Park City and Snyderville Basin Water Supply Study Special Report

Executive Summary 

Overview 

Historically, water suppliers in Park City and Snyderville Basin have relied primarily on 

groundwater for their municipal and industrial (M&I) water. Because of the extensive 

development of the groundwater sources, there is concern that there may be limited potential for 

additional development of the groundwater as a reliable long-term water supply. The recent 

drought (1999-2004) has raised further questions regarding the quantity and reliability of the 

existing groundwater development within the Basin. This problem is being compounded by the 

continuous rapid growth in the Basin, which has become a highly desirable residential and 

recreational community. 

There is significant local interest in determining the long-range water needs of the Basin and 

identifying feasible options to provide additional water for future needs. Over the past several 

years, government agencies and several private entities have explored various options to develop 

additional water supplies. However, a comprehensive evaluation of the overall water needs 

within the Basin had not been conducted, nor had a comparison between alternative plans been 

examined in an objective manner. 

In 2001, the U.S. Army Corps of Engineers (COE) was funded and directed by Congress to 

conduct a feasibility study for Park City on water supply options, titled the “Park City Water 

Supply Infrastructure Study”. The COE completed significant work prior to Reclamation’s 

involvement. Page 120 of the FY 2004 Energy and Water Appropriations Conference report 

states: “The conference agreement includes $500,000 for the Bureau of Reclamation to continue 

a feasibility study of water supply infrastructure improvements in Park City, Utah.” Reclamation 

received additional funding in FY 2005 and FY 2006. This study is being conducted pursuant to 

the authority and with the funding provided in these appropriations. 

The purpose of this Park City and Snyderville Basin Water Supply Study is to evaluate the future 

water needs within the rapidly growing Park City and Snyderville Basin area and to formulate, 

compare, and prioritize options that could be pursued to provide for the M&I water needs 

expected through 2050. This report presents the findings and recommendations of the study. 

Projected M&I Demands 

The Park City and Snyderville Basin area is experiencing some of the fastest growth in Utah. 

This growth has included commercial, institutional, and residential development. The entire area 

is experiencing an accelerated change from a regional ski resort destination to a diversified yearround vacation and living community, as well as a bedroom community for the Salt Lake 

Metropolitan area. 

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Park City and Snyderville Basin Water Supply Study Special Report

Population within the study area is projected to increase from the present (2001) approximately 

24,000 to about 64,000 in 2030 and 86,000 by the year 2050. If per-capita use rates were to 

continue as at present, this increased population would result in an M&I demand of 

approximately 25,000 acre-feet per year in 2030 and 32,000 acre-feet per year by 2050. 

However, assuming current water conservation goals are met, the projected demands would be 

about 23,000 acre-feet per year in 2030 and 27,000 acre-feet per year by 2050. 

As explained in Chapter 4, additional demands have been placed on the system to meet in-stream

flow and wastewater dilution requirements (1,100 acre-feet per year in 2030 and 1,600 acre-feet 

per year in 2050), and to replace susceptible mine tunnel flows which have been relied on by 

Park City (2,000 acre-feet per year for both 2030 and 2050). These additional demands increase 

the projected water needs to 26,100 acre-feet per year in 2030 and 30,600 acre-feet per year in 

2050. 

Reliable Water Supply

Table ES-1 shows, by water provider, estimated annual water supplies currently available to 

meet M&I demands within the study area. This current long-term reliable water supply is 

approximately 14,000 acre-feet per year. Total current use is approximately 9,800 acre-feet, 

leaving a current reserve of about 4,200 acre-feet to meet fire suppression and other emergency 

needs. Chapter 4 presents a detailed discussion of the reasons for and the importance of this 

reserve. Also explained in Chapter 4 is the rationale for increasing the “reserve” need from the 

current 4,200 acre-feet per year to 6,500 acre-feet per year in 2030 and 7,500 acre-feet per year 

in 2050. 

