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Project 129 - Study - Hamers - 2003-04-28 SpSANITiti, 311—r" Costa Mesa Sanitary District w Phone (714) 754-5043 Updated Sewer Flow Study Fax & (7144 432 1436 Cost Analysis Web Address col costa-mesa ca IS Mailing Address P 0 Box 1200 Costa Mesa, CA 92628-1200 Project #129 Bristol Street Sewer System Street Address ,QcOf ESS/o& 77 Fair Drive �Q. �\r1 B. Hktf e; Costa Mesa, 04 0, Q� �di C 92626-6520 Co RC 31720 M `z EXP 1 1'112004 * 1 * , J! C VII �Q' qlf OF C A .Pci—' Board of Directors Arlene Schafer Greg Woodside February 2003 4rt Perry James Ferryman Dan Worthington Robin B. Hamers Manager/District Engineer •A a Pr nted Recycled Pape 1. Purpose The purpose of this updated sewer flow analysis and cost estimate is to take into consideration the Costa Mesa Sanitary District (CMSD) projects that have been completed or are in design and whether these projects suggest a previously considered solution to providing adequate sewer service to the east Santa Ana Heights area is now the most cost effective solution. The successful completion of these projects changes the economic balance between the alternatives studied to provide the sewer flow capacity to adequately serve the ultimate build-out of the area. II. Background The east Santa Ana Heights area is in unincorporated Orange County and also within the boundaries of the Costa Mesa Sanitary District. As sewer provider for the area, the Sanitary District has historically reflected in its sewer master plan that the existing sewer system for the area was designed to accommodate the low density residential development that originally existed in the area. Because of increased demand for air travel and the expansion of the John Wayne Airport(JWA), the Sanitary District first went on record in 1981 that major improvements to the system were needed to serve the proposed commercial redevelopment of the area. Because the improvements were so costly and unaffordable, the District recommended to the County that the property owners benefiting from the land use change be responsible for the cost of providing the additional sewer capacity In 1983 the Sanitary District prepared the Santa Ana Heights Sewer Study that analyzed the existing and future development of the area and identified the projects needed to properly expand the system. As part of the John Wayne Airport Land Use Plan prepared for the airport expansion, the County s consultant re-studied the sewer system and made recommendations for improvements. The County sewer study performed by BSI 1 Consultants agreed with the CMSD study with respect to improvements required to expand the system. Both studies concluded that instead of expanding the existing system in place (identified as Alternative 2), it was more cost effective to construct a new pumping station at the intersection of Birch Street and Bristol Street Southbound and pump the flows across the 73 Freeway along Birch Street, to a point of connection with an Orange County Sanitation District trunk line in MacArthur Blvd(Alternative 1). A plan showing Alternative 1 is attached and labeled Exhibit A III. Status of Project The Costa Mesa Sanitary District, the City of Newport Beach, and the redevelopment arm of the County for the Santa Ana Heights area, the Orange County Development Agency(OCDA), entered into a three party agreement for design and construction of the Alternative 1 facilities. The facilities are known as the Bristol Street Pumping Station, Force Main and Gravity Sewers. The design phase was recently completed to a 90% stage, and the plans, specifications, and