well is evident at the Pismo Oaks lift station. The gravity areas upstream of the station do not have a history of hydrogen sulfide corrosion. However, when wastewater enters the station it drops several feet before reaching the normal water level. This turbulence will cause dissolved H2S to escape. In addition, if the wet well sits stagnant for a period of time, H2S that subsequently forms in the wet well could be release when new influent cascades into the station. As addressed previously in Table 6-7, the vertical drop should be eliminated when the station is rehabilitated. Methods of Hydrogen Sulfide Control l A number of methods exist to control or limit the formation of hydrogen sulfide in a sewer collection system. In general, these methods involve the injection of a chemical to inhibit the formation of the gas from sulfate in the wastewater. Chemicals employed in the industry include ferrous sulfate and other metal salts, hydrogen peroxide, nitrate, and base solutions. Air injection has also been employed in long force mains to prevent the anaerobic conditions that cause H2S formation. The City currently uses ferric chloride, an iron salt, to minimize H2S formation. This chemical has proved effective in similar applications where injection rates were optimized for the application. In order to minimize odor at the treatment plant, it is recommended that the City maintain its existing H2S-limiting practices even after the Shell t Beach force main system is relocated. In addition, the existing force mains should be flushed periodically with a strong base to eliminate the biological slime layer that typically forms in force mains. «E r Wastewater Collection WASTEWA Master Plan - Chapter 7 LLECTION SYSTEM OPERATION 7.1 COLLECTION SYSTEM MAINTENANCE The long term operations plan of the City Wastewater Department is to perform preventative and pro -active system maintenance in order to prevent avoidable failures. It is also the intent of operations staff to complete most small capital improvement projects with in-house staff. However, due to the age and condition of City facilities, operations personnel are compelled to focus on immediate system needs. The following table summarizes collection system operations tasks, including an estimation of weekly man hours: Table 7-1 Estimated Collection System Maintenance Requirements Task Description Current weekly man- hours available Recommend weekly man hours Sewer line cleaning and maintenance 32 60 to 80 Lift station checks and maintenance 16 20 Improvement protects minimal 20 Pre-treatment compliance, Ill monitoring, regulatory compliance minimal 15 Public service response 10 (Varies) 10 (Varies) TOTAL ESTIMATED WEEKLY MAN HOURS 120 to 145 The sewer cleaning man-hours referenced should accommodate the RWQCB requirements for the cleaning of system "hot -spots," in addition to allowing the City to clean all gravity lines every 2 years as required by the revised RWQCB discharge permit. The estimated man-hours include an allowance for vacation time, sick time, and related benefits. 7.2 STAFFING LEVELS Given the results of Table 7-1 above, it is recommended that the City maintain 3 to 4 wastewater collection system operators. This .recommendation should be coordinated with the recommended treatment facility staff referenced in the treatment portion of the Master Plan. 7-1 Wastewater Collection System Master Plan - Chapter 8 REr.- 1� MENI ATIONS ANIP CAPITAL IMPRQVF;MEtK3'TS ` 8.1 RECOMMENDATIONS The results of this study are presented in this chapter as the recommended Wastewater �} Collection System Master Plan for the City of Pismo Beach. The Master Plan consists of 4Y staged improvements to correct existing deficiencies and provide for future system expansion. Cost estimates were prepared for each project and used to develop a capital improvement program. The previous chapters provide discussion which results in various recommendations. The recommendations are shown in Figures 6-4 and 6-5 and are summarized below: Due to capacity issues in the existing Shell Beach interceptor, construct a 12" force main from Shell Beach to the Addie Street force main. 2. Replace the Addie Street lift station with a new facility that meets applicable requirements for capacity and redundancy. 3. Provide improvements to other lift stations as summarized in Chapter 6. 4. Upgrade the downtown collection system upstream of Addie Street by constructing a new 18" replacement interceptor and diverting selected flows to the interceptor. 