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HomeMy WebLinkAbout; Vallecitos Water District Treatment & Pollution; Vallecitos Water District Treatment & Pollution; 1995-10-182343 SAN ELIJO AVENUE, CARDIFF BY THE SEA, CALIFORNIA 92007 • 619-942-0676 • FAX 619-942-0677 October 18, 1995 Mr. William Rucker f* General Manager IH VALLECITOS WATER DISTRICT 788 San Marcos Boulevard m San Marcos, California 92069 IM Subject: Sale of Vallecitos Water Distria Treatment and Disposal Capacity at the Encina Water m Pollution Control Facility ta Dear Mr. Rucker: jL This attached report presents our findings with respect to contractual and financial impacts associated with the sale of Vallecitos Water Distria (District) capacity at the Encina Water Pollution Control __ Facility's (EWPCF) pursuant to our proposal of April 6, 1995. The report has been prepared with |y District input, as well as the input of the Encina Wastewater Authority (EWA) staff. Two draft versions of the report were reviewed and commented upon by both District and EWA staffs. I. The six sections of the report are summarized as follows:i* _ Section 1: Review of Existing Agreements™ la It was determined that the existing EWA agreements appear to allow the District to withdraw from EWA and sell its capacity to any member agency or agencies, at the District's sole discretion. The P* terms and conditions of the sale appear to be the concern and responsibility of only the District and Ig the participating agency or agencies. P Section 2: Determination of Future Capacity Needs Recently generated member agency growth data was used to determine the existing life span of EWPCF treatment and disposal capacity. Given high peaking during winter storms of 1995, a peaking *^ factor of 3.0 was evaluated in addition to the 2.5 peaking factor previously used by EWA planning ^ documents. The following table summarizes the time when Encina Water Pollution Control Facility (EWPCF) treatment, hydraulic and disposal capacities would be exceeded. l^W i P p m m,• 4m Mr. William Rucker October 18, 1995 Page 2 Life Span ofEWPCF Treatment, Hydraulic and Disposal Capacity EWPCF Treatment Capacity EWPCF Hydraulic Capacity 2.5 Peaking Factor 3.0 Peaking Factor EWPCF Disposal Capacity 2.5 Peaking Factor 3.0 Peaking Factor With VWD 2012 2022 2014 2005 1999 Without VWD 2028 >2030 >2030 2015 2005 pft to Section 3: Determination of Capital Improvements The costs associated with the construction of the necessary treatment and disposal capacity necessary to meet the ultimate EWPCF demands were determined using existing planning documents. These costs are summarized in the following table. Capital Costs of Future Facilities Administrative Facilities Treatment Facilities: Process Hydraulic Throughput Disposal Facilities With Pathogen Limits Without Pathogen Limits Total** With Pathogen Limits Without Pathogen Limits With VWD * $31,284,000 Unknown $43,520,000 $35,811,000 $74,804,000 $67,095,000 Without VWD * $8,412,000 Unknown $11,937.000 $7,848,000 $20,349,000 $16,260,000 Cost of Administrative Facilities unknown at this time. * Excluding cost to provide additional hydraulic throughput capacity. ENRLA: 6513 m Section 4: Scheduling of Expansion Capacity It was determined that the planning and construction of effluent disposal were on the critical path of meeting ultimate EWPCF capacity. The following alternatives are considered in existing EWA documents as viable means of meeting the ultimate disposal capacity requirement. Mr. William Rucker October 18,1995 Page 3 Alternate 3: Replace existing 48-inch-diameter outfall with a 72-inch-diameter outfall, provide 2-million gallons of flow equalization and provide effluent pumping. Alternate 3b: Replace existing 48-inch-diameter outfall with a 72-inch-diameter outfall, provide 2-million gallons of flow equalization, provide effluent pumping and provide disinfection facilities. Alternate 4: Provide flow equalization and effluent pumping. Alternate 4b: Provide flow equalization, effluent pumping and disinfection facilities. The following table presents the timeframe under which the EWA must begin planning for the various expansion scenarios being considered. Required Year of Project Start to Meet Capacity Limitation 2.5 Peaking Factor WithVWD Alt.3 2000 Alt.3b 1998 Without VWD Alt.4 2011 Alt.4b 2009 3.0 Peaking Factor WithVWD Alt.3 NOW Alt.3b NOW Without VWD Alt.4 2001 Alt.4b 1999 Section 5: Assumptions Impacting Future Expansion Planning The major consideration impacting future planning is the determination of a peaking factor. Research has determined that the Phase IE Expansion was implemented assuming a peaking factor of 2.1. More recent EWA planning has used a 2.5 peaking factor. Recent storms, in early 1995, indicate that a peaking factor of 3.0 may be appropriate. As can be seen in Sections 3 and 4, the difference between a peaking factor of 2.5 and 3.0 is very significant in terms of cost of future facilities, as well as the time when such facilities would be needed. It appears that the only viable means of dealing with peaking is by providing treatment as required, or by taking steps to reduce inflow and infiltration into member agency sewer lines. The choice should be based on a comparison of the practicality