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4.b - Project No. 101 - Westside Pump Station Abandonment Project Costa Mesa Sanitary District …an Independent Special District Protecting our community’s health and the environment by providing solid waste and sewer collection services. www.cmsdca.gov f To: Board of Directors Via: Scott Carroll, General Manager From: Rob Hamers, District Engineer Date: September 9 , 2013 Subject: #1 01 West Side Pumping Station Abandonment – Update on Engineer’s Estimate Summary The primary goals of the preliminary engineering stage are to confirm pipeline alignments and to prepare a preliminary engineer’s estimate in order to properly budget for the project. Attached hereto is the preliminary engineer’s estimate that will allow the District the foresight to continue yearly funding contri butions in order to abandon six Costa Mesa Sanitary District pumping stations. The preliminary engineering plans are approximately 70% comp lete. Staff Recommendation The Board of Directors discuss District Engineer’s estimate for the project. Analysis Pumping stations are constructed because residential and commercial developments are constructed in low -lying areas that are below the elevation of the nearest gravity sewer. The pumping station itself is constructed in the lowest portion of the low -lying area. Because the pumping station is in the lowest part of the low -lying area, when a gravity sewer is used to abandon the pumping station, the new gravity sewer will be extra deep as it leaves the low lying area. This is particularly the case of the pro posed gravity sewer leading from the Canyon Pumping Station to the abandonment network. Fortunately, the other five new gravity sewers will not be as deep as the Canyon sewer. The depths are as follows: Canyon 17’-36.5’; Westbluff 4.5’-11’; Aviemore 4’-7 .5’; Seabluff 9’-11’; 19 th Street 7’-17’, and President 5’-7’. Board of Directors September 9 , 2013 Page 2 of 4 Although the sewer will be extremely deep, it will serve to abandon the pumping station. Maintenance of the new, extra deep, gravity sewer is achievable with the current cleaning equipment ow ned by the District. The new gravity sewer will likely be installed by directional drilling. Abandoning a pumping station involves removing all of the equipment from inside the concrete structure, drilling multiple holes in the bottom of the structure, re moving the top 5 feet of the structure, filling the structure with sand, then restoring the surface area to match the surrounding area. Abandoning a force main involves cutting the ends of the pipe, then filling the pipe with air -blown sand cement slurry. Along with abandoning the pumping stations and force mains, the easements therefore must be vacated or quitclaimed. T he current schedule reflects OCSD’s projected construction completion date is the end of March 2019 with a start date of the end of March 2017. The current projected balance in the CMSD project account, including the 2013 -2014 contribution of $400,000, is approximately $2,069,253 (assumes 1% interest). Continued yearly contributions of $400,000 will achieve an approximate balance of $4,23 5,611 at July 1, 2018, which assumes 1% interest for the next five years. As of July 1, 2018, there should be sufficient funds to fund final design, construction, contract administration and inspection. However, a contingency budget is needed for this pr oject in the amount of $377,135. Total project costs including final design, construction, contingency, contract admi nistration, and inspection is $4,613,485 . The current annual contribution of $400,000 is not enough to cover the total project cost. An additional $65,000 a year is needed to successfully fund this project. Contract administration and inspection costs are based on a total 20 -month construction timeframe for the new District gravity sewers and pumping station abandonments. Abandoning these six pumping sta tions will save approximately $50,465 annuall y in maintenance and repair cost s . No longer will the District have to budget for preventive maintenance, pump, pipe and valve replacements and for a SCADA system. Furthermore, the District will save approximately 852 staff hours annually for routine maintenance such as transducer and wet well cleaning, exercising and cleaning check valves, testing SCADA, replacing batteries, and routine inspections . The saved staff hours can be transferred to other maintenance activities such as manhole cover inspections, pest control, equipment maintenance, etc. The District will achieve major savings by avoiding the yearly electrical costs to operate the pumping stations couple d with avoiding the capital costs for upgrading the pumpi ng stations over time along with avoiding the capital costs of having to replace or line the existing force mains. President Pumping Station was never converted to a submersible pumping station in accordance with District sta ndards because of the abandonment project. This project alone would cost $1.2 million if accomplished today. Additionally, abandoning the pumping stations saves approximately 27.5 metric tons of greenhouse gases per year. Attached is a table showi ng savin gs of approximately $15.6 million over the next 50 years assuming a relatively low interest rate of 1%. Board of Directors September 9 , 2013 Page 3 of 4 Strategic Plan Element & Goal This item complies with the objective and strategy of Strategic Plan Element 1.0, Sewer Infrastructure , which states as follows : ”Objective: Our objective is to collect and transport wastewater to meet the needs of existing and future customers. Strategy: We will do this by the careful management of the collection infrastructure using prudent planning and maintenance , with financial strategies to maintain sufficient capacity and respond to changing regulatory demands.” Legal Review This report does not necessitate District counsel review. Financial Review The Engineer’s Estimate for this project is as follows: Design: $ 160,000 Construction: $3,771,350 Contingency (10%): $ 377,135 Contract Administration: $ 125,000 Inspection: $ 180,000 TOTAL: $4,613,485 This project currently has a balance of $2,069,253 . Contin ued yearly contributions of $465 ,000 will achieve an approximate balance of $4,639,491 at July 1, 2018 , which assumes 1% interest for the next five years. When completed this project will save approximately $50,465 annuall y in maintenance and repair costs and $15.6 million in capital and electrical costs over the next 50 years along with 27.5 metric tons per year of greenhouse gases. Budget Transfer Account Account Number Increase Decrease Sewer – Project #101 Westside Pump Station 20 -200601 -4300 $65,000 Sewer – Asset Management Fund 20 -200000 -4720 $65,000 Board of Directors September 9 , 2013 Page 4 of 4 Public Notice Process Copies of this report are on file and will be included with the entire agenda packet for the September 9 , 2013 Board of Directors study session at District Headquarters and on the District website. Alternative Actions 1. The Board rec onsiders the relative high percentage of the total abandonment costs for abandoning the Canyon Pumping Station. The Board may co nsider not abandoning the station due to the high cost and the challenges in maintaining such a deep gravity sewer. The new gravity sewer will vary in depth and if constructed at a slope of 0.0040, the sewer will be less than 20 feet deep for 400 linear feet, between 20 -30 feet deep for 705 linear feet, and greater than 30 feet deep for 1,249 linear feet. The deepest point will be 36.5 feet deep. In order to lessen the depth to less than 30 feet, a slope of 0.0012 is currently under analysis. At the present time, the deepest manholes in the District are approximately 18 feet deep. 2. Direct staff to report back with more information. Attachment s A : Engineer’s Estimate s of Construction Costs B: Preliminary Engineerin g Scope of Work C: CMSD Exhibit of Sewer Lines D: Table of Estimated Capital & Energy Savings E : OCSD Email Update