Crabtree Group, Inc. July 31, Civil Engineering. Land Planning. 325 D. Street P.O. Box 924 Salida, CO 81201

Transcription

1 Crabtree Group, Inc. Civil Engineering & Land Planning 325 D. Street P.O. Box 924 Salida, CO Phone: (719) FAX (719) Cell: (719) Water & Sewer Systems Evaluation & Planning Study for the Town of Poncha Springs, CO July 31, Page 1 of 107

2 TABLE OF CONTENTS TABLE OF CONTENTS... 2 ABBREVIATIONS... 4 EXECUTIVE SUMMARY... 5 INTRODUCTION... 9 GEOGRAPHICAL & TIMELINE SCOPE...9 PLANNING SCOPE...9 TECHNICAL SCOPE...10 FINANCIAL SCOPE...11 PLANNING & FORECASTING DEMOGRAPHIC DATA...11 HISTORICAL UTILITY DEMAND...14 GEOGRAPHIC DATA...24 ANALYSIS WATER INFRASTRUCTURE...27 WATER SYSTEM ANALYSIS...27 POTABLE WATER STORAGE...41 RAW WATER SOURCES...47 WATER TREATMENT...55 WASTEWATER INFRASTRUCTURE...56 NEW WASTEWATER TECHNOLOGIES...63 FRIEND RANCH PACKAGE TREATMENT PLANT...70 WATER RATES STRUCTURE ANALYSIS TYPES OF USAGE RATE STRUCTURES...71 RATE STRUCTURE COMPARISONS...72 USAGE RATE STRUCTURE RECOMMENDATIONS...73 WATER SYSTEM CONNECTION FEES...73 CONSERVATION VALUES AND POLICIES STUDY RECOMMENDATIONS WATER RECOMMENDATIONS...77 WASTEWATER RECOMMENDATIONS...80 Page 2 of 107

3 APPENDICES APPENDIX A: STUDY AREA & GROWTH BOUNDARY MAP...85 APPENDIX B: PROPOSED WATER ZONE MAP...87 APPENDIX C: WHEELER & ASSOCIATES LETTER...89 APPENDIX D: PONCHA-SALIDA WASTEWATER AGREEMENT...95 Page 3 of 107

4 ABBREVIATIONS AWWA American Water Works Association BLM Bureau of Land Management CDPHE Colorado Department of Public Health & Environment CML Colorado Municipal League fps Feet per second ISO Insurance Services Office gpd gallons per day gpcd metered gallons per capita per day metered through customer meters gpcd total gallons per capita per day metered by calibrated municipal well meters gpcd gallons per capita per day gphd gallons per household per day gpm gallons per minute m metered data MBR Membrane Bioreactor MWR Minimum Water Requirement NFF needed fire flow NR No specific Reference TSS Ten States Standards, Total Suspended Solids U.S.G.S. United States Geographical Survey The results of this analysis are for general planning purposes only and should not be used as design information or information to specify new equipment or infrastructure. This information should only be used to provide general planning guidance. Any new equipment, infrastructure improvement or modification should be analyzed and designed in detail by a qualified engineering firm. Page 4 of 107

5 EXECUTIVE SUMMARY The Water & Sewer Systems Evaluation & Planning Study was commissioned by the Town Board for Poncha Springs to provide an evaluation of the current water & sewer capacity and performance and to provide a planning baseline for future growth within the Town s growth boundary. The proposed Friend Ranch Golf Community was also included in the study area. Growth The Town has experienced a rapid growth in recent years with population increasing 16% and households increasing 15% on a per year average over a five year period. Vacant housing has increased from 11% to 17.5% over the same period indicating an increasing number of part time and transient residents, which are not included in population and household figures. If current growth rates are sustained, the estimated 25-year build-out population of the 5000-acre Growth Area is 6931 single-family residential units at an average density of 1.38 acres per unit and an estimated population of 15,000 people at 2.3 persons per household. Water Use Statistics The Town produced approximately 25,000,000 gallons of treated water in The average water use was 148 gpcd including unaccounted water, which compares favorably with most municipalities. The Town should strive to reduce this average water use to 125 gpcd over the next 5 10 years. Unaccountable water usage was 26.5% which is very high when compared to an average of 12% across 63 water systems in Colorado. Reducing the unaccountable water use to 10% or less should be a high priority. Water System Infrastructure The Town operates its own water system, which obtains its raw water from three ground water wells. A fourth well has been drilled and is not yet in production. The water system has 260,000 gallons of gross storage capacity. A computer control system is used to control tank levels and well pumps. Treatment methods are hypo-chlorination for Well #3 and gas chlorination for Wells #1 & #2 augmented with corrosion control chemicals for lead/copper. Chlorine contact time is provided by contact chambers at each treatment site prior to direct injection of treated water into the distribution mains. Tank retention time is Page 5 of 107