and cost effectiveness of the two methods. Mr. William Rucker October 18, 1995 Page 4 Legislation working its way through Congress may allow the EWPCF to revert to advanced primary treatment. Should this legislation ever become law, the EWA may consider the financial advantages of pursuing a waiver from secondary treatment. Obviously, should advanced primary treatment be opted for, the EWA planning process will have to be redone. Section 6: Financial Impacts of Withdrawal It was determined that, should the District withdraw from the EWA, the savings to the remaining EWA member agencies would be $13.6 million (without effluent disinfection) or $14.6 million (with effluent disinfection) depending upon the institution of pathogen limits. The value of VWD capacity at the EWPCF may be determined several ways, including the book value, replacement value, or value set forth in the Revised Basic Agreement for capacity infringements. The following table sets forth VWD's EWPCF capacity value per the methods described. VWD EWPCF Capacity Value Method Book Replacement Capacity Infringement Value $22.1 million $26.9 million $31 .8 million The information provided in the report may be used as the basis for District's consideration of the sale of its EWPCF capacity. However, EWA's ongoing planning process may change some of the data presented herein. It is highly recommended that the District continuously monitor and participate in EWA planning efforts to assure itself of the most up-to-date information. We are available at your convenience to meet with the District's Board of Directors and staff, EWA staff, and EWA member agencies to discuss the findings of this report. As always, it has been extremely rewarding working with the District. Thank you for the opportunity to be of service. Very truly yours, THE NCG GROUP S.Murk icipal Attachment FINAL REPORT SALE OF VALLECITOS WATER DISTRICT TREATMENT AND DISPOSAL CAPACITY AT ENCINA WATER POLLUTION CONTROL FACILITY PREPARED BY THE NCG GROUP 2343 SAN ELMO AVENUE CARDIFF BY THE SEA, CALIFORNIA 92007 619-942-0676 PREPARED FOR , VALLECITOS WATER DISTRICT ** 788 SAN MARCOS BOULEVARD m SAN MARCOS, CALIFORNIA 92069 OCTOBER 1995 SECTION 1: REVIEW OF EXISTING AGREEMENTS The Revised Basic Agreement, dated November 9, 1994, specifically supports the sale or lease of VWD capacity to any member agency or member agencies in Section 8. Section 8 states... "Such lease or purchase shall be on the terms as are hereafter agreed upon by the member agencies involved." No reference is made to nor implies the inclusion or approval of nonparticipating member agencies in the transaction. It appears that the only responsibility of the agencies involved in the transaction is as follows ... "In the event an inter-agency capacity agreement is adopted, the Joint Advisory Committee shall be notified in writing." Section 8 further states ..."Licensing, lease or purchase shall be subject to the terms and conditions established in Section 9 herein." However, inspection of Section 9 indicates no apparent terms or conditions imposed upon lease or sale of capacity. Section 9.1 sets forth the member agencies' Unit I and Unit J capacity rights, while Section 9.2 deals solely with capacity infringements and the administration of a reserve capacity pool to deal with such infringements. The costs for capacity as set forth in Section 9e, License Payments, refer exclusively to remedying capacity infringements, and not to voluntary buy/sell agreements between member agencies conducted per Section 8. The Revised Establishment Document for the Encina Wastewater Authority, dated November 9, 1994, addresses the issue of member agency withdrawal in Section 2.11. Section 2.11 calls for the"... partial or complete distribution of assets and discharge of liabilities as follows. The distribution of assets may be made in kind or assets may be sold and the proceeds thereof distributed to a member agency at the time of withdrawal..." Section 2.11.1 specifically addresses the withdrawal issue, again calling for the receipt of assets and contribution towards liabilities by the withdrawing member agency. No other references to withdrawal are found in the Revised Establishment Document. Therefore, it can be concluded that the District appears to have the right to withdraw from the EWA and sell or lease its capacity to any other member agency or member agencies, under terms and conditions negotiated with said member agency(ies) and need not obtain consent nor approval from nonparticipating member agencies. SECTION 2: DETERMINATION OF FUTURE CAPACITY NEEDS m * V in To date, the February 1993 2020 Facility Plan Update prepared by John Carollo Engineers and the April 1992 Ocean Outfall Facility Plan prepared by Greeley and Hansen/Arber Associates have been used by the Encina Wastewater Authority (EWA) as the basis for planning decisions. However, recent conversations with EWA staff, indicate that the intense rain storms of 1995 have necessitated a re-examination of the wet weather flow and peaking factor assumptions used in the 2020 Facility Plan Update and the Ocean Outfall Facility Plan. It should be noted that the growth and planning information used to produce the 2020 Facility Plan Update and the Ocean Outfall Facility Plan was obtained from the member agencies. For the purpose of this report, the 2020 Fac/% Plan Update and the Ocean Outfall Facility Plan will be used as the prime reference documents. However, current input from EWA staff relative to modifications resulting from the recent storms and recently revised ultimate flow forecasts from the member agencies will also be addressed and included as appropriate. (Attachment 1.) 