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2 SANDY LAKE ESTATES WATER SUPPLY PROJECT LEVEL II FEASIBILITY STUDY Prepared for Wyoming Water Development Commission EXECUTIVE SUMMARY December, 99 CIVIL ENGINEERING PROFESSIONALS, INC. 355 North Lincoln Casper, WY 8260

3 SANDY LAKE ESTATES WATER SUPPLY PROJECT LEVEL II FEASIBILITY STUDY Prepared for Wyoming Water Development Commission EXECUTIVE SUMMARY December, 99 CIVIL ENGINEERING PROFESSIONALS, INC. 355 North Lincoln Casper, WY 8260

4 EXECUTIVE SUMMARY This Executive Summary provides an overview of the results of the Sandy Lake Estates Water Supply Project, Level II Feasibility Study. The purpose of the Study was to determine the feasibility of supplying treated water to the Sandy Lake Estates Subdivisions. The report provides descriptions and evaluations of water supply alternatives for the area. A conceptual design and cost estimates are provided for the selected alternative along with the estimated water user rates. INTRODUCTION The Sandy Lake Estates Subdivisions are located in Natrona County, northeast of the Town of Evansville, Wyoming. The area began developing in the late 970's and early 980's as a result of the economic "boom" experienced in the greater Casper area. The two subdivisions are composed of 05 platted lots, 56 are in Sandy Lake Estates, and 49 are in Sandy Lake Estates No.2. The water supply for the area is provided by individual onsite wells. In 983, the two subdivisions joined together to form the Sandy Lake Estates Improvement and Service District hereinafter referred to as the "District". Soon after development of the District, many residents began to experience problems with the water quality and production capacity of their water well supplies. Many of the residents whose wells have failed, now haul water from nearby municipal suppliers. Others, whose water quality is not potable, purchase bottled water for domestic purposes, and only use the well water for toilets, showers and irrigation. - - EXECSUM 2/23/9

5 POPULATION AND WATER DEMAND PROJECTIONS The planning area boundary used in the Study is shown in Figure, (presented later in this report). The planning area was limited to the two Sandy Lake Estates subdivisions, and the corridor extending northward from U.S. Highway 20/26 to the subdivisions. There are 05 platted lots in the two subdivisions, and approximately 80 are occupied with homes. The current population is estimated at 246 and is expected to increase to 35 by the time the platted lots are all occupied. Residential water demand projections for the District when fully developed, are summarized in Table. Fire flow demands were determined to be 000 gallons per minute (gpm) for a duration of two hours. TABLE WATER DEMAND ESTIMATES (Population 35) DEMAND RATE (gpcpd) AVERAGE MAXIMUM PEAK DAY DAY HOUR TOTAL DEMAND (gjd) AVERAGE MAXIMUM PEAK DAY DAY HOUR 47,000 30, ,000 WATER SUPPLY CONSIDERATIONS Two approaches were taken in order to evaluate a water supply system for the District. One approach consisted of developing a water supply and distribution system which would simply meet the domestic needs of the District's residents. The other approach was to provide a water supply system that would meet the domestic needs of the residents and would also provide EXECSUM 2/23/9

6 adequate volumes of pressurized flow to fight a residential fire in the District. A summary of the water storage requirements for the two approaches is given in Table 2. TABLE 2 SUMMARY OF WATER STORAGE REQUIREMENTS WITHOUT WITH FIRE TYPE OF STORAGE FIRE FLOW FLOW CAPABILITIES Emergency (gal) 47,000 47,000 Fire Flow (gal) ,000 Peak Hour (gal) 6,600 6,600 Total Storage 53,600 73,600 Use 60,000 80,000 There are two potential municipal water supply sources that could provide water to the District. One source is the Town of Evansville and the other is the City of Casper. Water supplied from the current Evansville system would need to be pumped to the District because the District is generally above Evansville's zone of service. Water supplied from the Casper water system would not need to be pumped because Casper's zone of service can provide adequate pressure to the area. Initial comparisons indicated the cost to purchase water from Evansville was more expensive than from Casper. However, Casper's price for water did not include operation or maintenance services, while initially Evansville's did. WATER SUPPLY ALTERNATIVES Three basic alternatives were developed for supplying municipal water to the District. Each of the three alternatives was broken into two similar alternatives, with and without the EXECSUM 2/23/9