6 managed by allowing the tank levels to fluctuate during short periods of time each day. Distribution mains are primarily 6 diameter with some 8 diameter mains and a portion of 10 trunk line from the storage tank to an area near the South Arkansas River. The system branches into two distinct distribution branches just north of the river with the branches separated by U.S. Highway 285. Water System Modeling Results and Recommendations A computer model (EPANET software) of the existing water system was developed to assess the overall system performance. Results show that the current service area has sufficient static pressures ranging from 53 psi to 110 psi. Domestic flow demands are met throughout the system without significant pressure losses. The model predicts shortfalls in potential fire flow capacity due to a lack of looped system mains. A loop connection between the 8- inch branch on the south side of Highway 50 and the Well #3 location is highly recommended. The computer model also indicates that fire flow in some areas is being limited by main size. It is recommended that the Town modify its design standards to a minimum 8-inch diameter distribution main. Modeling and analysis also shows that the existing net water storage capacity is insufficient for fire flow requirements above 1500 gpm. Given the potential future growth and increasing commercial fire flow requirements it is recommended that additional water storage be considered on the north or east side of the Town and connected as part of the branch looping using a 12 inch diameter trunk main. For future storage facilities, treated water should be pumped in a dedicated feed line to the storage tank to improve contact time, reduce tank retention time, and allow for water blending if necessary. If the Town is considering a transition from a contract water operator to in-house operators it is recommended that gas chlorination on Well #1 & #2 be converted to hypo-chlorination using either liquid or tablets to reduce training and safety equipment cost. Water Service Area Growth An analysis of the study area shows that five distinct water zones would be required to service the Growth Area including the Friend Page 6 of 107

7 Ranch. Preliminary modeling indicates that all zones be interconnected with a 12-inch trunk main using pressure reducing valve stations for zone pressure control and looped mains to the trunk line. Additional water storage at an elevation of 8240 feet would be required to serve pressure zones 3-5. Storage capacity would need to be sized for the domestic demand plus the maximum fire demand. A minimum 500,000-gallon tank would be required if the fire demand is limited to 1500 gpm. If the fire demand were 3000 gpm, a 750,000-gallon tank would be required. Water Rights Analysis by the Town Water Engineer & Water Attorney has shown that raw water rights currently exist for approximately 490 singlefamily unit taps. Currently approximately 295 of these taps are in use or 50% of the total tap capacity. It is our understanding from discussions with Town staff that the Friend Ranch Project would annex into the Town and provide water rights to the Town for augmentation of its water usage. According to the Upper Arkansas Water Conservancy District, depletions on the South Arkansas River are a significant concern. Package wastewater plant(s) should be explored as a method to reduce 100% replacement of depletions on the South Arkansas River. The process for analysis and approval of a new wastewater treatment plant is under the jurisdiction of the Colorado Department of Public Health and Environment. Special Water Topics & Recommendations The EPA adopted a Radionuclides Rule December 7, The purpose of the rule was to reduce exposure to radionuclides in drinking water to reduce cancer. The combined radium 226/228 allowable is 5 pic/l, averaged across four consecutive quarters of water tests. The highest well annual average was 4 pic/l, the highest result in a single quarter was 10 pic/l for well number 3. The town currently meets the radionuclides rule for combined radium. The physical and chemical processes that cause radium peaks and variations are not well understood. Combined with the extremely high costs of radium removal, it is prudent to consider options to mitigate the risk of exceeding regulatory standards at some future date. Page 7 of 107

