SPRINGVILLE CITY WATER TANK AND WELL PROJECTWILLIAM GARNER, JEREMY FOWLER, AUSTIN JASPER

The city of Springville has been experiencing a period of rapid growth. The cities population is expected to grow from about 30,000 residents to over 60,000 over the next 30 years (Springville City Culinary Master Plan 2013 update, pg. 13). To alleviate the coming deficit our team has been developing plans for a new water well, water tank, and pipeline between the proposed well site and the proposed water storage tank. The well will be located at about 200 North and 900 East and will bring water to a future water tank located on the mountain side near 970 east and 400 North. The water tank will provide between 2 and 4 million gallons of water for future developments located in the Westfields pressure zone and current residents of Springville City.

Cost Estimation

Introduction

After assessing the estimates of the water tank, pump, pipeline, easement, flux, and contingency the total expected cost is $3,223,588.13. The cost break down is shown in Table 1.

Well data does not exist for the proposed well, therefore; data from a nearby well in Springville was used in the calculations and preliminary design. The well bottom will be approximately 477 feet below the surface. We propose that a line shaft pump be used. Figure 1 below is the pump performance curve for a 350 hp pump which will provide the necessary 3000 gpm.

The cost of this pump is $60,938.00. This does not include installation or pertinences.

We used friction head loss in the pipes from the tank to the extreme elevations to find the needed tank elevation. This ensures that the appropriate water pressure will be delivered. We found the required elevation to be between 4770 ft. and 4820 ft. We chose 4806 ft. as the top elevation of the resting water. The best location we found was at 40°10'23.75"N 111°35'30.35"W.

Our 4 million gallon tank was designed according to “Prestressed Concrete a Fundamental Approach, Fifth Edition Update ACI, AASHTO, IBC 2009 Codes Version” (Edward G. Nawy, 2010) and other government regulatory standards.

Pump Analysis

Tank Design

Pipe RouteIn deciding a pipe route we considered several variables including length, number of bends, easements, diameter, and constructability. We came up with four routes the best one is shown in Figure 2. We chose this route because it has the least effect on homeowners.

We recommend 14 inch ductile iron pipe from the pump up to the water tank. We considered the option of horizontal drilling, but it needs further investigation.

We received a bid from Sunroc. The cost was $277,492.50.

Figure 2. Pipe route from well to tank.

Figure 1. Pump performance curve.

The wall design was an iterative process; it consisted of choosing a wall thickness, calculating the maximum hoop stress and bending moments, and testing to see if the wall thickness would hold. We chose a wall thickness of 12 inches, a concrete design strength of 5000 psi, and a pre-stressing strength of 180000 psi. Specifications for the tank are shown in Figure 3.

We considered a domed roof design, but the cost for a buried domed roof was expensive. We received two cost estimates, one from DN Tanks for a flat roof and another from Precontanks for an unburied domed roof. The costs were $2,200,000 and $1,283,000 respectively. We recommend DN Tanks design and cost.

Figure 3. Tank Cross Section with Design Specifications.

Table 1. Cost Break Down