estimates (PS&E) are ready for approval and bidding. The estimated construction cost of Alternative 1 is shown in Exhibit 'B' and is $2.25 million. IV Change in Economic Balance Since the 1983 study identifying Alternatives 1 and 2, various projects improving the existing system have been completed or are in design. Certain facilities required rehabilitation due to age, reconstruction to provide worker safety or relocation due to road widening projects. Just recently the County notified the Sanitary District that Irvine Avenue is planned for widening, which will require relocation of the District's Tustin Pumping Station. Because the relocation can be designed to include an expanded 2 pumping station able to serve the Santa Ana Heights area in its future master plan condition, the economic balance has swung in favor of expanding the one remaining section of the District's system rather than constructing the Bristol Street Pumping Station, Force Main, and Gravity Sewers. V Improvements Required to Utilize Existing System—Revised Alternative 2 A review of each segment of the Alternative 2 facilities beginning from the downstream end is as follows. The review includes whether the existing facility is adequate or requires expansion to handle the redeveloped Santa Ana Heights areas. The results are shown as Revised Alternative 2 in Exhibit `C' and the estimated construction cost is shown in Exhibit `D' 1 Fair Drive Sewer The existing 24' sewer main has a capacity flowing full of 5 86 million gallons per day (mgd) and the projected ultimate flow is 5 41 mgd. This flow is slightly above the allowed design standard but below the capacity flowing full. This is an acceptable operating situation and no improvements are required. 2. Elden Pump Station Force Main The 18' diameter transite line that was deteriorating was replaced with 18' ductile iron pipe in two phases; Project#130 1,199 feet in 1994 and Project#135 1,093 feet in 1995 3. Elden Pump Station The original underground pumping station was built in 1956 and although considered state-of-the-art at the time, it contained two features that were considered potential significant safety hazards. The electrical controls were housed underground in a section of the pumping station that would become inundated if the station failed. Secondly access to the station was by a 20 foot vertical ladder, and a daily check of the station was 3 required. Under OSHA definitions, the station was considered a Confined Space and required a three man crew and safety apparatus to access the station. To alleviate these concerns,the District rebuilt the station in 1990 under Project#99 and convened it from a wet-well dry-well station to a submersible station. The rebuilt station and force main are sized to handle the ultimate flow from the Santa Ana Heights. 4. Tustin Force Main The existing force main consists of 580 feet of 10' ductile iron pipe built in 1969 and 2,835 feet of 14' ductile iron pipe built in 1975 There have been two breaks in the 14' force main; one in June 1996 and one in September 2001 During the second break the pipe condition was analyzed and the deterioration was indicative of additional weakened segments throughout the line. The 14' line is deteriorating from the outside because there is no polyethylene wrap around the outside of the pipe to withstand the adverse soil conditions. The pipe wall of the section removed was extremely thin and because there is concern for the remainder of the pipe, a capital replacement project was approved as part of the 2002 2003 budget. The design of Phase I of the replacement will be starting in the near future and can include sizing to accommodate the master plan flows from the Santa Ana Heights. 