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HomeMy WebLinkAbout; ; Encina Water Pollution Control Facility Joint Advisory Committee ENCINA PLANT EXPANSION FINAL DESIGN REPORT; 1973-09-18n J l r 'l ' ' II rl lI I! 'f f u u LI ENCINA WATER POLLUTION CONTROL FACILITY JOINT ADVISORY COMMITTEE ENCINA PLANT EXPANSION FINAL DESIGN REPORT 1973 September 18, 1973 Prepared pursuant to JAC's Request of August 22, 1973 NESTE, BRUDIN & STONE INCORPORATED Engineers ENGINEERING-SCIENCE, INCORPORATED Engineers for the for the SAN MARCOS COUN'I'Y WATER DISTRICT LEUCADIA COUNTY WATER DISTRICT n • i fl ' ; r f1 ! I ,i A !l II Il 11 T ' u u u Li u l .· 2. 3. 4. 5. TABLE OF CONTENTS CHAPTER Scope of Work Design of Enlargement Table 2-1 -Design Criteria for Phase 2-A Expansion Schedule of Work Calendar of Events Cost Estimate Table 4-1 -Estimated Phase Construction Cost Preliminary Financial Plan i PAGE 1 3 6 7 8 10 11 12 !1 fl ' I 4 l ,, I ' . !I II Il II '' ,J ' ' iJ ' ' u , f u Ll u CHAPTER l SCOPE OF WORK At the request of the San Marcos County Water District and the Leucadia County Water District a preliminary report was prepared covering a possible 3.0 MGD enlargement of the Encina Water Pol- lution Control Facility (WPCF). This report was prepared on the assumption that these two agencies were the only entities desiring to implement an immediate expansion of the plant, to be performed concurrently with the construction presently underway, known as the Phase 2 expansion. Phase 2 increases plant capacity from 6.75 MGD to 9.75 MGD. The Phase 2-A proposal would have increased the total plant capacity to 12.75 MGD. The preliminary report for Phase 2-A was presented to the Joint Advisory Committee (JAC) meeting of August 15, 1973. In the ensuing discussion, it became apparent that the cities of Carlsbad and Vista also wished to secure additional capacity at this time, indicating that the incremental expansion might be more than 3.0 MGD. A committee was appointed to review this concept with the staffs of the Regional Water Quality Control Board and the Regional Coast Commission and to report back at the special meeting on August 22, 1973. The results of these staff meetings indicated that the 3.0 MGD was not a controlling factor in considering a Phase 2-A expansion. 1 n •• • f' • • '' " . 'l ' i II II Il Il II ' ' i.J T ' iJ T r u ' f u u Li Accordingly, the JAC committee requested that the consultants (Neste, Brudin & Stone Incorporated and Engineering-Science, Inc.) preparing the Phase 2-A report enlarge the scope of their study to determine the feasibility of increasing the size of the en- largement to 4.0 MGD, with the capacity allocation to be shared by each of the four participating agencies, City of Carlsbad, Vista Sanitation District, San Marcos County Water District and Leucadia County Water District. This report, incorporating the results of a preliminary review of .the potential for increasing the scope of the enlargement to conform to this request, was presented on August 29, 1973. Accordingly, the City of Carlsbad, Vista Sanitation District, San Marcos County Water District and the Leucadia County Water District decided to each share a 4.0 MGD expansion equally. It was decided to finalize this arrangement with a Sixth Supplement to the Basic Agreement and that agreement now under discussion. 