2.1 DRY WEATHER FLOW CONSIDERATIONS The following table, based upon the data contained in Attachment 1, presents the currently projected average daily dry weather flows (addwf) in millions of gallons per day (mgd) as influent flow to the Encina Water Pollution Control Facility (EWPCF). TABLE 2-1 PROJECTED DRY WEATHER FLOWS AS INFLUENT TO ENCINA WATER POLLUTION CONTROL FACILITY YEAR 1995 2000 2005 2010 2015 2020 2025 2030 FLOW WITH VWD (mgd addwf) 21.0 25.6 30.2 34.9 39.5 44.1 48.7 53.4 FLOW WITHOUT VWD (mgd addwf) * 21.5 24.1 26.6 29.1 31.7 34.2 36.8 VWD withdrawal assumed to take place in the year 2000. 2-1 FIGURE 2-1 INFLUENT DRY WEATHER FLOW Figure 2-1 is the graphical presentation of the data presented in Table 2-1, with the addition of the current EWPCF liquid treatment capacity of 36.0 million gallons per day addwf. Examination of Figure 2-1 indicates that existing EWPCF treatment capacity is adequate for member agency needs through the years 2012 and 2028, with the VWD as a member, and without VWD as a member, respectively. 2.2 WET WEATHER FLOW CONSIDERATIONS »-^i-__'4 . J~ 1.— «^U-. FLOW w/VWD i FLOW ; wcWWDTRBUMBTT CAPAOTY Peak wet weather flow data were calculated using Table 2-1 as the basis. Flows were peaked using a 2.5 factor, with the exception of the flow from the Meadowlark Water Reclamation Facility, which was peaked at a factor of 1.1 due to the availability of the Mahr Reservoir to store excess flow. Table 2-2 presents the forecasted peak wet weather flows (pwwf). The values presented in Table 2-2 include excess reclaimed water from the Gafner, Shadowridge, and Meadowlark facilities. For analysis, it is assumed that the total flow to the reclamation facilities will be discharged to their respective failsafe outfalls, and subsequently be discharged to the Encina ocean outfall during a peak storm event. 2-2 TABLE 2-2 2.5 PEAKING FACTOR PROJECTED WET WEATHER FLOWS INCLUDING RECLAMATION PLANTS DISCHARGED TO ENCINA OCEAN OUTFALL YEAR 1995 2000 2005 2010 2015 2020 2025 2030 FLOW WITH VWD (mgd pwwf) 57.9 69.8 81.8 93.7 105.7 117.6 129.6 141.5 FLOW WITHOUT VWD (mgd pwwf) * 60.9 66.9 72.8 78.8 84.8 90.7 96.7 VWD withdrawal assumed to take place in the year 2000. Figure 2-2 is the graphical presentation of the data presented in Table 2-2, with the addition of the current disposal capacity of 80.0 million gallons per day pwwf. The peak disposal capacity 80.0 mgd was determined by peaking the 32.0 mgd addwf capacity, which includes both flow equalization and ocean outfall capacity, by 2.5. The ocean FIGURE 2-2 outfall capacity was determined OCEAN OUTFALL PEAK WET WEATHER FLOW using a calculated, not measured, 2.5 FACTOR friction factor. For this reason the IGO.O EWA will be conducting a field uo.o investigation to determine the "s actual friction factor. Therefore, t. the 80.0 mgd pwwf disposal ?, capacity is subject to change •§ based upon the results of the § current study. Examination of ul Figure 2-2 indicates that existing EWPCF disposal capacity, combined flow equalization, and ocean outfall capacity is adequate for member agency needs through the years 2005 and 2015, with the VWD as a member and without VWD as a member, respectively. .FLOWwA/WD .FLOWwo/VWD . DISPOSAL CAPACfTY 2-3 It should be noted that during the Phase III expansion planning process, it was decided to use a wet weather peaking factor of approximately 2.1. Reference Figure 4-12 of Brown and Caldwell's February 1975 Phase III Enlargement and Upgrading ofEncina Water Pollution Control Facilities. The 2.1 peaking factor yielded an peak wet weather flow of approximately 92 mgd pwwf, based upon a 45 mgd addwf. It was subsequently determined that the EWPCF has a peak hydraulic capacity of 115 mgd based upon existing process design and configuration. Figure 2-2a presents a plot of the limiting existing hydraulic capacity on the projected wet weather flows entering the EWPCF plant headworks. FIGURE 2-2a INFLUENT PEAK WET WEATHER FLOW 2.5 FACTOR 140.0 .FLOWw/VWD -FLOWwo/VWD .WFLUBTTHYDRAULC CAPACfTY : •«- CM CM As can be seen on Figure 2-2a, the plant's hydraulic capacity is exceeded in the year 2022 with the VWD as a member of the EWA. Therefore, not only is the disposal capacity potentially limiting, so to is the EWPCF's hydraulic capacity. Discussions with EWA staff indicate that the observed peaking factor during the storms of early 1995 was as high as 3.0. This fact further stresses the existing plant hydraulic capacity and ocean outfall disposal capacity and, therefore, this peaking factor must be examined in light of the goals of this study. In order to determine the impact of a 3.0 peaking factor upon the existing EWPCF, Table 2-3 was constructed by peaking the flow projections presented in Table 2-1 by a factor of 3.0. 