TABLE ES-1 

2003 Annual Water Production Estimate 

(Units: Acre-Feet per Year) 

Water Supplier Total In-Basin

 (AF/Yr) 

 2001 Actual Use 

 (AF/Yr) 

Community Water Company 281 163 

Gorgoza Mutual Water Company 1,424 583 

High Valley Water Company 166 75 

Mountain Regional SSD 2,467 1,697 

Park City Municipal Corporation 5,716 4,728 

Summit Water Distribution Co. 3,340 2,065 

Summit Co. Service No. 3 203 80 

Timberline Special Imp. District 59 16 

Others 371 427 

Totals (Rounded) 14,000 9,800 

Surplus/Reserve 4,200 

Not included in the 14,000 acre-feet per year current supply are more recently developed water 

supplies and expected future in-Basin water development supplies. Those already developed 

include the 1,600 acre-feet per year supply provided by the recently completed Lost Creek 

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Park City and Snyderville Basin Water Supply Study Special Report

Canyon Pipeline project and the 1,000 acre-feet per year imported by Park City from the 

Jordanelle Special Service District. These supplies are discussed in greater detail in Chapter 4. 

Additional in-Basin supplies, assumed to be developed annually by the year 2050, include 300 

acre-feet additional groundwater and 500 acre-feet conversion of agricultural-use to municipaluse. Including these developed and anticipated future in-Basin supplies, and excluding the 

reserve need, the projected reliable water supplies of 9,800, 10,700, and 9,900 acre-feet per year 

for years 2001, 2030, and 2050, respectively, are required as shown in Table ES-2. 

Projected M&I Needs 

Projected M&I needs are computed by subtracting projected reliable supply from projected M&I 

demands. As shown in Table ES-2, the projected additional M&I needs (future development) are 

15,400 acre-feet for the year 2030 and 20,700 acre-feet for 2050. A detailed discussion of the 

analysis behind these numbers is presented in Chapters 2 through 4. 

TABLE ES-2 

Snyderville Basin Projected Future M&I Needs 

Units: Acre-Feet per Year 

Existing and Projected M&I Needs 2001 2030 2050 

Population 23,900 64,300 86,300

Calculated M&I Demand 9,800 25,300 32,000

 Water conservation 0 (2,300) (5,000)

Adjusted M&I Demand 9,800 23,000 27,000

 Minimum instream flow/wastewater dilution required 0 1,100 1,600

 Mine tunnel concerns – mine collapse, water quality 0 2,000 2,000

Projected Total M&I Demand 9,800 26,100 30,600

Calculated Current Supplies 14,000 14,000 14,000

 Lost Creek Canyon Project 0 1,600 1,600

 Jordanelle Special Service District imports 0 1,000 1,000

 Increased groundwater development 0 200 300

 Future agricultural conversions 0 400 500

 Reserve Capacity (4,200) (6,500) (7,500)

Projected Reliable Supply 9,800 10,700 9,900

Projected Additional M&I Needs (Future 

Development) 0 15,400 20,700

Future Development Options 

Nine options were identified for developing water to meet future needs. The first three are inBasin development options, while the remaining six are importation options. Four of the six 

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Park City and Snyderville Basin Water Supply Study Special Report

importation options (6, 7, 8 and 9), develop the same Weber Basin Water Conservancy District 

(WBWCD) water supply. Therefore, only one of the four could be considered for future 

development. 

Each of the nine Options was studied in detail to determine viability. A more detailed

description of the analysis is presented in Chapter 5. Of the nine Options, six were considered 

viable for further evaluation as shown in bold type in Table ES-3. Also shown is the water 

supply that would be developed by each, for a total potential development of 20,000 acre feet per 

year by 2030 and 21,600 acre-feet per year by 2050. 