8 Sewer Capacity The town s wastewater is currently served via a 10 wastewater trunk line to the Salida Wastewater Plant. The Poncha Springs Salida Wastewater agreement limits the wastewater flow to a peak daily monthly average flow of 271,700 gallons per day. This flow was based on 1130 EQR s. The current peak daily monthly average flow on a per household basis limits the total number of actual EQR s to 928 serviceable at current peak month flows. Approximately 637 taps are currently available and 271 taps are in use. It is recommended that consideration be given to future wastewater expansion utilizing wastewater treatment with return flows to the South Arkansas River Tributary using Membrane package treatment plant technology. If a package plant permit is not achievable the Town should begin negotiations with Salida for additional capacity and a study to determine the optimum location for a second sewer truck line. Route options should be studied carefully taking into consideration projected growth service areas and minimization of infiltration risk. Rate Structures The Town s service water rates are on the high end compared to several other Colorado town and city rate structures; but the rate structure compares favorably to similar sized small systems. No change is recommended in the current water service rate. Due to economy of scale, as the water system grows the water rate structure can be modified to reduce the basic monthly service fee while increasing the block rate structure fees for higher use customers. A water tap rate analysis shows the current tap rate structure is sufficient, with raw water costs being $3, of the $5, tap fee. It is recommended that the tap fee be split into a water development fee of $ due at lot final plat and a $2, water infrastructure fee due at tap connection to a structure. Sewer rates appear to be sufficient for the current infrastructure replacement cost and service costs. If the Town develops its own treatment capacity a rate study would be required to determine tap fees for the area serviced by the plant. SUMMARY OF STUDY RECOMMENDATIONS Please see page 77 Study Recommendations. Page 8 of 107

9 INTRODUCTION This study was commissioned by the Poncha Springs Town Board to provide an engineering evaluation & planning study of the Town s water and sewer system; and to develop a set of decision planning tools based on current and projected service demands. GEOGRAPHICAL & TIMELINE SCOPE The geographical scope of the study (Growth Area) includes the incorporated area of the Town, the Town s growth boundary and the Friend Ranch Sketch Plan area. A map of the geographical study area is provided in Appendix A. The scope of the timeline for the study is current to 25 years into the future. Projections are provided in five-year increments. PLANNING SCOPE The planning scope of the study evaluates the potential zoning and density of the individual properties within the defined geographical area, topography, historical service demand data and demographic trends to forecast future service demands. Property and topography studies provide information such as: Estimates of service demand of the total Growth Area. Specific estimates of service for each large property parcel. Only parcels over 10 acres in size are evaluated in this study outside existing Town boundaries. This limit was chosen because it is unlikely that smaller parcels with existing homes will be redeveloped outside of current Town limits in the Growth Area within the timeline of the study in significant quantity to effect study results. Also these smaller parcels would have an insignificant effect on the outcome of the study. Demographic trends provide information such as: Population growth. Persons per household. Vacancy rates for households. Historical service demand data provides information such as: Average per capita service demands and demand trends. Average per household service demands and demand trends. Page 9 of 107

10 Use trends driven by improved water conservation. Effects of drought years. Effects of tiered water rate structures and water rate levels. Infiltration and leakage impacts. Peaking factors by season. TECHNICAL SCOPE The technical scope of the study evaluates the current infrastructure s ability to meet current service and public safety demands and uses the planning projections of the study to analyze the impact of future growth on the water and sewer systems. Technical concepts are developed to project capital improvements needed to meet future service demands. Water Infrastructure is evaluated to analyze technical standards such as: Storage Capacity. Well Pumping or Surface Water Extraction. Water Rights Augmentation. Water Treatment. Pressure Zones. High Pressure Mains. Fire Flow. System Redundancy/Looping. Water Utility Standards Recommendations. Sewer Infrastructure is evaluated to analyze technical standards such as: Poncha-Salida Wastewater Agreement Capacity. Poncha-Salida Total and Remaining Trunk Line Capacity. Potential advantages of small to medium package sewer plants for wastewater expansion and remote service areas. Water Augmentation and Depletion Replacement Considerations. Potential Sewer Lift Zones. Sewer Utility Standards Recommendations. Page 10 of 107