2-4 TABLE 2-3 3.0 PEAKING FACTOR PROJECTED WET WEATHER FLOWS INCLUDING RECLAMATION PLANTS DISCHARGED TO ENCINA WATER OCEAN OUTFALL YEAR 1995 2000 2005 2010 2015 2020 2025 030 FLOW WITH VWD (mgd pwwf) 69.0 83.3 97.6 111.9 126.2 140.5 154.8 169.1 FLOW WITHOUT VWD (mgd pwwf) * 73.1 80.3 87.4 94.6 101.7 108.9 116.0 VWD withdrawal assumed to take place in the year 2000 Figure 2-3 presents the Table 2-3 data graphically. Examination of Figure 2-3 indicates that existing EWPCF disposal capacity, combined flow equalization, and ocean outfall capacity is adequate for member agency needs through the years 1999 and 2005, with the VWD as a member and without VWD as a member, respectively. FIGURE 2-3 OCEAN OUTFALL PEAK WET WEATHER FLOW 3.0 FACTOR Figure 2-3a was constructed to examine the plant's hydraulic capacity limitation given the 3.0 peaking factor. Examination of Figure 2-3a indicates that the EWPCF hydraulic capacity is adequate for member agency needs through the years 2014 and 2035, with the VWD as a member and without VWD as a .FLOWw/VWD .FLOWwo/VWD . DISPOSAL CAPAOTY 2-5 member, respectively. Therefore, it will be necessary to consider both hydraulic and disposal capacity needs in upcoming planning endeavors if the 3.0 peaking factor is borne out. FIGURE 2-3a INFLUENT PEAK WET WEATHER FLOW - 3.0 FACTOR 180.0 160.0 .FLOWw/VWD .R-OWwo/VWD .KFLUB^ HYDRAULIC j CAPACTTY o in o in o*- T- CM CM CO CM CM CM CM CM YEAR 2-6 SECTION 3: DETERMINATION OF CAPITAL IMPROVEMENTS The 2020 Facility Plan Update and the April 1992 Ocean Outfall Facility Plan prepared by Greeley and Hansen/Arber Associates present the currently recommended capital improvements to meet the treatment and disposal needs, respectively, of the EWA through ultimate build out. Both documents were prepared considering the possible withdrawal of the VWD from the EWA. 3.1 ADMINISTRATION FACILITIES The 2020 Facility Plan Update recommends the following administrative facilities: TABLE 3-1 ENCINA WATER POLLUTION CONTROL FACILITY ADMINISTRATIVE FACILITY REQUIREMENTS FACILITY ADMINISTRATION BUILDING OPERATIONS/MAINTENANCE PARKING WITH VWD * 13,000 square feet 50,400 square feet WITHOUT VWD * 13,000 square feet 28,000 square feet * administration building sizing and costs are under consideration. 3.2 TREATMENT FACILITIES 3.2.1 PROCESS CAPACITY The following table presents the recommended unit process additions for the EWPCF under the with , and without VWD alternatives. The data for Table 3-2 was taken from the 2020 Facility Plan Update. 3-1 TABLE 3-2 ENCINA WATER POLLUTION CONTROL FACILITY UNIT PROCESS REQUIREMENTS UNIT PROCESS Bar Screens Grit Chambers Primary Clarifiers Aeration Basins Secondary Clarifiers DAF Thickeners Digesters Small Large Belt Presses EXISTING NUMBER 4 3 10 3 7 3 3 3 4 ADDITIONAL UNITS withVWD (Alternative 1B) 2 1 5 1* 3** 1 0 2 0 ADDITIONAL UNITS without VWD (Alternative 2C) 0 0 0 0 1 0 0 1 0 Outfit only. ** Outfit 1 tank, construct two tanks. The construction of the Alternative 1B facilities, which include the VWD, described in Table 3-2, increases the rated capacity of the EWPCF to 53.7 mgd. In order to determine the capital costs associated with the treatment processes associated with Alternatives 1B and 2C, it was necessary to utilize the cost data presented in the 2020 Facility Plan prepared in 1988 by JCE, as it was not part of JCE's scope to develop cost data in the 2020 Facility Plan Update. Unit costs for the appropriate treatment processes, using Alternative S-1 of the 2020 Facility Plan, were updated to a current ENRLA of 6513. 3.2.2 HYDRAULIC THROUGHPUT CAPACITY As previously discussed, the hydraulic throughput capacity of the plant is 115 mgd. Utilizing a peaking factor of 2.5 or 3.0 results in the need to increase the EWPCF's hydraulic throughput capacity in the event the VWD continues participation in the EWA. Alternative means of providing hydraulic through-put capacity in excess of 115 mgd have not yet been developed, therefore it is not possible to estimate any costs associated with providing the needed additional capacity. 3.3 DISPOSAL FACILITIES The Ocean Outfall Facility Plan recommends the replacement of the 48-inch section of the 3-2 existing outfall with a 72-inch pipe and the addition of 2 million gallons of flow equalization capacity, assuming continued VWD participation, which has been designated as Alternative 3b. This alternative includes the provision of disinfection facilities to assure compliance with possible pathogen limits. As previously discussed, the EWA is currently undertaking an outfall flow study to confirm the actual friction factor. Given the magnitude of the Alternative 3b project in terms of cost and environmental considerations, the use of an accurate "n" factor is essential. Without continued VWD participation, the Ocean Outfall Facility Plan recommends the addition of 3 million gallons of flow equalization capacity, as well as the retention of the Phase IV interim capacity, designated as Alternative 4b. This alternative also assumes that pathogen limits will be imposed upon the discharge. The recommended alternatives in the Ocean Outfall Facility Plan were based on a peaking factor of 2.5. As discussed under Task 2, the actual design peaking factor may be as high as 3.0. Therefore, if the 3.0 peaking factor is confirmed, it will be necessary to (1) reduce the peaking factor by the member agency control of inflow and infiltration, or (2) prepare a revised ocean outfall facility plan to accommodate the 3.0 peaking factor. The EWA is currently in the process of performing an outfall flow analysis. Upon completion of the outfall flow analysis, an update of the current Ocean Outfall Facility Plan is planned. However, for the purpose of this study, it will be assumed that the existing Ocean Outfall Facility Plan is operative. 