FROM: Group 4: David Hunter, Carl Jones, Lee Duong, SUBJECT: RECOMMENDATION FOR CHOOSING AN ALTERNATIVE

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1 Cover memo TO: Brent Adams, CEE Professor FROM: Group 4: David Hunter, Carl Jones, Lee Duong, Rhonda Peterson SUBJECT: RECOMMENDATION FOR CHOOSING AN ALTERNATIVE WATER SOURCE/SYSTEM REF.: Your letter of request, September 10, 2003 DATE: January 5, 2004 DIST.: Sonia Manuel-Dupont, Project Supervisor Smithfield City will not have an adequate supply of culinary water in the future. Their current supply is adequate for only another 5 years (Gass 1996). We were asked by you to research and derive a solution for this problem. After discussing as a group the various alternatives that could be implemented, we decided on four alternatives that would be the most effective. Each of us in the group researched articles and conducted personal interviews to determine the most appropriate solution. From our findings we have gathered that the most effective alternative is installing a new well that will have enough supply to meet future demand. Executive summary used in place of abstract Executive Summary The population of Smithfield City is growing rapidly. The current water supply for Smithfield is not adequate to meet the needs of the city over the

2 next 25 years. We need to find a source to provide an additional 70 million gallons of water per month to Smithfield City in order to have an adequate water supply for the next 25 years. We have researched the problem in scientific journals and books and have spoken with the Smithfield City Engineer and also others who deal directly with water supply. Our purpose of communication is to inform you of our 4 researched alternatives: (1) development of a new well, (2) no action, (3) installation of a dual system, and (4) water reuse. Only the development of a new well will supply enough water for Smithfield City over the next 25 years. Development of a new well was ranked best on cost, feasibility, and adequacy, and average on maintenance and impact on the environment. Therefore, we recommend the development of a new well to provide the necessary water for Smithfield City.

3 Title page Recommendation for Installing a Well for Smithfield City To: Brent Adams CEE 361 Professor From: Group 4 Dist: Dr. Sonia Manuel-Dupont Project Supervisor January 5, 2004

4 Sections numbered per CBE and CMS multiplenumeration system 1.0 Introduction and Problem Statement The City of Smithfield currently receives most of its culinary water from springs in Smithfield Canyon. There are 8 springs near the top of the canyon and 3 springs located further down the canyon. These springs produce an estimated flow rate that varies seasonally from 1800 gallons per minute in the spring to 1100 gallons per minute in the winter (Gass 1996). In addition to the springs, Smithfield has a secondary water supply provided by Introduction a 12 inch diameter, 40-foot-deep well located at Forrester Acres, west of the city. Water is pumped from this well during 3 or 4 months out of the year, only as a secondary water source to provide for residential summer irrigation. This well was recently modified to be able to supply up to 1500 gallons per minute but rarely runs at such capacity (Forsgren 1995). With full use of the springs and supplementation from the well, a minimum of 77 million gallons of water per month can be supplied to Smithfield at all times. Problem statement The current water supply is enough to sustain the residents of Smithfield. However, the population of Smithfield City is growing rapidly; therefore, Page number centered at the bottom of each page additional water must be found to supply the future 1

5 residents of Smithfield. The population, as of now, is about 6800 people (Gass 1996). The average water use per service is 36,862 gallons per month. Our predictions show that 14,346 people will be living in Smithfield City by the year 2021 and the amount of water they use will average approximately million gallons per month, assuming the amount of water use per service remains constant. Appendix B contains the equation used to predict the population growth and a yearly prediction of population for the next 25 years. Appendix C contains information on the current and projected water use. The difference between the minimum current water supply for Smithfield (77 million gallons per month) and the predicted water use in 25 years ( million gallons per month) is million gallons per month. We used 70 million gallons per month as the amount of water that Smithfield needs to meet the water demand in the year First-level heads centered Literature review included in discussion of proposed solutions 2.0 Four Proposed Alternative Solutions Given the problem of finding an additional water supply, we researched Smithfield s current population and water supply to make predictions for the next 25 years. We also researched 4 different 2

6 alternatives to find out what would be the best option to meet the expected demand. The alternatives considered were (1) drill a new well, (2) take no action, (3) implement a dual water irrigation system, and (4) recycle graywater. Second-level heads flush left and underlined 2.1 Drill a New Well The 1st alternative is to drill a new well for culinary water. This new well will be located on the north end of the Smithfield City golf course. Sources cited by author name and year, with no comma There is a large protected aquifer in that area (Gass 1996). The well will be about 400 feet deep, and it will use a 16-inch-diameter pipe. After the water leaves the well, it will pass through a chlorine gas chlorinator. The chlorine mixes with the water to disinfect it. Time is required for the chlorine to treat the water, so the water will enter an 18-inch pipe to slow down the velocity of the water. The water will then travel 2500 feet to connect with the existing water lines (Gass 1996). The system will be run automatically. Monitors in the storage tank and water lines will inform a computer when the storage supply is low. The computer will then activate the well to supplement the water demand. When the storage water is sufficiently recharged, the computer will shut down 3