11 FINANCIAL SCOPE The financial scope of the study provides a set of rough order of magnitude estimates for major capital improvement items and evaluates the current rate structure against projected future costs of system expansion. Financial analysis will provide information such as: Comparisons of service rate structures with other cities and towns. Service rate & Development Fee Structure Recommendations. PLANNING & FORECASTING This report section summarizes the results of the analysis of demographic data, land parcel data, historical utility data and state demographic data related to the planning and forecasting of water and sewer service within current Town limits, the proposed Town growth boundary and the proposed Friend Ranch Golf Community. DEMOGRAPHIC DATA Demographic data was collected from U.S. Census and State records to provide historical data to be used in projecting future growth in the projected Town service area. HOME AND POPULATION TRENDS Population has increased in the Town an average of 16% per year over a five year period, and the number of homes has increased 15% per year over the same five year period as shown in Figure 1. This is a high growth rate and an indication that service infrastructure will require careful attention regarding both capacity and financial cash flow to support capacity expansion. Additionally, the potential of a request to annex 600 acres of the Friend Ranch for a golf course community adds an additional growth factor. The State demographer projects a 2.2% annual growth rate for the Central Mountain Area for the next ten years and a 1.7% annual growth rate for the period of 2010 to The Central Mountain Page 11 of 107

12 Area annual growth rate projections do not appear to be a good fit for the Town s expected growth rate. HOME & POPULATION TRENDS POPULATION INCREASED 16% ON AVERAGE HOUSEHOLDS INCREASED 15% ON AVERAGE HOMES POPULATION FIGURE 1 VACANCY RATES AND PERSONS PER HOUSEHOLD Rural Mountain Colorado Communities have been experiencing a set of demographic trends that include: An increasing number of second homes and vacation homes. An increasing number of retirees without children. Higher costs for land and homes in many areas, contributing to a strong need for affordable housing. The Town of Poncha Springs shows some of these trends in their demographic data. The Town has been progressive in encouraging affordable and multi-family housing which has helped to maintain a moderate level of families. However the data as presented in Figure 2 shows an increase in vacancy rates indicating a growth in second homes and vacation homes as an overall percentage of the total. Page 12 of 107

13 20.00 HOUSING DEMOGRAPHICS PERSONS VACANCY RATES HAVE INCREASED 6.6% IN THE LAST 5 YEARS PERSONS PER HOUSEHOLD IS RELATIVELY STABLE VACANCY PERS/HOUSE FIGURE 2 The data in Figure 2 also indicates a slight increase in persons per household (most likely due to the affordable housing efforts of the Town) yet the average household size of 2.3 persons/household, is 5% below the State average of 2.43 and 12% below the U.S. average of Vacant housing (any housing at which no persons are claiming full time residency) at 17.53% is 20% higher than the State average of 8%. The vacant housing trend for the Town shows a 14.5% increase in the period of 1999 to Since vacant homes are usually occupied during peak demand periods, and utility systems must be sized for peak demand, thus non-resident occupancy peaks are a factor in utility capacity analysis. Using only population figures for projecting utility peak demand does not factor in the effect of vacant housing demands. Also, population projections may not account for or factor the commercial demand within the Town. Growth of water taps is another method of forecasting future demand increases. Figure 3 shows the past five-year growth trend in residential and commercial water taps. Residential taps have grown at a 9% annual average and commercial taps have grown at an 11% annual average. Given that each household is 2.3 persons a 9% growth in Page 13 of 107

14 residential taps equates to a population growth of approximately 20%, which verifies some effects of vacant housing and other factors not accounted for in population figures. 250 WATER TAP GROWTH 200 Residential Tap Growth = 9% TOTAL TAPS Commercial Tap Growth = 13% TOTAL RES TOTAL COMM FIGURE 3 DEMOGRAPHIC DATA SUMMARY The demographics show a high growth rate in both population and tap growth. The complexities of vacant homes and commercial growth are not captured by population statistics and should be closely monitored. If population equivalent tap growth (taps x persons per household) exceeds population growth, tap growth should be used as the primary growth factor. In the current case, tap growth is the higher figure and its rate of growth should be given more weight in forecasting future demand. A 10-15% annual growth rate in utility demand could be a realistic assumption for the Town of Poncha Springs over the next 25 years. HISTORICAL UTILITY DEMAND Utility records for the past five years provide a snapshot of actual utility demands that can be used to derive unit demand profiles on a per-capita and per-household basis. These unit demand profiles can then be used to forecast future utility demands by multiplying unit demands by projected growth rates. This section analyzes the historical demand in the Town to develop Town-unique demand Page 14 of 107