3.4 SUMMARY OF CAPITAL COSTS The following table presents a summary of the capital costs associated with the implementation of the recommended administrative, treatment, and disposal facilities: TABLE 3-3 COST OF IMPLEMENTATION ADMINISTRATION FACILITIES TREATMENT FACILITIES- PROCESS HYDRAULIC THROUGH-PUT DISPOSAL FACILITIES WITH PATHOGEN LIMITS WITHOUT PATHOGEN LIMITS TOTAL" WITH PATHOGEN LIMITS WITHOUT PATHOGEN LIMITS WITH VWD * $31,284,000 UNKNOWN $43,520,000 $35,811,000 $74,804,000 $67,095,000 WITHOUT VWD * $8,412,000 UNKNOWN $11,937,000 $7,848,000 $20,349,000 $16,260,000 Cost of Administrative Facilities unknown at this time. ' Excluding cost to provide additional hydraulic throughput capacity. ENRLA: 6513 3-3 It should be noted that the existing hydraulic capacity of the EWPCF is 115 mgd, while the projected peak flow, based upon a peaking factor of 2.5, is estimated to be 134.3 mgd as shown on Table 2-2. A conversation with Dennis Wood of John Carollo Engineers indicates that no consideration, with respect to facilities required or cost thereof was given to accommodate the differential between the existing EWPCF hydraulic capacity and the projected peak flow. 3-4 SECTION 4: SCHEDULING OF EXPANSION CAPACITY 4.1 CAPACITY OF EXISTING FACILITIES The EWPCF has the ability to successfully process flows through the time frames as set forth in Table 4-1. TABLE 4-1 ENCINA WATER POLLUTION CONTROL FACILITY YEAR CAPACITY WOULD BE EXCEEDED TREATMENT CAPACITY HYDRAULIC CAPACITY 2.5 PEAKING FACTOR 3.0 PEAKING FACTOR DISPOSAL CAPACITY 2.5 PEAKING FACTOR 3.0 PEAKING FACTOR WITHVWD 2012 2022 2014 2005 1999 WITHOUT VWD 2027 >2030 >2030 2015 2005 *VWD withdrawal assumed to take place in the year 2000. 4.2 IMPLEMENTATION OF IMPROVEMENTS As part of the April 1992 Ocean Outfall Facility Plan prepared by Greeley and Hansen/Arber Associates, a detailed "Long-term Effluent Disposal Flowchart" (Figure 5) was prepared. This flowchart provides the processes, as well as the estimate of time associated with the various processes necessary to implement a variety of options to satisfy long-term disposal capacity needs. The recommended disposal options with and without VWD are Alternative 3b, and Alternative 4b, respectively. Alternative 3b involves the replacement of the 48-inch section of the outfall with a 72-inch outfall, the provision of 2 million gallons (mg) of flow equalization capacity, and the provision of disinfection facilities. Alternative 4b calls for 4 mg of new flow equalization capacity in conjunction with the retention of flow equalization capacity created in the Phase IV expansion and the provision of disinfection facilities. Alternatives 3 and 4 are identical to 3a and 4b with the exception that no disinfection facilities are provided. The Long-Term Effluent Disposal Flowchart estimates 6-7 years for the implementation of Alternative 3b, and 5-6 years for the implementation of Alternative 4b. Table 4-2 presents the starting year for each alternative given the Long-Term Effluent Disposal Flowchart estimate to implement. 4-1 TABLE 4-2 ENCINA WATER POLLUTION CONTROL FACILITY REQUIRED YEAR OF PROJECT START TO MEET CAPACITY LIMITATION 2.5 PEAKING FACTOR WITHVWD ALT. 3 2000 ALT. 3b 1998 WITHOUT VWD ALT. 4 2011 ALT. 4b 2009 3.0 PEAKING FACTOR WITHVWD ALT. 3 NOW ALT. 3b NOW WITHOUT VWD ALT. 4 2001 ALT. 4b 1999 4-2 SECTION 5: ASSUMPTIONS IMPACTING FUTURE EXPANSION PLANNING The information presented in Sections 2, 3, and 4 is based upon certain assumptions that require close examination given the cost and timing of the current EWPCF expansion plans. It appears that the most significant assumptions involve the wet weather peaking factor and the type of treatment employed at the EWPCF. 5.1 PEAKING FACTOR CONSIDERATIONS As discussed, in 1975 when B&C prepared the Phase III expansion design, a peaking factor of 2.1 was considered adequate and appropriate. History has shown this value to be low, and now peaking factors in the range of 2.5 to 3.0 are considered reasonable. There are three basic ways of dealing with wet weather peaking: 1. Reduce inflow and infiltration into the sewer system. 2. Equalize flow, either in the sewer system or at the treatment facilities. 3. Treat and dispose of the flow as it occurs. Each of these methods will be analyzed and discussed as it applies to the EWPCF's situation. 