2 r l ' • • fl ' . fl " ' ,, ' • i II Il II Ll ' ' u l ' u u BACKGROUND CHAPTER 2 DESIGN OF ENLARGEMENT Currently the Encina Water Pollution Control Facility is under- going expansion. This expansion program (Phase 2, 1973) will increase the plant's treatment capacity from 6.75 MGD to 9.75 MGD. At the completion of the Phase 2 expansion program, the City of Carlsbad will own a 3.47 MGD share, Vista Sanitation District will own a 3.05 MGD share, San Marcos County Water District will own a 1.40 MGD share and the Leucadia County Water District will own a 1.25 MGD share of the capacity rights. These shares are inadequate to meet the existing and proposed treatment commitments of the four agencies. The current rapid growth experienced by all of these agencies indicates the need for capacities in excess of those allocated under Phase 2 even before the construction of this phase has been completed. How- ever, there is apparently no way that any increase can be accom- plished while the contractor is occupying the site for the Phase 2 construction, other than by an arrangement with the same con- tractor to increase the scope of his work. Discussion with this contractor indicates that it would be possible to accomplish such an increased scope of work, provided that they know definitely before they have proceeded into Phase 2 too far to incorporate 3 ,, • I l • • • n a • '' ' j, !1 Il Il II T ' lJ Ll ' p ' u Ll l r u the changes into the construction. The contractor has advised that the last date for making such a decision is September 19, 1973. To meet existing and proposed treatment needs through 1976, the four agencies will need a total of at least 4 MGD additional treatment and disposal capacity. A review of the facilities as they will exist when Phase 2 is complete indicates that the desired increased capacity could be attained by incorporating the following added facilities: Type of Improvement(a) 1. Primary Sedimentation Tank 2. Air Operated Primary Sludge Valve 3. Primary Scum Pump & System 4. Digester Boiler 5. Mechanically cleaned Bar Screen (20 MGD Capacity) Additional Units Required 1 1 1 1 1 Based on process and hydraulic review and discussions with the San Diego County Department of Sanitation and Flood Control and on data from the Phase 2 design engineers, the balance of the Encina Water Pollution Control Facility, including plant and land/ocean outfall system, will be capable of handling a 4 MGD incremental flow increase with no additional modifications at this time. (a) Selection of actual equipment and verification of details as to location and conformance with existing processes to be made prior to final design. 4 '1 ' 1 n i . n 1 ' n ' ~I !l II Il II ' ' lJ ' ' iJ u DESIGN CRITERIA A review of available information indicates that the present primary sedimentation basins have a capacity of 2.5 MGD each when operated at a surface overflow rate of 780 gpd/ft2 , at a detention time of 2.0 hours. The Phase 2-A plan is flexible to the extent that it can be sized for a 4.0 MGD incremental increase needed to accommodate the desires of those member agencies in need of immediate expansion. Preliminary design criteria for the pro- posed additions are summarized in Table 2-1. Based on available capacity after Phase 2 expansion, no additional expansion to the land and ocean outfall system will be required. 5 n l • fl l • • " l • ,, ' 1 !I Il Il II l' j 1 ' u Ll u TABLE 2-1 DESIGN CRITERIA FOR PHASE 2-A EXPANSION FLOW (MGD) Average Dry Weather Peak Dry Weather Peak Wet Weather PRIMARY SEDIMENTATION TANKS Number Size (feet) Overflow Rate (gpd/ft2) ADWF PWWF Detention Time (hours) ADWF SCUM PUMP Number Capacity (gpm) at 60' TOH Horsepower DIGESTER BOILER Number Size (BTU/Hour) BAR SCREEN Number Capacity 6 4 MGD INCREMENT 13.75 21.1 34.8 1 Add. 20W X 160L x 9SWD 860 2175 1.9 1 Add. 15 1.5 1 Add. 1,000,000 1 Add. 20 MGD n ' . n ' ' n ,, ' . II Il II f T lJ T ' u CONSTRUCTION SCHEDULE CHAPTER 3 SCHEDULE OF WORK It is estimated that final design of the Phase 2-A Interim Ex- pansion can be completed by September 28, 1973. Construction completion is contingent upon coordination with the existing Phase 2 expansion program. Preliminary estimates for construction completion define an early complete date as July 1974, and a late complete date as October 1974. Early completion of final design is important in order that the additional items of work can be scheduled into the existing construction program, taking maximum advantage of like items of construction activity, thereby minimizing duplication of con- struction effort and cost. For this reason, authorization to proceed with final design should be given at the earliest possible date. CALENDAR OF EVENTS A calendar of events critical to the implementation of the Phase 2-A Interim Expansion Program has been prepared to aid in coordi- nating the efforts of the various entities involved in this project. The project is proceeding on schedule. 