7 capability to provide fire flows. There are two feasible connection points to the Evansville system, one at the north end of Mystery Bridge Road in Brookhurst Subdivision, and the other at the end of the existing 8 inch transmission line located along the Old Glenrock Highway at the entrance into the Brookhurst Subdivision. These two alternatives were designated as Alternative No. A and No. lb. By up-sizing the system to provide fire protection, the designations became Alternatives No. A-F and No. B-F respectively. The most feasible alternative for a connection to the Casper system is at the end of the existing water transmission line which serves the Casper Balefill Facility. A transmission line could be extended eastward from that location to the District. The designation for this alternative was Alternative No.2, and the system which would provide fire flows to the District was designated as Alternative No.2-F. Preliminary conceptual designs and cost estimates were developed for all six alternatives. The total project cost consists of construction, engineering and land acquisition costs. A summary of the estimated total project cost for each of the Alternatives is given in Table 3. The costs were broken down into the following two categories: WWDC Eligible - Those portions of the project costs associated with the water supply system including transmission line, meter vault, booster station, and water storage tank. NON-WWDC Eligible - Those portions of the project costs associated with the distribution system to the homes such as water lines, meter pits and water services EXECSUM 2/23/9

8 TABLE 3 SUMMARY OF ESTIMATED TOTAL PROJECT COSTS WWDC NON-WWDC TOTAL PROJECT ALTERNATIVE NO. ELIGIBLE ELIGIBLE COSTS la $ 703,447 $ 473,636 $,77,083 la-f 820, ,48,393,475 IB 822, ,203,347,75 IB-F 937, ,557,577, ,442 45,76,376,58 2-F,04, ,424,587,42 ECONOMIC EVALUATION The District's ability-to-pay was evaluated in an attempt to estimate what residents might be able to pay for the proposed improvements. One reasonable measure of the ability-to-pay is the cost of operating the individual water wells. Three types of individual supply systems were assumed to exist; () good wells which require no treatment, (2) poor wells which require considerable treatment, and (3) failed wells in which potable water must now be hauled to the residence. The overall average cost to operate and maintain the individual system was estimated to be $65 per month. Evaluation of fire insurance rates indicated the average homeowner in the District could save $7.42 per month if a public water supply system were available which could provide fire flows. The combination of costs spent on the existing water supply system, plus the savings realized by reduced fire insurance rates, indicated an overall average ability-to-pay of $82 per month per household EXECSUM 2/23/9

9 SELECTED ALTERNATIVE Following a presentation of the six water supply system alternatives at a public meeting, the District residents voted to pursue Alternative No. B-F as the alternative of choice. Negotiations for a water purchase agreement with Evansville were begun in the fall of 99. As part of the negotiations, Evansville requested funding assistance from the WWDC for construction of a water storage tank to replace the aging Scott Hill Reservoir. The new water tank would be constructed large enough, and at an elevation high enough, to eliminate the need for a booster station or a water storage tank in the District. In return, the Town established a new ordinance enabling Evansville to sell wholesale water to the District at a rate of $.05 per 000 gallons. However, Evansville would not operate or maintain the District's system, or the transmission line north of the south bank of the North Platte River. The water purchase negotiations caused significant changes in the conceptual design for the District's water supply system. With a new tank having an overflow elevation the same as Casper's, the previously proposed water storage tank and booster pumping station would no longer be required. A 6 inch diameter transmission line (rather than an 8 inch line) would be needed however, in order to provide the 200 gpm maximum day and fire demands to the District from the remote tank location. The District's metering facility would be constructed on the south side of the river. A one-time tap fee of $48,375 would be charged to the District for connecting to the Evansville system. The conceptual design for the selected alternative is shown in Figure EXECSUM 2/23/9

10 --'.--- ~. " j ' ~" " o 2000' FIGURE SELECTE~L :ESIG N CONCEPTU SUPPLY ALTATER SANDY L ERNATIVE WATER SU:~~YESTATES PROJECT 5coffhil/ ~e:s~rvqi,-.-. Civil Engineering Professional., Inc

11 Cost estimates for the selected water supply alternative are given in Tables 4, 5, and 6. It should be noted that the Evansville Water Storage Tank is proposed to be designed and constructed as a separate project, not as a part of the District's project. It is also proposed that the Brooks/Hat Six area will share in a portion of the cost of extending the 8 inch diameter transmission line along the old Glenrock Highway, and will construct a connection to the transmission line to obtain service for that area. The cost sharing agreement is pending, and once secured should make the Brooks/Hat Six area eligible for WWDC funding assistance. ECONOMIC ANALYSIS OF SELECTED ALTERNATIVE The estimated cost of the project needed to serve the District is $,829,048, with $,006,623 being eligible for WWDC funding assistance. Based upon traditional funding sources and availability, project funding is expected to come from the sources shown in Table EXECSUM 2/23/9

