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11 - Assessing Force Mains Protecting our community's health and the environment by providing solid waste and sewer collection services. www.cmsdca.gov Costa Mesa Sanitary District ….an Independent Special District Memorandum T o: Operations Committee From: Scott Carroll , General Manager Date: November 13 , 2012 Subject: Assessing Force Mains Summary After the su ccess of the PICA technology on 23 rd and Santa Ana force mains , staff began to analyze the re maining 18 force mains to de termine which ones would be ideal candidates for the PICA technology. Staff Recommendation That the Operations Commit tee recommends the Board of Directors approves the proposed plan for assessing force mains and approves a budget adjustment of $176,185 to perform the PICA analysis at Harbor, Mendoza, Victoria and South Coast Plaza Pumping Stations. Analysis Of the 20 force mains withi n the Costa Mesa Sanitary District, two of them have been rehabilitated (Canyon & Irvine) and improvements for two more are currently underway (23 rd & Santa Ana). Staff noticed that these four force mains had some common features. For instance, all exper ience large volumes of waste water as demonstrated below: • 23 rd 550 gallons per minute • Canyon 800 gallons per minute • Santa Ana 1,520 gallons per minute • Irvine 1,500 gallon per minute Operations Committee November 13 , 201 2 Page 2 of 4 Also, the age of the four force mains ranged from the oldest 43 yea rs (portion of Irvine) to 28 years of age (23 rd ). The gallons per minute (GPM) and age of these four force mains is the benchmark used to evaluate the remaining force mains. Staff evaluated force mains that collected more than 550 GPM and are older than 28 years. As a result, staff believes the following force mains should be assessed by PICA. 1. Harbor 1,660 GPM 56 years of age 2. Mendoza 830 GPM 49 years of age 3. Victoria 785 GPM 38 years of age The cost to perform the PICA technology at 23 rd and Santa Ana t hat i ncludes pigging the force mains was $119,000. A total of 1,386 feet was assessed , which cost $85.86 per foot. The total feet for the force mains mentioned above is approximately 1,582 . By using the cost per foot at 23 rd and Santa Ana, staff believe s the PICA cost for the four force mains will cost the District $135,830 . You will notice in the attached spreadsheet (Attachment A) that South Coast Plaza (SCP) is cl ose to meeting the benchmark for GPM (450) and does meet the benchma rk for age (46 yea rs). Staff recommends including SCP with the three force mains mentioned above for an additional estimated cost of $40,354 . The total to PICA to four force mains is $176,185 . You will also notice that the President force main meets the benchmark. Howev er, the pump station for this force main is scheduled to be abandoned in five years . Instead of using the PICA technology, staff is recommending pot -holing several locations of the pipe and then borrowing a meter from the Orange County Sanitation District (OCSD) to determine the pipe wall thickness and corrosion. This method was used to assess the Canyon force main in which a portion of the pipe needed rehabilitation. The cost to pot -hole several loc ations are minimal and there is no cost for borrowing a meter from OCSD. The cost to rehabilitate 23 rd and Santa Ana is estimated at $753,391 , which includes a 10% contingency and contract administration and inspection services. The cost per square foot is estimated at $543.57 . If PICA reports back sever e loss of wall thickness and corrosion in all four force mains mentioned above , the cost to rehabilitate 1,582 feet of pipeline will be approximately $859,928 . If you include SCP and President, the cost could be an additional $502,908 , which will bring th e total cost to rehabilitate six force mains to $1,362,835 . There is another six force mains that do not meet the benchmark and can be assessed in future years. Those force mains, along with the assessment year s and PICA costs are identified below. The PICA cost s includes inflation (3% a year) Operations Committee November 13 , 201 2 Page 3 of 4 Assessment Year PICA Cost 1. Elden 2019 $347,414 2. 21 st 2019 $ 44,084 3. Adams 2024 $295,022 4. California 2025 $ 6,935 5. Corp Yard 2085 $ 40,857 6. Gisler 2018 $118,925 If, at the time the forc e mains above are assessed and found significant loss of wall thickness and corrosion, staff believe s the following costs will be needed to rehabilitate the force mains. The cost below includes contingency, contract administration, inspection and inflatio n at 3% per year. Construction PICA Total 1. Elden $2,199,439 + $347,414 = $2,546,853 2. 21 st $ 275,166 + $ 44,084 = $ 319,250 3. Adams $1,867,752 + $295,022 = $2,162,774 4. California $ 43,904 + $ 6,935 = $ 50,839 5. Corp Yard $ 285,664 + $ 40,857 = $ 326,521 6. Gisler $ 752,899 + $118,925 = $ 871,824 The Iowa force main cannot be assessed using the PICA technology because the pipe is made of asbestos cement pipe (ACP). PICA technology can only be used in meta l pipes such as ductile iron pipe (DIP) or cast iron pipe (CIP). Staff recommends pot -holing Iowa force main by 2041. If, at that time it is determined the Iowa force main has significant loss of wall thickness than the cost to repair this pipe in 2041 i s $290,265 . There are several force mains that is not recommended for any type of assessment because the force mains identified below are scheduled for abandon in five years. In addition, these force mains have low flow. 1. 19 th 2. Sea Bluff 3. West Bluff Av iemore Terrace (Valley) is scheduled for abandonment in five years as well, but because the flow is nearly 200 GPM and is 53 years old, staff recommends pot -holing this force main. The pipe is only 130 feet lon g, so any improvements could cost as low as $2,271 for ten feet of improvements to $29,532 for slip lining the entire line. How does the force main schedule above impact the asset management plan? Operations Committee November 13 , 201 2 Page 4 of 4 Staff conducted an analysis of the asset management plan for the next twel ve years that takes into con sideration other asset repair and/or replacement p rojects. Attachment B is the analysis that shows there will be adequate funding in the asset management to perform the force main assessment and repairs project Strategic Plan Element & Goal This item co mplies wi th the Strategic Element 1 .0, Sewer Infrastructure and Strategic Goal s No. 1 .4, System Wide Sewer Replacement and Repair Program and No. 1.6, Evaluate force main conditions on a regular basis . Legal Review Not applicable Financial Review The cos t to assess and rehabilitate force mains in the n ext twelve years years is estimated to be $7,490,560 (excluding cost to assess and rehabilitate Corp Yard , Valley and Iowa force mains). In addition, staff anticipates spending another $13,660,232 on other sewer assets. Staff anticipates that the District will be spending over $21 million in the next twelve years on sewer assets. There will be adequate money in the asset management to fund these projects. Approval of a budget adjustment in the amount of $176,185 is necessary to perform the PICA analysis. The funds will be transferred from the Asset Management Fund. Public Notice Process Copies of this report are on file and will be included with the entire agenda packet for the November 13 , 2012 Operatio ns Committee meeting at District Headquarters and on District’s website. Alternative Actions 1. Do not approve recommending the proposed plan to the Board of Directors and direct staff to report back with additional information. Reviewed by: Teresa Gonz alez Accounting Manager Attachment s A: Pump Station & Force Main Specifications B: Asset Management Analysis