7 '1 ' I. n n r1 " . CALENDAR OF EVENTS PHASE 2-A EXPANSION PROGRAM ENCINA WATER POLLUTION CONTROL FACILITY 1. File for Waste Discharge Requirements with the California Regional Water Quality Control Board, San Diego Region 2. File for Coastal Permit with Coastal f1 Commission I .& • ,, 4 ' II Il II ' ' ' &.• ' " u ' r u Ll u 3. Legal Opinion 4. Agreement between Districts and Agree- ment for Engineering Services - initiate design Leucadia CWD San Marcos CWD 5. Meeting with San Diego County Department of Sanitation & Flood Control, and Brown and Caldwell 6. Financial Plan -Buy-in capacity of ad- ditional units Preliminary Final 7. JAC Meeting 8. Preliminary Design Report -Draft Final 9. JAC Meeting 10. JAC Meeting 11. Meeting with Brown & Caldwell 12. JAC Meeting 13. Draft EIR -Adopt by SMCWD 14. JAC Approval of Phase 2-A Expansion Plan 15. Coastal Commission Hearing 16. EPA Ocean Discharge Permit 17. Design Completion 8 July 3, 1973 July 3, 1973 July 30, 1973 July 30, 1973 August 6, 1973 August 2, 1973 August 15, 1973 As Required August 15, 1973 August 15, 1973 As Required August 22, 1973 August 29, 1973 September 6, 1973 September 12, 1973 September 17, 1973 September 19, 1973 September 21, 1973 September 21, 1973 September 28, 1973 n I ' n i I, n 'l • j ,, ' i !I Il r1 II ' ., u L u 18. Receive Waste Discharge Requirements Tentative 19. Final Construction Cost Estimate 20. Final EIR -Adopt by SMCWD 21. Construction Completion -Early -Late 9 To Be Determined October 8, 1973 October 16, 1973 July 1974 October 1974 ,, ' i ' . n • J ,, • l Il II Il ll ll 11 ll , ' u u Ll u CHAPTER 4 COST ESTIMATE The preliminary construction cost estimate for the proposed Interim Expansion Program as outlined in Chapter 2 is $385,000.00. This cost estimate was prepared by Weardco Construction Corpo- ration prior to completion of preliminary plans. The costs have been reviewed and modified by the Engineer to reflect the added costs of preliminary design details. Due to the atypical nature of the design effort, an accurate estimate of the engineering design costs cannot be made. However, it is estimated that total project cost will be approximately $500,000.00 for the 4 MGD increment, all as summarized in Table 4-1. Upon design completion and JAC approval it is contemplated that the SMCWD will negotiate a contract with Weardco, Inc. for the Phase 2-A construction. This action will provide the additional Phase 2-A capacity at the completion of the present Phase 2 construction, estimated between July and October of 1974. 10 n l • ' . ,, ' i Il Il Il II lI ll il ' ' lJ u Ll Li u TABLE 4-1 ESTIMATED PHASE CONSTRUCTION COST ITEM 1. Mechanical Bar Screen 2. Pre-aeration Blowers 3. Chlorination 4. Grit Removal Tanks 5. Screen, Blower & c12 Building 6. Primary Sedimentation Tanks 7. Effluent Metering 8. Foul Air Handling 9. Solids Handling Building 10. Piping & Conduits 11. Electrical 12. Instrumentation 13. Site Work & Demolition 14. Painting 15. Flood Protection Sub-Total 16. Engineering, Contingencies, Legal, etc. (30%) TOTAL 11 Phase 2-A 4.0 INCREMENT $ 50,000 3,000 205,000 10,000 40,000 60,000 10,000 5,000 2,000 $ 385,000 115,000 $ 500,000 n n n n n r1 r1 r1 11 [) 11 [] CHAPTER 5 FINANCIAL PLAN A proposed method of computing cost to permit Vista Sanitation District, City of Carlsbad, San Marcos County Water District and Leucadia County Water District to obtain additional capacity rights in the Encina Water Pollution Control Facility (Phase IIA). Additional Capacity Rights Needed Existing Needed Total 1. Vista Sanitation District 3.05 MGD 1.00 MGD 4.05 MGD 2. City of Carlsbad 2 .43 MGD 1.00 MGD 3 .43 MGD 3. San Marcos County Water District 1.40 MGD 1.00 MGD 2.40 MGD 4. Leucadia County Water District 1.25 MGD 1.00 MGD 2.25 MGD 5. Encina WPCF 9.75 MGD 4. 