5. Tustin Pumping Station The Tustin Pumping Station is the CMSD facility most impacted by the flows from the east Santa Ana Heights area. The pumping station has little storage capacity and coupled with high flows there is little time to respond to a power outage or other emergency This has been an on-going concern of the District. Recently the County of Orange notified the District that Irvine Avenue will be widened. Because the pumping station is located in the parkway at the westerly corner of Irvine Avenue and Mesa Drive, the widening project impacts the station. Studies of either performing a substantial remodel or relocating the station were recently completed and it was concluded that relocating the station across Irvine Avenue is the most desired solution. As part of the relocation, the CMSD can increase the storage capacity of the 4 station to accommodate the ultimate flows from the Santa Ana Heights area. The Sanitary District budgeted $600,000 under Project #168 for the relocation. 6. Two 12" Gravity Sewers along Santa Ana Delhi Channel Attached as Exhibit `E' is an updated flow analysis of the two 12' parallel gravity sewers along the Santa Ana Delhi Flood Control Channel. To accommodate the increased flow from the east Santa Ana Heights area, the two 12' lines can be tied together The total flow into the lines of 1.56 mgd can be handled by the total capacity of 2.05 mgd. Although the total flow causes each pipe to flow at a level above design capacity each pipe will flow at an ultimate condition of less than full, which is acceptable. The tie-across is a minor construction item and the cost is included in the overall cost for Revised Alternative 2. 7 8" Sewer Line in Bristol Street Under the scenario of utilizing the existing system to handle the increased flow the existing 8' sewer in Bristol Street requires upsizing to 15' A study of Bristol Street discloses there is no available area to relocate the line, therefore, the line must be replaced in-place with the larger line. The limits of this work and the associated 12' line tie-across are shown in Revised Alternative 2 in the attached Exhibit `C' V Revised Costs to OCDA and Benefits to CMSD As shown above, the Costa Mesa Sanitary District has improved or is improving over half the existing system due to the reasons stated. These improvements have already accommodated or can easily accommodate the master plan flow Therefore, the improvement cost to the OCDA for Revised Alternative 2 for utilizing the existing system consists of upsizing the existing 8' line in Bristol Street to 15' and constructing the tie-across of the two 12' lines along the flood control channel. This compares to the previously selected Alternative 1 as follows: 5 Alt. 1 New Pump Station, Force Main & Gravity Lines $2.25 million Rev Alt. 2 Utilizing the existing system(upsizing 8' line) 0.78 million Construction Cost Saving $1 47 million The benefits to the Costa Mesa Sanitary District consist of not having to own, operate, and maintain, a sewer pump station, and not having to own and maintain an 18' gravity sewer that runs along Birch Street in the City of Newport Beach. The CMSD owns 20 pumping stations and there is a significant on-going maintenance and operation costs for each station. It is a significant benefit to the District not to own an additional station. VI. Conclusion The master plan flows from the east Santa Ana Heights area can be accommodated by either upgrading the existing system, shown as