5.1.1 Inflow and infiltration reduction The resolution of the inflow and infiltration (l&l) issue should be made on economic terms - determine the unit cost of l&l reduction and compare it to the unit cost of treatment and disposal, then compare the two costs and implement the least costly. This approach was taken by B&C in the 1975 Phase III Enlargement and Upgrading ofEncina Water Pollution Control Facilities. Figure 4-9 of the 1975 B&C report presented the finding, valid at that time, that treatment and disposal was more cost effective than taking rehabilitation measures such as sealing manholes and grouting known leaks. However, given the magnitude of the present peaking factor, it appears that an analysis comparing treatment and disposal versus l&l control should be considered. Reduction of l&l may be especially critical in light of the existing EWPCF's plant hydraulic capacity limitation of 115 mgd. 5.1.2 Flow equalization Flow equalization that would be effective in overcoming the EWPCF's hydraulic capacity limitation of 115 mgd would have to occur prior to the treatment plant. This means that raw sewage would have to be flow equalized at a facility, or facilities, located on the major incoming sewer lines. This approach is probably not practical, nor cost effective from several considerations. Given the flow equalization of raw sewage that would be required, sophisticated flow equalization facilities would be required to contain odors and to resuspend settled solids. Such facilities would be costly, require considerable land, and necessitate high labor input. 5-1 As the flow to the EWPCF comes in via several lines, more than one flow equalization facility would be required, thereby compounding the problems and costs encountered. 5.1.3 Treat and dispose of the flow The selection of this option would be determined upon the results of its comparison on a cost basis to the l&l control strategies previously discussed. Depending upon the magnitude of the peaking factor selected for design, the availability of land at the EWPCF may become a controlling consideration. Additionally, it will also be necessary to devise a plan to overcome the hydraulic capacity limitation of 115 mgd. 5.2 TREATMENT CONSIDERATIONS Currently, the EWPCF is designed to treat and dispose of secondary effluent. However, legislation is being considered to allow the discharge of chemically treated primary effluent through ocean outfalls that are at least 150 feet deep and 1 mile offshore. This proposed legislation, which is included as Attachment 2, would provide a ten year "waiver." Should this proposed legislation become law, it presents the EWA with a potentially cost effective means of handling wet weather peak flows, as well as terminating secondary treatment altogether. Peak wet weather flows could be handled by shunting flows above a predetermined level through a chemical treatment system, achieving an advanced primary level of treatment, and then combining chemically treated flow with the secondary flow for discharge to the ocean. The cost of a chemical treatment system would be significantly less than an equivalent amount of secondary treatment capacity. Chemical treatment would also be more readily able to handle unannounced flow increases, than would biological process systems resulting in a more reliable treatment process train. The proposed legislation also raises the issue of whether or not the EWPCF produce secondary effluent for ocean discharge. In the event the EWA chooses to operate in the advanced primary mode, the currently proposed expansion, which is biologically based secondary treatment, would have to be completely rethought. It is almost a certainty that an advanced primary expansion would cost less than what is currently planned. The question is how much less. 5-2 SECTION 6: FINANCIAL IMPACTS OF WITHDRAWAL This section will present the financial impacts of a VWD withdrawal from the EWA assuming the September 1995 revisions are operative. The financial impacts must be examined from two standpoints - the avoided costs associated with future expansions to meet the needs of all member agencies, including VWD, and the value of VWD's existing owned capacity in the EWPCF. 6.1 EXISTING AND PROJECTED CAPACITY RIGHTS The basis for the analysis is the respective ownership of the EWPCF as set forth in the Revised Basic Agreement. Ownership in the EWPCF is broken down into two major categories; Unit I which includes liquid and solid treatment, and Unit J which includes ocean disposal. The following table presents the existing capacity rights as set forth in the Revised Basic Agreement. TABLE 6-1 ENCINA WATER POLLUTION CONTROL FACILITY CAPACITY RIGHTS VISTA CARLSBAD BUENA VALLECITOS LEUCADIA ENCINITAS TOTAL UNIT I LIQUID mgd 8.05 9.24 2.26 7.54 7.11 1.80 36.00 % 0.22 25.67% 6.28% 20.94% 19.75% 5.00% 100.00% SOLIDS mgd 8.05 9.24 3.51 7.54 7.86 1.80 38.00 % 21.18% 24.32% 9.24% 19.84% 20.68% 4.74% 100.00% UNIT J* DISPOSAL mgd 8.05 9.24 3.51 7.54 7.86 1.80 38.00 % 0.21 24.32% 9.24% 19.84% 20.68% 4.74% 100.00% •Assumes 2.1 peaking factor. In order to evaluate the impact of VWD withdrawal, examination of projected capacity requirements is necessary. The following table presents the projected ultimate capacity requirements as set forth in the September 1995 revisions. 