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HomeMy WebLinkAbout2001 03_OPWA_Water Master Plan _Authority Policy for Extension_Expansion_Development of Municipal Water System_2001.02.20 OW ASSO PUBLIC WORKS AUTHORITY 2001-03 OPW A RESOLUTION NO A RESOLUTION ADOPTING THE WATER MASTER PLAN AS A STATEMENT OF THE AUTHORITY'S POLICY FOR THE EXTENSION, EXPANSION AND DEVELOPMENT OF THE CITY OF OW ASSO MUNICIPAL WATER SYSTEM. III is one of the fastest growing communities Oklahoma the City of Owasso WHEREAS, the state; and, of stress on the infrastructure WHEREAS, the impact of that growth places a great deal of the city, specifically on the water system; and, directly will today of infrastructure WHEREAS, proper planning and development impact growth development tomorrow; and, Authority to be proactive rather Works WHEREAS, it is the policy of the Owasso Public than reactive in matters of growth and development; and, to 1999 16 on November awarded a contract WHEREAS, Montgomery Watson was develop a water system master plan; and, has now been completed; and, WHEREAS, the Trustees of the Owasso Public Works Authority, Owasso, Oklahoma have reviewed the 2001 Water Master Plan as developed by Montgomery Watson and desire to adopt the plan as a policy statement for the development, expansion and extension of publicly financed improvements to the municipal water system of the City of Ow as so master plan, dated February 2001, a water WHEREAS, NOW THEREFORE, BE IT RESOL VED BY THE TRUSTEES OF THE OW ASSO PUBLIC WORKS AUTHORITY, OW ASSO, OKLAHOMA that the Trustees of the Owasso Public Works Authority hereby adopt the 2001 Water Master Plan as a policy statement for the Authority. of the by the Trustees PASSED AND APPROVED this 20th day of February, 2001, Owasso Public Works Authority, Owasso, Oklahoma. "'~, " HC 1,,'1""'1' \C \I\l 0 "'''ft ,,~.ee.e.e. ....... ...::::; 0 e ..<1'-- Q. :" * e..'u-_ ...0: 0.-:;"-: ::: (/). Sll f\L .- 0 :: ~ cf) . J,;.. r~ . ~ :,A.. ::::0 _ --1: e . - ";. '7'0 o. ill: .0 ..::' ? Os $G \ ....oI>"'d', O'::;L* >$ I) $ e ~ /, . '" ' ""''''01,111 ( '- Authority Secretary ATTEST MEMORANDUM HONORABLE CHAIR AND TRUSTEES OW ASSO PUBLIC WORKS AUTHORITY TO F. ROBERT CARR, JR., P.E. PUBLIC WORKS DIRECTOR FROM RESOLUTION ADOPTING WATER MASTER PLAN (OPWA RESOLUTION NO. 2001-03) SUBJECT 15,2001 February DATE BACKGROUND On November 16, 1999, the Trustees approved an Agreement for Engineering Design Service for Water System Master Planning with the engineering consulting firm of Montgomery-Watson An amendment to the original contract was approved on May 2, 2000. The final plan, which incorporated comments from the Trustees and staff, was completed on February 9, 2001. The plan provides an evaluation of the existing water distribution system to adequately provide water under present daily and peak flow demands and includes projections for the years 2005, 2010 and 2020. The evaluation determines the suitability of the water sources, pipelines, storage tanks, pumps and control valves to provide adequate pressures and flows Prime components of the plan are water demand projections based on defined land uses and development of a capital improvements plan to meet the system needs. Attached is the Executive Summary of the plan that discusses work items and findings serve as a policy statement for the development, expansion and financed improvements to the City of Owasso water serves to establish direction by determining present and future RESOLUTION: The Water Master Plan can extension of publicly or privately distribution system. Such a plan system needs. Therefore, it is proposed that the plan be adopted by resolution by the Trustees A copy of o PW A Resolution No. 2001-03 adopting the 2001 Water Master Plan as a statement of policy for the extension, expansion and development of the City of Owasso municipal water system is attached .. Page 2 OPW A Resolution No. 2001-03 of OPWA Resolution No. 2001-03 adopting the 2001 expansion and development of the the extension RECOMMENDATION Staff recommends the Trustees approval Water Master Plan as a statement of policy for City of Owasso municipal water system by Montgomery 2001) (F ebruary Master Plan Water ATTACHMENTS Executive Watson OPW A Resolution No. 2001-03 2001 Summary - 1 2 EXECUTIVE SUMMARY BACKGROUND The City of Owasso has a population of approximately 18,000 people. The City obtains water solely from the City of Tulsa. Owasso has experienced rapid growth over the past ten