Revised Alternative 2, or constructing an entire new system redirecting the flows in a different direction, shown as Alternative 1 Due to the extended time frame of the project caused by a variety of reasons, such as the Orange County bankruptcy and design considerations with the CNB over eventual ownership of Alternative 1 facilities, approximately half of the existing system has been upgraded or will be upgraded as part of already approved projects. Therefore, it is more cost effective to upgrade the last section of the existing system rather than build the new system. The savings to the County is approximately$1.5 million and the savings to the Sanitary District is one less pumping station and no additional gravity sewer to maintain. VII. Recommendations It is recommended the OCDA, the Costa Mesa Sanitary District, and the City of Newport Beach, revise the Three Party Agreement to reflect acceptance of Revised Alternative 2 and the CMSD move forward with completing the plans, specifications, and construction. 6 _ N 1I \ N 11 ,tMrR i a. i / ,,,, , „To.. 1 , , , 164—Tragill\M • 1 , ' 1 \ /// \•N/ /a' n o / %//c,�' \ / ■ \is 11 x R-4 / 5 / \li z 4 , 'I, , // `I o / 1 \\��/ 4 ' \N) %�/ til \ % l• > C ARTHUR - LV'1 Ptf r1NG STATIO'J - -'� ! . '�' ✓ 3W . , , / �, / \ e? A trait/.q I/ s \\/' / r/ lint:CL/D/NS /NPFOYEMENTS\ I f \/N ' /N MESA DFIV \ , ♦� \ ! i /�'cfr S7:477DAB �.ro, N 1N pp \ c / N / / r,\ N a \ / 11 6� P� / S�/ �� N Z'9 I I .I OQ % 5 �. \ / • N I N. / // 't ~ / / / / ,, 1 2> ,r c÷ / . / ° \ / ■ C / 4 / / / / N / c�/ / // // � / / I / / �/ I r/ i Q / \ J -1 5} / / i , 1 / 7i i i p J/ % �!C Li Ir / / l I ss. -sr / / __ z1 , L— 4 Y4 \ / d / / I / J */ , I fV \/ t. �-�,/ SCALE /'= 600' he -,1 EXHIBIT "B" ALTERNATIVE 1 COSTA MESA SANITARY DISTRICT 234 E. 17th. St. Suite 205 Costa Mesa, CA 92627 (949) 548-1192 COST & QUANTITY ESTIMATE PROJECT CMSD PROJECT NO. 1112100-129 NO. IIITEM IIQUANTITY UNIT PRICE ICOST 1 1 18"VCP SEWER 3726 I.f. $250.00 $931,500.00 1.2 12"VCP SEWER 41 It $175.00 $7,175.00 1.3 60"SEWER MANHOLE 10 ea. $3,500.00 $35,000.00 1.4 REMOVE CONFLICTING PORTION OF EXIST. 12" FORCE MAIN 132 I.f. $75.00 $9,900.00 1.5 CONNECT EXIST 12"OCSD SEWER FORCE MAIN TO NEW Mi 1 ea. $4,000.00 $4,000.00 1.6 JOIN EXIST. SEWER MANHOLE& RECHANNEL BASE 1 ea. $4,000.00 $4,000.00 1.9 REMOVE SEWER CLEANOUT&JOIN EXIST. SEWER FORCE h 1 ea. $1,200.00 $1,200.00 1.12 POT-HOLE EXIST. STORM DRAIN 3 ea. $500.00 $1,500.00 1.14 POT-HOLE EXIST. WATER MAIN 2 ea. $500.00 $1,000.00 1.15 CUT, PLUG &ABANDON EXIST 8"VCP SEWER 1 I.s. $1,000.00 $1,000.00 1 16 INSTALL WYE&JOIN EXIST. SEWER LATERAL 26 ea. $1,500.00 $39,000.00 1.17 REMOVE EXIST. SEWER MANHOLE&FILL W/SAND CEMENT 12 ea. $500.00 $6,000.00 1 18 SEWER CLEANOUT 27 ea. $300.00 $8,100.00 1 19 18" RCP STORM DRAIN 40 I.f. $225.00 $9,000.00 1.20 21" RCP STORM DRAIN 35 It $250.00 $8,750.00 1.21 RCP COLLAR 4 ea. $750.00 $3,000.00 1.22 8"VCP SEWER 17 I.f. $160.00 $2,720.00 1.23 48"SEWER MANHOLE 1 ea. $3,000.00 $3,000.00 1.24 COAT SEWER MANHOLE 1 ea. $500.00 $500.00 2.1 200mm (8") DIA.YELLOWMINE SEWER PIPE 71 I.f. $175.00 $12,425.00 2.2 200mm (8") DIA.YELLOWMINE FITTING AND CONST. THRUST 2 ea. $350.00 $700.00 3A PUMP STATION,VALVE VAULT AND APPURTENANCES 1 I.s. $525,000.00 $525,000.00 3B OVERFLOWVAULT AND APPURTENANCES 1 I.s. $65,000.00 $65,000.00 3C DRIVEWAY PER CALTRANS (W=34', X=3') 2 ea. $2,000.00 $4,000.00 3D 6" PCC SIDEWALK 4675 s.f. $5.00 $23,375.00 3E 6" PCC CURB 295 I.f. $15.00 $4,425.00 3F ELECTRICAL&ODOR CONTROL PANEL 1 I.s. $35,000.00 $35,000.00 3G CHAIN LINK FENCE 235 I.f. $10.00 $2,350.00 311 5'WIDE CHAIN LINK FENCE GATE 