5. Provide other gravity system improvements as summarized in Chapter 6. 6. Eliminate infiltration/inflow in the Pismo Heights area by removing illegal storm drain connections and sealing flood -prone manhole covers. If necessary, individual residents should be contacted for on -site inspections. 7. Continue the existing ferric chloride injection practices to reduce the production of hydrogen sulfide gas. Coat approximately 40 manholes on the existing interceptor line with a hydrogen -sulfide resistant coating. 8. Maintain a collection system staff of a minimum of three persons in order to provide for adequate cleaning practices, lift station checks, and other preventative measures. 8.2 CAPITAL IMPROVEMENT PROGRAM The following section summarizes a three -priority capital improvement program reflecting the relative importance and timing of the projects. The three priorities are described as follows: • Priority 1 improvements provide upgrades to currently inadequate facilities and should be constructed in the next 5 years. J Priority 2 improvements correct less -critical existing deficiencies and provide for build out of the City. Stage 2 projects should be completed in the next 5 to 10 years. Priority 3 improvements generally reflect localized inadequacies of a non -critical nature and should be completed in the next 10 to 15 years. 8-1 �! Budget cost estimates have been prepared for the proposed improvements. A preliminary cost breakdown for each project is included in Technical Appendix C. All estimates are based on 1999 costs, with an Engineering News Record (ENR) Construction Cost Index (CCI) of 7000. The projects listed in the following tables are arranged in order of descending priority. An implementation schedule for the Priority 1 projects is shown in Figure 8-1. Table 8-1 Priority 1 Capital Improvements Budget Cost No. Project Name Description Estimate 1-1 Shell Beach force main Bypass the existing interceptor with a See Note 1 relocation new 12" force main to the Addie Below Street L.S. force main. 1-2 Pismo Heights Ill Reduce Ill in the Pismo Heights area $50,000 Elimination by contacting residents and repairing leaks. 1-3 Addie Street lift station Construct a new submersible lift $800,000 replacement station facility at Addie Street 1-4 Pismo Oaks lift station Upgrade the Pismo Oaks L.S. to $300,000 upgrade correct structural, capacity, and operational problems 1-5 Interceptor manhole Coat interceptor manholes with a $140,000 rehabilitation sulfide -resistant product 1-6 Five Cities lift station Upgrade the Five Cities L.S. with new $310,000 upgrade pumps and stand by power. Replace the existing 6" force main with an 8". 1-7 Park/Cypress replacement Combine the three existing lines into $355,000 interceptor one 18" replacement interceptor with additional depth. Divert flows as summarized in Chapter 6. TOTAL OF PRIORITY 1 IMPROVEMENTS (CCI = 7000) $1,955,000 Notes: 1. As a result of the draft Master Plan report published in June, 1999, the Shell Beach force main relocation project was funded for the 99/00 fiscal year in the amount of $1,120,000 and therefore does not appear in the table. 8-2 Table 8-2 Priority 2 Capital Improvements Budget Cost No. Project Name Description Estimate 2-1 Vista Del Mar lift station Upgrade the Vista Del Mar L.S. to $166,000 upgrade correct capacity & operational issues 2-2 Freeway Foothills lift Upgrade the Foothill Freeway lift $80,000 station upgrade station to correct operational problems and add stand by power. 2-3 St. Andrews lift station Add stand by power and upgrade $50,000 stand by generator & electrical system electrical upgrades TOTAL OF PRIORITY 2 IMPROVEMENTS (CCI = 7000) $296,000 Table 8-3 Priority 3 Capital Improvements Budget Cost No. Project Name Description Estimate 3-1 Sewer sag repair adjacent Correct existing sag with new 8" $62,000 to Pismo Pier sewer. 3-2 Spyglass lift station Upgrade the Spyglass lift station to $110,000 upgrade add stand by power and correct operational deficiencies 3-3 PG&E lift station stand by Add stand by power $24,000 generator 3-4 Sunset Palisades lift Add stand by power See Note 1 station stand by generator Below 3-5 Vista Del Mar gravity Replace existing 8" sewer with a 10" $114,000 system upgrade sewer to prevent system surcharging 3-6 Pismo Oaks gravity Replace the existing 10" sewer with a $300,000 system upgrade 12" sewer to meet future capacity requirements TOTAL OF PRIORITY 3 IMPROVEMENTS (CCI = 7000) $610,000 TOTAL OF ALL IMPROVEMENTS (PRIORITY 1, 2 & 3) $2,861,000 Note: 1. As a result of the draft Master Plan report published in June, 1999, a dedicated mobile generator was funded for the 99100 fiscal year and therefore a cost for this item does not appear in the table. 