6-1 TABLE 6-2 ENCINA WATER POLLUTION CONTROL FACILITY PROJECTED ULTIMATE CAPACITY REQUIREMENTS VISTA CARLSBAD BUENA VALLECITOS LEUCADIA ENCINITAS TOTAL UNITI LIQUID mgd 10.50 13.40 3.52 16.60 7.11 1.80 53.37 % 19.67% 25.93% 6.60% 31.10% 13.32% 3.37% 100.00% SOLIDS* mgd 10.50 13.84 4.77 19.60 7.86 1.80 58.37 % 17.99% 23.71% 8.17% 33.58% 13.47% 3.08% 100.00% UNITJ DISPOSAL mgd 10.50 13.84 4.68 19.60 7.86 1.80 58.28 % 18.02% 23.75% 8.03% 33.63% 13.49% 3.09% 100.00% ASSUMES BUENA AND LEUCADIA RETAIN ADDITIONAL 1.25 MGD AND 0.75 MGD SOLIDS CAPACITY. RESPECTIVELY As can be seen by comparing Tables 6-1 and 6-2, there is a significant change in the respective levels of ownership among the member agencies. In order to determine the proportionate cost of the proposed expansions of treatment and disposal capacity for the respective member agencies, the following table has been created. TABLE 6-3 ENCINA WATER POLLUTION CONTROL FACILITY SHARE OF FUTURE EXPANSION VISTA CARLSBAD BUENA VALLECITOS LEUCADIA ENCINITAS TOTAL UN LIQUID mgd 2.45 4.60 1.26 9.06 0.00 0.00 17.74 % 14.10% 26.48% 7.25% 52.16% 0.00% 0.00% 100.00% Tl SOLIDS* mgd 2.45 4.60 1.26 12.06 0.00 0.00 20.37 % 12.03% 22.58% 6.19% 59.20% 0.00% 0.00% 100.00% UNITJ DISPOSAL mgd 2.45 4.60 1.17 12.06 0.00 0.00 20.65 % 12.08% 22.68% 5.77% 59.47% 0.00% 0.00% 100.00% ASSUMES BUENA AND LEUCADIA RETAIN ADDITIONAL 1.25 MGD AND 0.75 MGD SOLIDS CAPACITY, RESPECTIVELY. 6-2 6.2 FUTURE COSTS 6.2.1 PROJECT COSTS Using the data presented in Table 6-3 and capital costs presented in Table 3-3, the following table was constructed to show the costs to the VWD and the other EWA member agencies for the with VWD and without VWD scenarios. TABLE 6-4 APPROPRIATED COST OF IMPLEMENTATION TREATMENT FACILITIES DISPOSAL FACILITIES WITH PATHOGEN LIMITS WITHOUT PATHOGEN LIMITS TOTAL WITH PATHOGEN LIMITS WITHOUT PATHOGEN LIMITS WITH VWD MEMBER AGENCY COST $16,318,000 $17,639,000 $14,514,000 $33,957,000 $30,832,000 VWD COST $14,997,000 $25,881,000 $21,297,000 $40,878,000 $36,294,000 WITHOUT VWD MEMBER AGENCY COST $8,412,000 $11,937,000 $7,848,000 $20,349,000 $16,260,000 6.2.2 AVOIDED COSTS Examination of Table 6-4 indicates that withdrawal of the VWD from EWA may result in a savings of $13.6 million or $14.6 million, depending on whether or not pathogen limits are enforced, to the remaining member agencies for construction of the currently planned treatment and disposal facilities. The VWD avoids a cost of $40.9 million or $36.3 million, again depending on whether or not pathogen limits are enforced, which is its share of the EWA treatment and disposal facilities, by withdrawing. Therefore, the total avoided cost caused by a VWD withdrawal is approximately $54.5 million, or $50.9 million, depending upon enforcement of the pathogen limits. 6.3 EXISTING CAPACITY VALUE The VWD currently owns the portion of the EWA facilities as set forth in Table 6-1. Upon withdrawal, the VWD is entitled to consideration for the value of these facilities. While the Revised Basic Agreement does not provide for a direct method of determining the capital value of its member's assets, it does provide an indirect method of valuation. As previously discussed, Section 9 of the Revised Basic Agreement deals with the value of existing capacity. While the intent of Section 9 is to resolve capacity infringements, it may be reasonable to use 6-3 the formula set forth in Section 9e, License Payments, to determine the capital value of existing capacity. Under Section 9e(1), the following values are set forth: $ 84,000 per mgd of Unit I liquid capacity per year $133,000 per mgd of Unit I solids capacity $ 36,000 per mgd of Unit J capacity per year. The values set forth above are intended to serve as the basis for annual lease payments made by a member agency, temporarily out of capacity to a member agency, or agencies, with excess capacity. Section 9e(2) provides for a significantly higher annual payment should reserve capacity in excess of 50% be used, however, for the purpose of this report these values were not considered. In order to convert the annual values of liquid, solids, and disposal capacity to a capital value, it is necessary to decide upon a discount rate, and then capitalize the annual value. For the purpose of this report, a discount rate of six percent will be used. The six percent value is based upon the sum of an historical true interest rate of three percent, and an assumed inflation rate of three percent. The capitalized value of existing VWD ownership is shown in the following table. TABLE 6-5 CAPITALIZED VALUE OF EXISTING VWD CAPACITY LIQUID CAPACITY SOLIDS CAPACITY DISPOSAL CAPACITY TOTAL CAPITALIZED VALUE $10,556,000 $16,714,000 $4,524,000 $31,794.000 Additionally, the Phase IV Cost Allocation Update dated July 27, 1995 prepared by John Carollo Engineers, and revised by a facsimile transmission dated September 7, 1995, presents the book and replacement values of the various EWPCF components. Table 6-6 summarizes the these values. 