2 ea. $300.00 $600.00 4.1 12"VCP SEWER 696 If $350.00 $243,600.00 4.2 SEWER MANHOLE 1 ea. $5,000.00 $5,000.00 4.3 COAT SEWER MANHOLE 4 ea. $600.00 $2,400.00 4 4 DROP STRUCTURE/JUNCTION W/PUMP STATION 1 I.s. $1,500.00 $1,500.00 4.5 REMOVE INTERFERING PORTION OF EXIST 8"VCP SEWER 657 It $50.00 $32,850.00 4.6 8"VCP SEWER OVERFLOW BYPASS 1 ea. $500.00 $500.00 4.7 RECHANNEL EXIST. MANHOLE BASE 3 ea. $1,000.00 $3,000.00 4.8 - PROTECT IN PLACE ALL TRAFFIC SIGNAL LOOPS 1 I.s. $3,000.00 $3,000.00 4.9 INSTALL WYE&JOIN EXIST 6 SEWER LATERAL 4 ea. $400.00 $1,600.00 4.10 DROP STRUCTURE 1 ea. $1,000.00 $1,000.00 10%CONTINGENCY $206,330.00 TOTAL $2,250,000.00 1 Co ® 't _r .0 , T � !: t,, �+a "�„s ?�.J •4.. iii - , x1 r; 9 *. . ` r..F.• V `L., E r`_ FiE J L 7• ti 0 o 0 f• { • •=• k _ R/YIRS/0 • ,4 • 1 j • • • • A/EAS/D6. I i : / •.\°-V b W ".y , oa.�• a e PO Q • b� ® •r , I r ii.. Y!R A. 4 i- .a. - i z J 12.111-1t4 1,• A CA C/A a.m.\ - • > _ • . •_ �._• a • � _ I :�\• — Sr 1 i 1 k I O •,... .• CYPRESS • ST • v e • h • II 2 [ i �� .AVE. I �/ ' BAY V/EW i CS oacfroo sr owl , ...==. i • Li. .;... , Y:1_ !fk t II ti • • Slag.0=•—_• •J I SCHOOL.•:::irlit•■•••■•0 i L Mr cw Q - ..;,: AVE Y view • • HAn/NAL M / _ I .11. ': f - - EXHIBIT "D" REVISED ALTERNATIVE 2 COSTA MESA SANITARY DISTRICT 234 E. 17th. St. Suite 205 Costa Mesa, CA 92627 (949) 548-1192 COST & QUANTITY ESTIMATE PROJECT BRISTOL ST SEWER SYSTEM NO ITEM HQUANTITY IUNIT PRICE (COST 1 REMOVE EXIST. 8" SEWER&CONSTRUCT NEW 15"VCP SE 2140 I.f. $300.00 $642,000.00 2 SEWER MANHOLE 9 ea. $3,500.00 $31,500.00 3 RECONNECT EXIST. 2- 12" SEWER LINES 1 I.s. $10,000.00 $10,000.00 4 5 6 7 8 CONTINGENCY 15% $101,000.00 TOTAL $784,500.00 EXHIBIT "E" FLOW STUDY & HYDRAULIC ANALYSIS REVISED ALTERNATIVE 2 The purpose of this study is to revisit Alternative 2 of the Santa Ana Heights Sewer Study (Project No. 109), which identifies improvements necessary to the existing system in order for it to handle the ultimate flow A. BRISTOL STREET SEWER A new replacement sewer in Bristol St. from Cypress to the existing siphon under the Santa Ana Delhi Channel would need to be constructed to relive the overburdened existing 8' main. Per BSI Report the ultimate flow for this reach is 1 123 cfs. Q=k/nD^(8/3)S^0.5 where n=0.013 k=0.232 for pipe flowing 'A full, S(exist)s 0.0024 Qult.=1 123 cfs, then D=((1 123x0.013/0.232)/0.0024^0.5)^0.375=1.09'=13.2' New minimum 15" pipe is required B. TWO 12" SANTA ANA DELHI CHANNEL SEWERS Revised Flow Study from 12/17/86 Areas 1 and 3 consist of 44.9 ac. of low density residential, 13.3 ac. of medium density residential. Average flow Qave.44.9x1545gpd+13.3x2525gpd=0.103 mgd Peak Flow Qpeak=1.82xQave^0.92=0.227 mgd Storm Flow Qst.(44.9+13.3)x800gpd=0.047 mgd Qtotal=0.274 mgd=0.425 cfs Area 2- sewer line northerly of OCFCD channel and westerly of Bristol St. siphon Total flow of 0.56 mgd=0.868 cfs has not changed from original 12/17/86 sewer study Line B- Santa Ana Heights Area From BSI Report(03/15/90) total flow Qb=1.123 cfs Total flow at the siphon on Bristol St. Qt=0.425+0.868+1 123=2.416 cfs There are 2 12' pipes along Irvine Ave. south of the siphon. The slope of existing 12' sewer lines S=0.0020 Then capacity of 12' pipe flowing full Qir'i ii=0.463/nD^(8/3)S^0.5 n=0.013, D 1 S=0.0020 Q1z^fuu=0.463/0.013(0.002)^0.5=1.59 cfs. Qin n,r1.59/2=0.80 cfs From King's Hydrology Manual, k=0.351 for Q=Qt/2=2.416/2=1.208 cfs, Then D(depth of flow)/d(diameter of pipe)=0.65, and D=0.65 Field Check of Current Operating Condition: Easterly 12' sewer D=4.5' (12/19/02) Westerly 12' sewer D=2.5' (12/19/02) Bristol Street 8' sewer D= ( )