TABLE ES-3 

Development Options Summary

Units: Acre-Feet per Year 

Development Options 2001 2030 2050 

In-basin Development 

 1 – Additional In-Basin Surface Water Storage 

 2 – Conjunctive Management of Surface & Groundwater

 3 – Water Reuse 0 2,000 3,600

Importation 

 4 – Provo River – JSSD 0 500 500

 5 – East Canyon Pipeline 0 12,5001 12,5001

 6 – Brown’s Canyon Pipeline 

 7 – Lost Creek Canyon Pipeline 0 5,0002 5,0002

 8 – Weber River via Weber Provo Canal 0 5,0002 5,0002

 9 – Lost Creek Canyon and Weber Provo Canal 0 5,0002 5,0002

Total Potential Development 0 20,000 21,600

1

Additional water right approvals and potential acquisitions may be needed to yield the full 12,500 acre-foot 

supply. 2

These options are dependent upon the same 5,000 acre-feet water supply as Option 7 – hence only one of 

the three can be developed. 

Option Evaluation 

Each of the six viable Options was evaluated against a set of criteria developed during the public 

involvement process of the study. Each criterion was generally applied on a per acre-foot basis. 

The study team divided the evaluation criteria into two separate categories: Economic Evaluation 

factors and Non-Economic Evaluation factors. Economic factors include capital cost and present 

value life cycle cost. Non-Economic factors include environmental, social, institutional, and 

system reliability. 

Results of the economic factors evaluation are shown in Table ES-4, with a more detailed 

explanation presented in Chapter 6 (Section 6.3.2) and in the Appendix. Potential impacts were 

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Park City and Snyderville Basin Water Supply Study Special Report

identified during the non-economic factors evaluation, however, none were considered 

sufficiently significant to prevent or limit development of any of the six Options. 

TABLE ES-4 

Economic Factors Evaluation Summary

Economic Factors Option 

3 

Option 

4 

Option 

51

Option 

71

Option 

8 

Option 

9 

Capital Costs (new) 2

(Units 1,000) $19,100 $2,700 $53,700 - $67,300 $25,500 $7,200 $14,400 

Capital Costs (total) 

(Units: 1,000) $19,850 $2,700 $69,300 - $82,900 $37,800 $7,200 $24,300 

Capital Costs per 

acre-foot capacity3 $5,510 $5,400 $7,920 - $6,630 $7,560 $1,440 $2,880 

Life Cycle Costs per 

acre-foot delivered $179 $744 $418 - $376 $369 $460 $426 

1 Option 5 costs are shown as a range, consistent with a capacity between 8,750 acre-feet per year and 12,500 

acre-feet per year, as explained in Sections 5.7.2 and 6.3.2. Also, costs for Options 5 and 7 are based on cost 

estimate Method 3 (see Table ES-5). 2

 Capital costs of new facilities only 

3 Based on capital costs (total) rather than capital costs (new). 

Preferred Plan 

Of the six options evaluated, only Options 5 and 7 are included in the preferred plan. Option 3 is 

not included because it is an in-Basin option, i.e. water reuse, which was assumed would be 

developed by local entities. Options 8 and 9 were eliminated because Option 7 is the highest 

ranking of the three and therefore becomes the preferred method for importing WBWCD water 

from Rockport Reservoir to the Snyderville Basin. Option 4 is eliminated because of high life 

cycle cost relative to the other options. 

With the options narrowed to two, a more detailed comparison of the two was conducted from

both an economic and non-economic perspective, in order to rank the options and make 

recommendations with regard to construction priority. This comparison is described in more 

detail in Chapter 6, Sections 6.3.2 and 6.3.3. A more detailed economic analysis showing four 

different methods of cost estimates is shown in Table ES-5. 

The economic comparison shows that the life cycle cost per acre-foot delivered (See Table ES-4) 

is slightly lower for Option 7 than for Option 5, but are within the accuracy of the estimates. 

Because the cost differences between the two are considered within the margin of error of the 

analysis, other factors must be considered to determine a recommended priority. 