years and will most likely continue to experience continued strong growth over the next 20 years. The City requisitioned this Master Plan to provide recommendations for developing the necessary facilities to supply water to City customers through the year 2020 The objective of this Water System Master Plan is to provide the Owasso Public Works Department with an evaluation of the existing water system's ability to adequately provide water under existing conditions as well as to the year 2020. This evaluation will determine the suitability of the existing water sources, pipelines, storage tanks, pumps, and control valves to provide adequate pressures and flows under both existing and 2020 conditions PROJECT APPROACH A computer model of the entire water distribution system, including every transmission and distribution system pipeline was created using H20NET by the City of Owasso in 1997. H20 NET is a hydraulic and water quality network model that operates in the AutoCAD Windows environment. Detailed information was gathered from existing documents, billing records, conversations with City staff, aerial maps of the City, existing and future land use maps of the City, plan drawings, pump, tank, and valve records, and other sources. In addition, City staff performed surveys to determine accurate tank elevations. The distribution system model was updated to include pipes in new developments since 1997. City staff reviewed the pipeline diameters for the entire model to ensure accuracy. The model was calibrated based on information gathered by City staff during two days of field- testing. Fire hydrants were tested and all system operations were recorded on May 31 and June 1, 2000. The data from these two days of testing was used to confirm that the model appropriately simulates real-world field conditions. The model was then configured to simulate a 24-hour period. The approach in evaluating the existing system is to simulate the most stressful conditions, typically either the peak hour or the maximum day plus fire conditions. Both conditions were evaluated as part of this master plan. Following the evaluation and identification of needed improvements to the existing system; a model of the year 2020 was developed and analyzed to determine necessary future system improvements. Recommendations for all improvements, existing and future were prioritized according to system needs. Finally, construction costs were developed. WATER SYSTEM FINDINGS distribution 150 psi when were as follows the Ow as so water is between 115 psi and hydraulic criteria. However, findings system are critical to the meter connections the minimum The Owasso water distribution system ES-1 .. MONTGOMERY WATSON EXECUTIVE SUMMARY filled nor be tank cannot 69 storage the pressures fall below 110 psi on a peak day the can system pressures be maintained above 35 psi were the valves system. When were located in the distribution were increased by 25 psi Numerous closed valves opened the system pressures 2 The low the City of Owasso range from 579 feet to 730 feet. warrant the creation of a high pressure zone and a The ground elevations in changes in ground elevations pressure zone 3 (fill and empty) on an average demand day. This disinfectant residuals. The lowered disinfectant The current storage tanks do not cycle leads to stagnant water and lowered residual could have potential negative health impacts 4 the capacities required on a to handle The existing transmission mains are under sized peak demand day. 5 WATER SYSTEM RECOMMENDATIONS Facilities recommended for the Owasso distribution system are as follows Create a new pressure plane (upper pressure plane) including the area north of 86th street as well as a small area south of 86th street (shown in the Owasso Water Atlas in grid 292 B and D) 1II be served by the upper pressure (this area will Abandon the existing booster station 1II zone) Abandon the HWY 169 Tank. The hydraulic grade line (HGL) in the new upper pressure plane will be such that the existing 169 Tank would stay full under all normal operating conditions. This would likely lead to difficulties in maintaining the disinfectant residual and possibly lead to taste and odor problems O!I Construct a new 2.0 MG elevated storage tank in the upper pressure plane. The proposed location for the new elevated storage tank is east of Garnett Road midway between 96th Street and 106th Street in the Ator Heights area. This location was selected because the elevations in