15 profiles that are compared in later technical analysis sections to national standards. WATER DEMAND Water demand (as shown in Figure 4) has decreased 40% per household over the last five-year period. Conservation measures taken by the Town in the form of leak repairs, water rate increases and water restrictions during the irrigation season have significantly reduced water demand on a per-person or per-household basis, resulting in an overall decrease in demand despite the addition of 56 new residential taps and 9 new commercial taps during the same period. The most recent data estimate of the Town s present water demand is an annualized pumped average of 282 gallons per household per day, or gallons per person HISTORICAL WATER USE GALLONS gpcd metered gpcd total gphd FIGURE 4 The pumped water demand of gpcd is near the average for the climate area and compares favorably with the data in Figure 5. The Poncha Springs and Salida data in the figure is for the year 2005, other cities data are for the year Because of the 2002 drought some further conservation improvements have most likely Page 15 of 107

16 been accomplished for these cities. Buena Vista did not provide data. Single Family Residential Daily per capita Water Consumption Gallons per day Poncha Springs Salida Buena Vista Round Mountain Fort Collins Loveland Estes Park Denver Tucson AZ San Antonio TX Albuquerque Boulder El Paso Grand Junction Highlands Ranch Las Vegas Mesa Phoenix Scottsdale Tempe FIGURE 5 It is recommended that a Town goal be set to accomplish a reduction in water use to 125 gpcd over the next five years as a method of managing cost and creating more tap capacity with current water rights. This proposed 18.4% reduction could increase tap capacity by approximately 90 taps. UNACCOUNTED WATER The 2005 average water usage as measured by commercial and residential service meters (metered demand) was gallons per person or gallons per household. The water usage during the same period, as measured by the Town s well pump meters (pumped demand), was gallons per person or 282 gallons per household per day, which indicates a 26.7% water loss (or discrepancy) in the system. A typical design number (Civil Engineering Reference Manual, Ninth Edition) used for system water loss is 10%. Page 16 of 107

17 The well meters have been checked and calibrated so there is some indication that either leaks or faulty service meters may be contributing to the discrepancy. The Town is replacing all of its service meters in 2006 which will eliminate one of the potential contributors and may solve the discrepancy. Water demand predictions may need to be adjusted upon resolution of this discrepancy. Unaccounted For Water as % of Total Raw Water Extracted SYSTEM AVERAGE = 12% % of Raw Water Extracted Poncha Springs Buena Vista Gunnison Canon City Kiowa Boulder Denver La Junta Grand Junction Highlands Ranch Steamboat Springs Sterling Palmer Lake Monument Woodland Park FIGURE 6A Figure 6A shows unaccountable water data for several towns and cities (Water & Wastewater, Utility Charges and Practices In Colorado, CML). The unaccountable water average across 63 reporting systems in Colorado was 12%. Some cities such as Denver have reduced their unaccountable water losses by 3X in recent years by dedicating resources to finding and fixing leaks. The Town should continue to reduce unaccountable water until the rate reaches 12% on a short-term basis and 5% on a longer term. Figure 6B is a graph showing well-pump meter data, billed meter data, water loss and average water loss. The water loss does not appear to track water volume, yet shows some variation from approximately 500,000 gallons to 1,000,000 gallons loss per month. Page 17 of 107

18 New water meters were installed in mid May 2006 and as of yet there is no indication of a reduction in water loss. Several months of data will be required to effectively analyze whether the new customer water meters are having a positive effect on water loss reduction. Water leakage should remain relatively constant if the pressure is constant. An area of the water system that sees significant pressure variation is the area near the wells where pressure spikes occur during well pumping. A leak in these areas could explain the water loss variation. WATER LOSS ANALYSIS 5,000 4,500 4,000 3,500 GALLONS x 1,000 3,000 2,500 2,000 1,500 1, Jan- 05 Feb- 05 Mar- 05 Apr- 05 May- 05 Jun- 05 Jul- 05 Aug- 05 Sep- 05 Oct- 05 Nov- 05 Dec- 05 Jan- 06 Feb- 06 Mar- 06 Apr- 06 May- 06 PUMPED BILLED LOSS AVG. FIGURE 6B In an attempt to determine a correlation between water loss and well pumping, the water loss was plotted with water pumping and the change in water pumping as shown in Figure 6C. Some correlation is evident between the rate of pumping change and the loss change. Clearly in the period of Jan-06 to Apr-06 when the rate of change of pumping was stable, the water loss was also stable. Page 18 of 107