7 the well, thus conserving energy and the water in the aquifer. 2.2 Take No Action The 2nd alternative is that of no action. This means that Smithfield s water system would remain the same and run at present capacity. 2.3 Implement a Dual Water Irrigation System The 3rd alternative that was considered is the implementation of a dual water irrigation system. A dual water system consists of 2 parts: (1) a culinary distribution system to provide potable water for residential use and (2) a distribution system to provide untreated, raw water for irrigation purposes (Vaughn 1995). Approximately 65 percent of the households in Smithfield are currently using some type of dual water irrigation system. Almost all of those using the current dual system are supplied water by Smithfield Irrigation Company (Gass 1996). Implementation of a dual system would consist of routing canals and irrigation lines to those residences that are not using dual water and also to any new homes in the city. Under this alternative, irrigation would be provided separately for everyone, and the strain on the culinary supply would be reduced. 4

8 2.4 Recycle Graywater The 4th alternative that was considered is recycling graywater. Recycling graywater is a relatively inexpensive and effective way to reuse waste water. Greywater is defined as untreated household wastewater which has not come into contact with toilet waste. Greywater includes used water from bathtubs, showers, bathroom wash basins, and water from clothes washing machines and laundry Direct quotation requires page number tubs. It shall not include wastewater from kitchen sinks or dishwashers (Pope 1995, p 2). A schematic of graywater reuse for a typical residential home is listed in Appendix D, Figure D-1. After clear water has been used in a home, it becomes graywater. The water then goes through a settling and filtration process; it then can be reused in some areas of the home. Graywater is most suitably reused for subsurface irrigation such as that of nonedible landscape plants. This cuts down on the amount of culinary water used for lawn irrigation. All of the information (including values) given under this alternative is given under the assumption that, as with the dual system, only 35 percent of the present homes in Smithfield City would be affected by a graywater system. A graywater system will be useless 5

9 to the people who receive irrigation water separately from their culinary supply. We assumed that the number of connections that currently use water from the canal irrigation system will remain relatively constant through the next 25 years. 3.0 Research Methods 3.1 Five Evaluative Criteria Each of the alternatives we have described has been examined with respect to 5 criteria. The criteria we have selected, in order of significance, are (1) cost of implementation, (2) feasibility, (3) adequacy of supply, (4) maintenance required, and (5) impact on the environment. Table 1 shows the alternatives and the criteria. The alternatives are ranked on a scale from 0 to 2, 0 being the least favorable and 2 being the most favorable. The rankings are multiplied by a weighting factor of 1, 2, or 3, depending on the importance of the criterion involved. A description of our criteria is as follows: 1. Cost--The complete cost of installation and implementation of the alternative 2. Feasibility--The ease of implementation and whether it is allowable 6

10 3. Adequacy--Whether or not it will supply a sufficient amount of water 4. Maintenance--The person-hours and cost for upkeep 5. Impact on the Environment--How the alternative affects land usage and habitat Table used to report data Table 1. Weighted Selection Criteria for Water Supply Alternatives Alternatives No Dual Multiplier Criterion Well Action Water Reuse 3 Cost Feasibility Adequacy Maintenance Environment TOTALS Based on our findings and the rankings provided by Table l, our recommendation to Smithfield City is to construct a new well to provide water for its domestic supply. In sections , students analyze the four alternatives in detail, in light of their criteria. 7

11 4.0 Results and Discussion With the increasing population, Smithfield City has concerns over water demand. Our research shows that with the increasing population, Smithfield will need to provide more water for its citizens. We developed alternatives to help Smithfield meet demands. Statement of suggested solution to the problem Given the 4 alternatives--groundwater well, no action, dual water system, and water reuse--we believe constructing a groundwater well is the best choice for the City of Smithfield. For a reasonable price, an efficient well can be built to meet the predicted needs of Smithfield with low maintenance and minimal impact to the environment. The well could carry Smithfield into the next century and beyond. 8

12 CBE nameand-year citation system Personal communication Journal article Appendix A References Burgess M, Distributor, Fairbanks Morse Pump Corp Dec 3. [Personal communication]. Carter R Trickle-down economy. Sierra 79: Page nos. Title Journal Volume [DWR] Division of Water Resources State water plan--bear River Basin executive summary [online]. Available from: WTRRESC/WTRRESC.htm. Accessed 1996 Nov 8. [Forsgren] Forsgren Association, Inc Computer simulation and master plan for domestic water system: prepared for the Smithfield City Corporation. Salt Lake City: Forsgren Assoc., Inc. Gass J, Smithfield City Engineer Nov 8. [Personal communication]. Internet source Gelt J Home use of greywater: rainwater conserves water--and may save money [online]. Available from: arroyo/071.rain.html. Accessed 1996 Nov 8. Technical report [IAPMO] International Association of Plumbing and Mechanical Officials Uniform plumbing code. Los Angeles: Plumbing Assoc. 9

13 Pope T Greywater, a recyclable resource [online]. Available from: article1.html. Accessed 1996 Nov 8. [Roscoe] Roscoe Moss Co The engineers manual for water well design. Los Angeles: Roscoe Moss Co. Rowland P. Assistant City Engineer Nov 17. [Personal communication]. [Vaughn] Vaughn Hansen Associates, in association with CH2M Hill and Water Research Laboratory, State University Identification and assessment of certain water management options for the Wasatch Front: prepared for the State Division of Water Resources. Wilding D, Water Department Head Dec 2. [Personal communication]. In addition to Appendix A (References), students included the following appendixes: Appendix B: Population Projections Appendix C: Projection of Water Flow Rates Appendix D: Schematic of Graywater Reuse System Appendix E: Individual Cost of Water Well Construction Appendix F: Discussion of Cost of Implementation of a Dual System Appendix G: Calculations for Percentage of Water Use 10