12 TABLE 4 ESTIMATED PROJECT COSTS - SELECTED ALTERNATIVE QUANTITY AND COST ESTIMATES WATER SUPPLY - WWDC FUND ELIGIBLE ESTIMATED UNIT TOTAL ITEM UNITS QUANTITY COST COST 8 inch transmission line 8 inch gate valves 8 inch fittings 6 inch transmission line 6 inch gate valves ** ** ** 2, ,400 3 $ ,000.00, , $75, , , , , inch fittings inch railroad undercrossing 6 inch river crossing 2 inch transmission line , , , , inch gate valves 7, , inch fittings Air release/vacuum valves select granular material Asphalt removal and replacement Seeding and mulching C.Y. S.Y , , , , , , , , Fire hydrants with valves & tees 7, , Meter manhole (at river crossing) 5, , Main Meter Pit (Sandy Lake Connection) 40, , Meter Pit (Brooks-Hat Six) 40, , SUBTOTAL CONSTRUCTION COST ENGINEERING DESIGN, PLANS, AND BID DOCUMENTS (0%) $744, , CONSTRUCTION COST PLUS ENGINEERING ENGINEERING-CONSTRUCTION PHASE (0%) PERMITS AND LEGAL FEES (2%) LAND ACQUISITION COSTS $88, , , , SUBTOTAL PROJECT COST CONTINGENCY (5%) $98, ,76.05 TOTAL PROJECT COST $,055,823 ** NOTE: The total estimated project cost is actually $,000,623 if the Brooks-Hat Six Meter Pit is excluded from the District's cost SL-!X4 2/7/9

13 TABLE 5 ESTIMATED PROJECT COSTS - SELECTED ALTERNATIVE QUANTITY AND COST ESTIMATES WATER DISTRIBUTION SYSTEM - WWDC NON-ELIGIBLE ITEM UNITS ESTIMATED QUANTITY UNIT COST TOTAL COST 8 distribution line 8 inch gate valves 8 inch fittings 8 inch air release/vacuum valves Select granular backfill C.Y $ $ Asphalt removal and replacement S.Y Gravel removal and replacement Seeding and mulching inch services with meter pits Fire hydrants with valves and tees SUBTOTAL CONSTRUCTION COST ENGINEERING DESIGN. PLANS AND BID DOCUMENTS (0%) $ CONSTRUCTION COST PLUS ENGINEERING ENGINEERING-CONSTRUCTION PHASE (0%) PERMITS AND LEGAL FEES (2%) LAND ACQUISITION COSTS TAP FEE $ SUBTOTAL PROJECT COST CONTINGENCY (5%) $ TOTAL PROJECT COST $ SL-EX5 2/7/9

14 TABLE 6 ESTIMATED PROJECT COSTS - EVANSVILLE TANK QUANTITY AND COST ESTIMATES ITEM UNITS ESTIMATED QUANTITY UNIT COST TOTAL COST Disconnect and abandon existing reservoir Excavation/Fill Concrete Foundation Site Piping: 2 inch supply 2 inch valve 2 inch fittings 6 inch drain with overflow 6 inch valve 6 inch fittings Rip Rap Drain Structure Site Graveling 30 ft. access road Controls manhole Drain manhole Tank Fencing Telemetering. controls Site cleanup. restoration L.S. C.Y. L.S. S.Y. S.Y. S.Y. L.S. L.S. L.S $ $0, , SUBTOTAL CONSTRUCTION COST ENGINEERING-DESIGN. PLANS AND BID DOCUMENTS (0%) $ CONSTRUCTION COST PLUS ENGINEERING ENGINEERING-CONSTRUCTION PHASE (0%) PERMITS AND LEGAL FEES (2%) LAND ACQUISITION COSTS $ SUBTOTAL PROJECT COST CONTINGENCY (5%) $ TOTAL PROJECT COST $ SL-EX6 2/7/9

15 TABLE 7 FUNDING SOURCES FOR SANDY LAKE ESTATES WATER SUPPLY PROJECT WWDC Eligible Portion (Cost WWDC Grant (67%) WWDC Loan (33%) $,006,623) $670,47 330,206 $,006,623 Non-WWDC Eligible Portion (Cost = $822,425) FLB Grant (50% does not include tap fee) One Cent Sales Tax FLB Loan $387, ,000 20,400 $822,425 A typical monthly water user fee was developed for the selected alternative. The components and costs for the user fee are summarized in Table 8. The fee is based upon an average usage of 2,000 gallons of water per month per household, and 80 households. In addition to the costs shown in Table 8, it is estimated that the average household will pay $,000 to $,500 to disconnect their existing water systems and connect to the new water system. The cost of this work on private property is not eligible for funding assistance through any city or state agencies. TABLE 8 TYPICAL MONTHLY WATER USER FEE FOR THE DISTRICT Debt Retirement (Spread over all lots) WWDC loan ($330,206, 30 years, 4%) FLB loan ($20,400, 30 years, 8.5%) Total Debt Retirement Water Purchase (2,000 gal. per household) O&M Cost ($27,500 spread over 80 households) Sinking Fund (Spread over 05 lots) $ $ "Typical" Total Monthly User Fee $ EXECSUM 2/23/9

16 IMPLEMENTATION If funding from the WWDC is approved during the 992 legislative session, design for the project can be completed by the end of 992. Construction is expected to begin in early 993, and should be completed by the end of EXECSUM 2/23/9