0 MGD 13 • 7 5 MGD Assumptions and Criteria (1) Engineering News Record Construction Index for the Los Angeles area U used for past, present and future valuations. LI u u u u u (2) Original bid construction date April, 1964, ENR=lOOO. (3) Facilities first used September, 1965, basis for depreciation. (4) Equipment depreciated over a 20-year life. (5) Pipe and Structures depreciated over a 40-year life. (6) Phase I bids received September, 1970, ENR=l440. (7) Phase II bids received May, 1973, ENR=l950. (8) Phase II to be completed July, 1974. (9) All valuations projected to September, 1973, ENR=2175. n n n n n n n [] [) n (] ll lJ u u u u u u Original Encina Facility (1) Basic Value Plant Site and Condemnation Access Road, Power Pole Reloc., Appraisal Mi.sc. Improvements & Capital Purch. Portion of Engineering Cost Capital Improvements Junction Structure Primary Sludge P~mp Primary Digester Secondary Digester Control Building Drainage Site Grading Yard Piping Fence, Landscape, Roads Electrical (2) Depreciation (September 1965 to September 1973) 8 years Equipment Sludge Pump Facilities Control Building Electrical $ 10,000 s,ooo 10,000 $ 25,000 $25,000 X 8/20 = $10,000 Remainder 485,000 x 8/40 = $97,000 Sub-Total $107,000 $240,000 10,000 12,000 60,000 8,050 25,000 54,800 59,500 59,700 8,500 37,000 90,000 45,900 40,000 $750,000 n· n n n n n n r1 [] [] (] [) [1 ' u u u u u u Project to 1973 Value 2175 ENR lOOO = 2.175 x 107,000 (3) Inflation (not including -land) (1000 to 2175) (750,000 • 240,000) X 11,.5% (4) Summary Basic Value Depreciation Inflation Plus land appreciation Phase I Expansion $750,000 -232,700 +600,000 ' $1,117,300 89,000 $1,206,300 (1) Basic Valu.e (September 1970 to September 1973) Capital Improvements, Engineer, Administration (2) Depreciation Equipment 8500 x 3/20 = Remainder 103,000 x 3/40 = Sub-Total Project to 1973 value 2175 ENR 1440 • 1.5 x $9,000 (3) Inflation (1440 to 1950) 188,000 X 50% (4) Summary Basic Value Depreciation Inflation $ 1,300 7,700 $ 9,000 $188,000 13,500 + 94,000 $ 268,500 $232,700 $600,000 $ 188,000 $ 13,500 $ 94,000 n n n n n n fl [] Il □ [] ll ll u u u u u U· Phase II Expansion (1) Basic Value Capital Improvement Engr., Legal, Admin. Less Meter (2) Depreciation (3) Inflation (4) Summary Basic Value Depreciation Inflation Total Plant Value (1) Original (2) Phase I (3) Phase II Total Cost Sharing Agency Carlsbad Percentage Phase II San Marcos CWD Leucadia CWD 24.92 14.36 12.82 $685,300 · -10,000 $ 675,300 -o- -0- $675,300 -0- -0- $675,300 $1,206,300 268,500 675,300 $2,150,100 Ownership Phase IIA 24.95 17.45 16.36 Carlsbad San Marcos Leucadia + . 0003 X 2, 150, 100 = 645 + .0309 X 2,150,100 = 66,438 + .0354 X 2,150, 100 = 76,113 Total $143,196 Percentage Change in Ownership .03 3.09 3.54 n n n r1 n !l r1 [] n n 11 11 LI u u u u u Allocation of Agency Vista Buena Encinitas Summary Agency Vista Carlsbad Buena San Marcos Leucadia Encinitas Buy-in Cost Buy-in Paid by Carlsbad $177 $180 $288 $645 Phase IIA Cost $125,000 125,000 -0- 125,000 125,000 -0- $500,000 to Owners Buy-in Paid by San Marcos $18,158 $18,456 $29,824 $66,438 Buy-in Returned + $ 39,136 -o- + 39,780 -o- -0- + 64,280 $143,196 Buy-in Paid by Leucadia Buy-in Total $20,801 $39, 136 $21,144 $39,780 $34, 168 $64,280 $76,113 $143,196 Buy-in Net Cost (-) Cost or Refund (+) -o-(-) $ 85,864 + 645 (-) 125,645 -o-(+) 39,780 + 66,438 (-) 191,438 + 76,113 (-) 201, 113 -o-(+) 64,280 $143,196 $500,000