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Park City and Snyderville Basin Water Supply Study Special Report

TABLE ES-5 

Option Cost Estimate Summary by Method

Options 

Method 11 

New

Facilities 

Only

Method 22 

All 

Facilities 

(USBR)

Method 33 

All Facilities 

(Includes 

Sunk Costs) 

Method 44 

(New

Facilities 

Contract

Cost Only) 

Option 5 - East Canyon Pipeline

(8,750 AF capacity and water supply)

 Capital Costs 

Capital Cost (Units: 1,000) $53,700 $76,000 $69,300 $39,900 

Capital Cost per AF Capacity $6,140 $8,690 $7,920 $4,560

Option 5 - East Canyon Pipeline

(12,500 AF capacity and water supply) 

 Capital Costs

Capital Cost (Units: 1,000) $67,300 $89,600 $82,900 $51,400

Capital Cost per AF Capacity $5,380 $7,170 $6,630 $4,110 

Option 7 - Lost Creek Canyon Pipeline

(5,000 AF capacity and water supply) 

 Capital Costs 

Capital Cost (Units: 1,000) $25,500 $40,300 $37,800 $19,000 

Capital Cost per AF Capacity $5,100 $8,060 $7,560 $3,800

1 Method 1 – Costs for new facilities only. Cost of existing facilities excluded (no sunk costs). Costs include 10% for 

unlisted items, 20% for contingencies, and 12% for engineering, design, and construction oversight. 2 Method 2 – Cost of all facilities (new and existing) as if none have been constructed. Costs include 10% for unlisted 

items, 20% for contingencies, and 12% for engineering, design, and construction oversight. 3 Method 3 – Cost of all facilities (new and existing). Existing facility sunk costs are added to cost of new facilities. 

Costs include 10% for unlisted items, 20% for contingencies, and 12% for engineering, design, and construction 

oversight. 4 Method 4 – Method 1 (new facilities only) - contract of “field” costs only – which includes 10% for unlisted items but 

does not include 20% for contingencies, or 12% for engineering, design, and construction oversight. 

As shown in Table ES-5, the capital cost for Option 7 is lower than the capital cost for Option 5. 

Also, Option 7 capital cost per acre-foot capacity for Methods 1 and 4 is less than costs for 

Option 5. However, Option 7 capital cost per acre-foot capacity for Methods 2 and 3 is inside 

the range of costs for Option 5. Cost differences between the two Options are so close that they 

are considered within the margin of error of the analysis, and therefore, do not indicate a 

conclusive preference of one over the other. 

The non-economic comparison, as mentioned above, found no potential impact that would 

prevent or limit development of either of the two Options. However, some could have 

significant impact on the timing and risk of development. 

Park City and other areas within the Snyderville Basin have an immediate need for additional 

water supplies, making timing of permanent water deliveries critically important. The available 

supplies are already behind the projected demand curve (Figures 4.1 and 6.1). Based on the 

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Park City and Snyderville Basin Water Supply Study Special Report

information presented in Chapter 5, and the analysis presented in Chapter 6, the non-economic 

factors comparison of the two Options ranks Option 7 ahead of Option 5. Considering both the 

economic and non-economic factors, Option 7 is ranked first for the following reasons: 

• A primary reason for the congressional legislation was to find a permanent solution to 

Park City’s immediate and critical need for 2,500 acre feet of water per year. Option 

7 is the least costly, would require only 21⁄2 miles of additional pipeline, and would 

require the shortest time to implement for Park City’s need. 

• Option 7 is a smaller project and has a lower new facility project capital cost, i.e. 

$25,500,000 instead of $67,300,000, which makes obtaining funding easier and 

faster. 

• Option 7 can be implemented in less time and with less risk. 

• Option 7 has fewer easements, water rights, and land use permit issues to resolve. 

• Option 7 has water delivery agreements in place.

• A majority of the infrastructure for Option 7 is already constructed. 