8-3 L L N r N CL g .. 00 r E y U EA r wook E 0 �d = a ILL ii S N ISM ' A � :N :v :E C r a N :d r N oLq r— a r -- ._.._.......-. ........ ...�.-. .. ..��.��. �. ... .�... ..�..... wn�..�......... .... . .Z r 2.r V. rIL ;N r G O r r i i I is c iC is im :y im iv Ci Ws O2 WO mc :2° ° C ir ' E;•g O i m iv r t� ° c :'im �m d U :d U W- ........... CL ............. f ............. ......... .. O R41 ........... ........................ ............. I ............. 10 004 C4 ............. ............. ............ ..... ..... ........... .................. do rL Ev do IL P,.... ......... ...... ...... ............ ---- - ----- - I ---- ----- -- ............ ............................ ........... ............. ............. ........... c C r 'A 0) 0 r CL E cc TECHNICAL APPENDIX C Budget Cost Estimates Capital Improvements Description Priority 1 Shell Beach Force Main Relocation Addie Street Lift Station Replacement Pismo Oaks Lift Station Upgrade Interceptor Manhole Rehabilitation Five Cities Lift Station Upgrade Park/Cypress Gravity Sewer Improvements Priority 2 Vista Del Mar Lift Station and Force Main Upgrade Freeway Foothills Lift Station Upgrade St. Andrews Lift Station Stand By Power and Electrical Upgrade Priority 3 Sewer Sag Repair Adjacent to Pismo Pier Spyglass Lift Station Upgrade Pacific Gas and Electric Lift Station Stand by Generator Sunset Palisades Lift Station Stand By Generator Vista Del Mar Gravity System Upgrade Pismo Oaks Gravity System Upgrade Pane 1-3 1 1 2 3 3 4-5 4 4 5 6-7 6 6 6 7 7 7 Shell Beach Force Main Relocation Shell Beach Force Main Relocation Quantity Unit Unit Price Total Pr 10 PVC pipeline 15000 If $50 $750 and Appurtenances 1 Is $20,000 $20 W.-- 1Is $30,000 $30 Construction Subtotal Budget Contingency (20%) $160,000 Engineering & Planning (15%) $120,000 Contract Administration (5%) $40,000 Addie Street Lift Station Replacement Addie Street Lift Station Replacement Pumping Equipment 1 $50,000 $50, Wet well structure (18' x 8' x 15' deep) 1 $85,000 $85, Yard and interior pipinglvaiving 1 $50,000 $50, Mechanical systems 1 $25,000 $25, Lift station facilities building 1 $100,000 $100, Site Work 1 $30,000 $30, Station electrical and control system 1 $100,000 $100, Budget Contingency (20%) Parktoypress Gravity Sewer improvements ir'nntraclt Administration (5%) Page 1 of 7 $110 $110 $28 Pismo Oaks Lift Station Upgrade Pismo Oaks Lift Station Upgrade New pumps & base elbows 1 LS $40,UUU ;�qu,uuu VFD controls 1 $30,000 $30,000 Stand by generator 1 $40,000 $40,000 Emergency connection 1 $8,000 $9,000 Wet well coating 1 $35,000 $35,000 Slide rails/ valvinglpiping 1 $20,000 $20,000 Misc. electrical/controls 1 $15,000 $15,000 Construction bypass 1 $25,000 $25,000 Construction subtotal $214,000 20% Construction Contingency $43,000 15% Engineering and Planning $32,000 Contract Administration (5%) $11,000 Interceptor Manhole Rehabilitation Interceptor Manhole Rehabilitation item Quantity Unit Unit Price Total Price existing sewer manhole 40 ea $2,000 $80,000 Bypass operations (if necessary) 1 Is $20,000 $20,000 Construction Subtotal $100,000 Budget Contingency (20%) $20,000 Engineering & Planning (15%) $15,000 Contract Administration (5%) $5,000 Page 2 of 7 Five Cities Lift Station Upgrade Five Cities Lift Station Upgrade Item Quantity Unit Unit Price Total Price New motors (30 HP) 1 $8,000 $8,000 VFD's and related electrical 1 $38,000 $38,000 System bypass 1 $7,000 $7,000 Stand by power system 1 $48,000 $48,000 New enclosure 1 $20,000 $20,000 Construction Subtotal $121,000 Budget Contingency (20%) $24,000 Engineering & Planning (15%) $18,000 Contract Administration (5%) $6,000 TOTAL PROJECT BUDGET #169,000 Five Cities Lift Station - Force Main Upgrade Item Q;,rtiiity Unit Unit Price Total Price New Force Main 2300 LF $35 $80,500 Bridge Crossing 1 $10,000 $10,000 Connections/Valving 1 $10,000 $10,000 Construction Subtotal $100,600 Budget Contingency (20%) $20,000 Engineering & Planning (15%) $15,000 Contract Administration (5%) $5,000 TOTAL PR0 -ECT BUDGET $140,600 TOTAL BUDGET FIVE CITIES UPGRADES #309,500 Park/Cypress' Gravity Sewer Improvements Park/Cypress