6-4 TABLE 6-6 BOOK AND REPLACEMENT VALUES OF EXISTING VWD CAPACITY LIQUID CAPACITY SOLIDS CAPACITY DISPOSAL CAPACITY TOTAL BOOK VALUE $19,494,000 INCLUDED IN LIQUID $2,579,000 $22,073,000 REPLACEMENT VALUE $22,782,000 INCLUDED IN LIQUID $4,148,000 $26,930,000 6-5 ATTACHMENT 1 Projected Ultimate Flows Encinas Water Pollution Control Facility Member Agency Vista Carlsbad Leucadia Gafner Vallecitos Meadowlark Buena Shadowridge Encinitas Total average w/ VWD PWWF w/VWD m Total average w/o VWD PWWF w/o VWD m 1993 EWPCF Influent (mgd) 10.50 13.40 8.85 - 15.72 - 3.47 - .1.80 53.74 134.30 38.02 95.00 1995 EWPCF Influent {mgd) 10,50 13.84 7.11 - 16.60 - 3.52 - 1,80 53.37 160.11 36.77 110.31 1993 Fail Safe Disposal (mgd) 10.50 13.40 8.85 0.75 15.72 3.0 3.47 1.16 JI.80 58.65 142.40 39.93 99.80 1995 Fail Safe Disposal (mgd) 10.50 13.84 7.11 0.75 16.60 3.0 3.52 1.16 JLfiQ 58.28 174.84 38.68 116.04 (1> PWWF in 1993 based on peaking factor of 2.5. PWWF in 1995 based on peaking factor of 3.0 Itr1045 £0'd £6t?il£t?6l9 'ON H31VM31SVM VNION3 NOW 96-8t-d3S ATTACHMENT 2 .'sENT V. USD EXEC. OFFTCE; 6-26.95 4:^; 3,0 695 8660 ., 6,99420677; | 74 1 (b) REPORTING.—Section 305(b) (33 U.S.C. 2 1315(b)) is amended— • , 3 (1) in paragraph (1) by striking the matter pre- 4 ceding subparagraph (A) and inserting "Not later# 5 than 3 years after the date of the enactment of the • „ 6 Clean Water Amendments of 1995, and even' 5 7 years thereafter, each State shall prepare and sub- **8 mit to the Administrator a report which shall in- m m 9 elude—"; and 10 (2) by adding at the end the following: 11 "(c) CONSOLIDATION OF REPORTING REQVIRE- H 12 ME.VTS.—A State may consolidate any of the reporting re- - 13 quirements of this Act that relate to ambient water quality 14 into the report required under this section.". MM . • 15 SEC. 309. SECONDARY TREATMENT. 16 (a) COASTAL DISCHARGES.—Section 304(d) (33 17 U.S.C. 1314(d)) is amended by adding at the end the fol-«•« m 18 lowing: - 19 "(6) COASTAL DISCHARGES.—For purposes of 20 this subsection, any municipal wastewater treatment MMM) ^ 21 facilin* shall be deemed the equivalent of a second- ""* 22 an' treatment facility if each of the following re- 23 quirements is met: MM* — 24 "(A) The facilitvr employ chemically en- - 25 haneed priman' treatment. fHSENT BY: LASD EXEC. OFFICE; 6-26-95 4:27PM; 310 695 8660 => 6199420677; #3/5 75 1 "(B) The facility, on the date of tin- enact- 2 ment of this paragraph, discharges through an 3 ocean outfall into an open marine environment 4 greater than 4 miles offshore into a depth 5 greater than 300 feet. 6 "(C) The facility's discharge is in eonipli- 7 ance with all local and State water quality 8 standards for the receiving waters. 9 "(D) The facility's discharge will be sub- 10 ject to an ocean monitoring program acceptable 11 to relevant Federal and State regulatory agen- 12 cies.". 13 (b) MODIFICATION OF SECONDARY TREATMENT RE- 14 Ql'IREMENTS.— 15 (!) IN GENERAL.—Section 301 (33 U.S.C. 16 1311) is amended by adding at the end the follow- 17 ing: 18 "(5) MODIFICATION OF SECONDARY TREATMENT RE- 19 Ql'IREMENTS.— 20 "(1) IN GENERAL.—The Administrator, with 21 the concurrence of the State, shall issue a 10-year 22 permit under section 402 which modifies the require- 23 ments of subsection (b)(l)(B) of this section with re- 24 spect to the discharge of any pollutant from a pub- 25 licly owned treatment works into marine waters SENT 9Y: IASD EXEC. OFFICE; 6-26-95 4:28PM; 310 695 8660 -> 6,99420677; "CID 1 which arc at least 150 feet deep through an ocean 2 outfall \vhich discharges at least 1 mile offshore, it' 3 the applicant demonstrates that— 4 "(A) there is an applicable ox-can plan and 5 the facility's discharge is in compliance with all 6 local and State water quality standards for the 7 receiving waters; 8 "(B) the facility's discharge will be subject 9 to an ocean monitoring program determined u> 10 be acceptable by relevant Federal and State- 11 regulatory agencies; 12 "(C) the applicant has an Agency approved 13 pretreatment plan in place; and 14 "(D) the applicant, at the time such modi- 15 fication becomes effective, will be disc-harping 16 effluent which has received at least chemically 17 enhanced primary treatment and achieves a 18 monthly average of 75 percent removal of sus- 19 pended solids. 20 "(2) DISCHARGE OF ANT POLLUTANT INTO M,\- 21 RIXE WATERS DEFINED.—For purposes of this sub- 22 section, the term 'discharge of any pollutant into 23 marine waters' means a discharge into deep waters 24 of the territorial sea or the waters of the contiguous 'SENT P.Y: LASD EXEC. OFFICE; 6-26-95 4:28PM; 310 695 8660 «> 6199420677; #5/5 77 1 zone, or into saline estuarine waters where there is 2 strong tidal movement. 3 "(3) DEADLINE.—On or before the 90th day 4 after the date of submittal of an application for a 5 modification under paragraph (1), the Administrator 6 shall issue to the applicant a modified permit under 7 section 402 or a written determination that the ap- 8 plication does not meet the terms and conditions of 9 this subsection. 10 "(4) EFFECT OF FAILURE TO RESPOND.—If the 11 Administrator does not respond to an application for 12 a modification under paragraph (1) on or before the 13 90th day referred to in paragraph (3). the applica- U tion shall be deemed approved and the modification 15 sought by the applicant shall be in effect for the sue- 16 ceeding 10-year period.". 17 (2) EXTENSION OF APPLICATION DEADLINE.— 18 Section 301(j) (33 U.S.C. 131 l(j)) is amended by 19 adding at the end the following: 20 4t(6) EXTENSION OF APPLICATION DEADLINE.— 21 In the 365-day period beginning on the date of the 22 enactment of this paragraph, municipalities mav* * 23 apply for a modification pursuant to subsection (s) 24 of the requirements of subsection (b)(l)(B) of this 25 section.".