this area are the highest in the Upper Pressure Zone. The operating levels of the new elevated storage tank are 1II 715 Feet 815 Feet 860 Feet at Tank Level: Level Ground Leve Bottom Water Overflow Water is within the normal tank is changed and the Increase The height of the proposed storage tank is 140 feet. This heigh range for the elevated tanks. If the location of the proposed new total height of the tank increases beyond 150 feet, then the cost will approximately $6,000 for every foot above 150 feet. ES-2 MONTGOMERY WATSON EXECUTIVE SUMMARY 10-inch meter connection station will be configured as n-line pump station at the site of the current The new pump the upper pressure zone Construct a new to Tulsa to serve follows 1II be two 100-horsepower pumps (one duty pump and one standby pump) be provided in the pump station layout for future additional pumps in ~ There will Space will 2015 A bypass line will be included in the pump station since much of the time the upper pressure zone will be served directly from Tulsa pressure without any pumping. Pumping will not be required during low demand periods. In high demand periods, pumping will only be required during the day when the Tulsa supply pressure drops. A storage tank is not required at the new pump station. The supply pressure from the Tulsa meter connection is adequate to use an in-line pump station. ~ ~ The lower pressure zone was designed such that no pumping is required, even in peak demand conditions. A pressure-reducing valve (PRV) will be used to control pressures in the lower pressure zone. The PRY settings will be 90 psi during low demand periods and 120 psi during peak demand times. This PRY will be located in the new pump station for convenience of access and maintenance 1II Abandon the Ator Tank. The elevation of this tank is such that it cannot be used as usable system storage. Consideration was given to using the Ator tank as a supply tank for a transfer pump station between the lower and upper pressure planes. However, the recommended new pump station discussed above does not require a tank. @ Remove existing PRVs and control valves downstream of the Tulsa meters (except for the new PRY in the new pump station described earlier.) This will allow the lower pressure plane to be fed from the Tulsa system pressure without any pumping 1II The proposed improvements will require the construction of new transmission mains. The existing transmission mains will need to be paralleled with new pipes to increase the capacity of the existing system. New transmission mains will need to be constructed to extend to areas outside the Owasso service area. @ is It is devices are electronically log document the pressure changes from Tulsa under If the inlet pressures fall below 70 psi then the lower pressure require pumping on peak demand days critical to the lower installed that pressure zone. will from the Tulsa meter that pressure monitoring the inlet pressures from Tulsa. This will different demand scenarios may The inlet pressure recommended O!I plane The cost for each phase this report) shows the CAPIT ALIMPROVEMENT PLAN COSTS divided into five phases (located at the back of The capital improvement plan (CIP) was can be seen below in Table ES-l. Figure 5-6 ocations of the major infrastructure improvements the needs of the existing water the hydraulic criteria on mprovements necessary to address mprovements will allow Owasso to meet Phase I of the CIP are the distribution system. These ES-3 MONTGOMERY WATSON EXECUTIVE SUMMARY a peak demand day. The improvements include the creation of a new pressure plane, a new booster pump station a 2.0 MG elevated storage tank, and paralleling the existing transmission mains Phase n of the CIP includes replacing all pipes less than 4-inches, the replacement of the existing lO-inch meter with a 24-inch meter, and a new transmission main. Phase III of the CIP are the installation of new transmission mains in areas where there is currently no Phase IV of the CIP includes the installation of two more pumps at the booster and new transmission mains. Phase V of the CIP requires new transmission development pump station mams Costs Phase Time of Phase Project Cost of CIP I Installations Immediately $12,801,295 II Installations by Year 2005 $1,134,600 III installations by Year 2010 $6,479,000 IV installations by Year 2015 $762,600 V Installations by Year 2020 $781,200 Total $21,958,695 MONTGOMERY WATSON ES-4 Summary of Phased CIP Project Table ES-1