• Environmental compliance is expected to take less time because Option 7 is a smaller 

project with fewer expected adverse impacts. 

• Option 7 has a lower capital contract cost per acre-foot capacity, although both 

projects are relatively close and are considered within the margin of error of the cost 

estimates. 

The East Canyon Pipeline Project, however, is also needed and should move forward 

immediately and as expeditiously as possible to meet the future, rapidly growing, water needs in 

the other areas of the Snyderville Basin. 

Table ES-6 shows the priority ranking and the quantities of water recommended for development 

under each option. 

TABLE ES-6 

Preferred Plan 

Development Option Priority and Needs 

Units: Acre-Feet per Year

2030 2050

Priority Development Option 

1 Option 7 - Lost Creek Canyon Pipeline 5,000 5,000

2 Option 5 - East Canyon Pipeline 8,400 12,100

Total Developed 13,400 17,100

Figure ES-1 shows a recommended timeline for implementing the preferred plan. As shown in 

the figure, the Lost Creek Canyon Pipeline project would meet M&I needs in the immediate and 

near future with the East Canyon Pipeline project meeting later needs. The figure also shows a 

“transition” or “over-lap” period when both projects could meet growth needs in the Basin at the 

same time. This would likely occur as the Lost Creek Canyon Pipeline project water is near full 

utilization and the East Canyon Pipeline project has been constructed and is operational. Factors 

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Park City and Snyderville Basin Water Supply Study Special Report

which could govern the size of the over-lap would include how quickly the East Canyon Pipeline 

project can be constructed, the location of need within the Basin, and which water supply is the 

most marketable in terms of cost of water, proximity to growth areas, customer service, etc. 

Table ES-7 is a study summary which shows existing and projected needs, current water supply, 

and the preferred plan for meeting those projected needs. Future M&I Need (Acre-feet)

*Area to the left of the vertical line (2005) indicates M&I demands in excess of 

projected reliable supply. In order to meet the M&I demands, reserve capacity is 

being used. 

East Canyon Pipeline

12,100 Acre-feet

Lost Creek Canyon Pipeline

5,000 Acre-feet 

Projected Reliable Supply

(Includes additional groundwater development, 

Agriculture to M&I Conversion and Water Reuse) 

Transition 

Year 

2000 2010 2020 2030 2040 2050 

35,000 

30,000 

25,000 

20,000 

15,000 

10,000 

5,000 

0

Figure ES-1 

Preferred Plan Implementation 

*

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Park City and Snyderville Basin Water Supply Study Special Report

TABLE ES-7 

Study Summary

Units: Acre-Feet per Year 

Existing and Projected Needs 2001 2030 2050 

Population 23,900 64,300 86,300

Calculated M&I Demand 9,800 25,300 32,000

 Water conservation 0 (2,300) (5,000)

Adjusted M&I Demand 9,800 23,000 27,000

 Minimum in-stream flow/wastewater dilution requirement 0 1,100 1,600

 Mine tunnel concerns – mine collapse, water quality 0 2,000 2,000

Projected M&I Demand 9,800 26,100 30,600

Calculated Current Supplies 14,000 14,000 14,000

 Lost Creek Canyon project 0 1,600 1,600

 Jordanelle Special Service District imports 0 1,000 1,000

 Increased groundwater development 0 200 300

 Future agricultural conversions 0 400 500

 Reserve Capacity (4,200) (6,500) (7,500)

Projected Reliable Supply 9,800 10,700 9,900

Projected Future M&I Needs (Future Development) 0 15,400 20,700

 Future Water Reuse (Developed by Others) 0 2,000 3,600

Projected Additional M&I Needs (Preferred Plan) 0 13,400 17,100

Preferred Plan 

 Lost Creek Canyon Pipeline -- 5,000 5,000

 East Canyon Pipeline -- 8,400 12,100

Total Future Development -- 13,400 17,100

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