Gravity Sewer Improvements Item Quantity Unit Unit Price Total Price 21" gravity sewer 1300 If $100 $130,00D Sewer Laterals 25 ea $1,700 $42,500 Sewer Manholes 6 ea $3,500 $21,000 Connections 1Is $10,000 $10,000 Flow Diversion (two locations) 1 Is $30,000 $30,000 Demolition i is $20,000 $20,000 Construction Subtotal $253,500 Budget Contingency (20%) $51,000 Engineering & Planning (15%) $38,000 Contract Administration (5%) $;13,+_,^^l TOTAL PROJECT BUDGET $355,500 Page 3 of 7 � N Vista Del Mar Lift Station Upgrade Vista Del Mar Lift Station - Base Option Item Quantity Unit Unit Price Total Price New Pumps 1 $50,000 $50,000 New wet well 1 $25,000 $25,000 Wet well coating 1 $8,000 $8,000 New Piping 1 $10,000 $10,000 System Bypass 1 $15,000 $15,000 Misc. Electrical 1 $10,000 $10,000 Construction Subtotal $118,000 Budget Contingency (20%) $23,600 Engineering & Planning (15%) $17,700 Contract Administration 5%) $5,900 s165,200 Vista Del Mar Lift Station - Alternative Project Item Quantity Unit Unit Price Total Price New wet well 1 $20,000 $20,000 Wet well coating 1 $6,000 $6,000 New Piping 1 $10,000 $10,000 System Bypass 1 $10,000 $10,000 Construction Subtotal $46,000 Budget Contingency (20%) $9,200 Engineering & Planning (15%) $6,900 Contract Administration 5%) $2,300 $64,400 Freeway Foothills Lift Station Upgrade Freeway Foothills Lift Station Upgrade Item Quantity Unit Unit Price Total Price New wet well (8' dia x 14' d) 1 $20,000 $20,000 Wet well coating 1 $12,000 $12,000 New Piping 1 $15,000 $15,000 System Bypass 1 $10,000 $10,000 Construction Subtotal $57,000 Budget Contingency (20%) $11,400 Engineering & Planning (15%) $8,550 Contract Administration (5%) $2,850 $79,800 Page 4 of 7 �I St. Andrews Lift Station Stand By Generator and Electrical Upgrades St Andrews Lift Station Stand By Power and Upgrade Electrical System Item Quantity Unit Unit Price Total Price Stand by power system 1 $21,000 $21,000 Electrical improvements 1 $15,000 $15,000 YJ Construction Subtotal $36,000 tBudget Contingency (20%) $7,000 Engineering & Planning (15%) $5,000 Contract Administration (5%) $2,000 (TOTAL PROJECT BUDGET ssa,aaa "1 .l .1� ' #f Page 5 of 7 Sewer Sag Repair Adjacent to Pismo Pier Sag Repair Adjacent to Pismo Pier Item Quantity Unit Unit Price Total Price Replace existing sag in 8" line 650 If $60 $39,000 Sewer lateral (connection only) 1 Is $5,000 $5,000 Construction Subtotal $44,000 Budget Contingency (20%) $9,000 Engineering & Planning (15%) $7,000 Contract Administration (5%) $2,000 TOTAL PRO.iF-CT BUDGET $62,000 Spyglass Lift Station Upgrade Spyglass Lift Station Upgrade Item Quantity Unit Unit Price Total Price System bypass 1 $8,000 $8,000 Stand by power system 1 $45,000 $45,000 Electrical Improvements 1 $25,000 $25,000 Construction Subtotal $78,000 Budget Contingency (20%) $16,000 Engineering & Planning (15%) $12,000 Contract Administration (5%) $4,000 TOTAL PROJECT BUDGET $110,000 PG&E Lift Station Stand By Generator PG&E Lift Station Stand By Generator Item Quantity Unit Unit Price Total Price Stand by power system 1 $10,000 $10,000 System bypass 1 $7,000 $7,000 Construction Subtotal $17,000 Budget Contingency (20%) $3,000 Engineering & Planning (15%) $3,000 Contract Administration (5%) $1,000 TOTAL PROJECT BUDGET $24,000 Page 6 of 7 Sunset Palisades Lift Station Stand By Generator Sunset Palisades Lift Station Stand By Generator Item Quantity Unit Unit Price Total Price Stand by power system 1 $40,000 $40,000 System bypass 1 $7,000 $7,000 Construction Subtotal $47,000 Budget Contingency (20%) $9,000 Engineering & Planning (15%) $7,000 Contract Administration (5%) t? nnn TOTAL PROJECT BUDGET ., $65,0001 Vista Del Mar Gravity System Upgrade Vista Del Mar GravU System Upgrade Item Quantity Unit Unit Price Total Price Replace existing 8" line with 10" 1100 If $70 $77,000 Sewer laterals (connection only) 1 Is $5,000 $5,000 Construction Subtotal $82,000 Budget Contingency (20%) $16,000 Engineering & Planning (15%) $12,000 Contract Administration (5%) $4,000 TOTAL PROJECT BUDGET $114,000 Pismo Oaks Gravity System Upgrade Pismo Oaks Gravity System Upgrade Item Quantity Unit Unit Price Total Price 12" gravity sewer 2000 If $75 $150,000 Sewer Laterals 27 ea $1,600 $43,200 Connections 1Is $5,000 $5,000 System bypass 1 Is $15,000 $15,000 Construction Subtotal $213,200 Budget Contingency (20%) $43,000 Engineering & Planning (15%) $32,000 Contract Administration (5%) $11,000 TOTAL PROJECT BUDGET $299,200 Page 7 of 7