19 WATER LOSS CORRELATION WELL #2 2,500 GALLONS (THOUSANDS) 2,000 1,500 1, ,000 Jul-05 Jun-05 May-05 Apr-05 Mar-05 Feb-05 Jan-05 May-06 Apr-06 Mar-06 Feb-06 Jan-06 Dec-05 Nov-05 Oct-05 Sep-05 Aug-05 LOSS WELL #1 & #2 D-WELL #1 & #2 FIGURE 6C This data provides some indication that the water loss is contributable to water leakage in the area of Well #1 and #2 or the main nearby. This area is subject to pressure variations that could explain the loss variation. A similar analysis was performed for Well #3 and no correlation was evident. It is recommended that a leak test be performed in the subject area. Water Conservation Factors. Despite recent significant improvements in water conservation made by the Town, (as noted in Figure 4) the Town s average annual rate of water usage (148 gpcd) still exceeds National averages of gpcd (Civil Engineering Reference Manual Ninth Edition). A focused program using the AWWA water audit methods as outlined in Figure 7 is recommended to reduce overall per capita water use. Reduction of water losses such as the 26.5% unaccounted water is the lowest cost approach to expanding the water capacity of the system. Page 19 of 107

20 System Input Volume (corrected for known errors) Authorized Consumption Water Losses Billed Authorized Consumption Unbilled Authorized Consumption Apparent Losses Real Losses Billed Metered Consumption (including water exported) Billed Unmetered Consumption Unbilled Metered Consumption Unbilled Unmetered Consumption Unauthorized Consumption Customer Metering Inaccuracies Data Handling Errors Leakage on Transmission and Distribution Mains Leakage and Overflows at Utility s Storage Tanks Leakage on Service Connections up to point of Customer metering Revenue Water Non- Revenue Water (NRW) FIGURE 7 AWWA water audit software is available and is recommended for use in managing a water loss reduction program. A copy of the software has been provided as part of this study. In addition a Leak Detection Handbook has been provided to aid with leak detection procedures. Additional or continued conservation measures (such as more efficient use of the Town s irrigation water rights) could be expected to bring the average usage rate within or below National averages. At this time, the existing yearly average pumped demand of 148 gpcd, or 282 gallons per household per day will be used as the present and projected water demand PEAKING FACTOR Another critical demand factor for a water system is peak demand. Water demand varies by season and the system must be designed to handle the peak demand day or month. Figure 8 shows the water and sewer demand curve by month for the 2005 year. The peak monthly demand occurred in June and was 163% of the average yearly demand. A monthly water peaking factor of 1.63 will be used in system sizing calculations. For example if the Page 20 of 107

21 average annual daily demand of a household is 282 gallons per household per day, the summer peak average monthly demand would be 460 gallons per household per day. 4,000 WATER & SEWER DEMAND BY MONTH 3,500 3,000 GALLONS x 1,000 2,500 2,000 1,500 1, JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC M-WATER 1,685 1,260 1,305 1,506 2,604 3,400 3,054 3,079 2,696 1,471 1,440 1,535 M-SEWER ,782 2, , ,008 FIGURE 8 Figure 8 indicates an irrigation season beginning in late April to early May and continuing through September. In the non-irrigation season the average system use was 1.5 million gallons per month. This data indicates the average household is using approximately 26,000 gallons of potable water per irrigation season or 175 gphd for outside irrigation, not including irrigation that occurs from the Town ditch system. This indicates a potential avenue for further conservation of potable water. (The sewer demand curve shown on Figure 8 will be discussed in the sewer section below.) SEWER DEMAND Sewer demand data was obtained from the Poncha Springs sewer meter installed just east of Poncha Springs Lane on Highway 50. Figure 9 shows sewer demand for a five-year period. As would be expected, as water use was curtailed by conservation measures, the sewer demand was similarly reduced. Page 21 of 107

22 700.0 SEWER HISTORICAL USE % REDUCTION IN PER CAPITA SEWER IN FOUR YEARS GALLONS PER DAY gpcd gphd FIGURE 9 The data in Figure 8 shows an increase for sewer demand in the summer months. Most sewer systems do show summer peaks due to infiltration. Figure 8 shows water and sewer demand by month for the year The peak demand occurred in July and was 170% of the average monthly demand. Sewer infiltration has been a subject of concern for several years and a significant amount of investigation and work has been performed by the Town to reduce the infiltration rate on sewer mains. Figure 10 shows water and sewer demand over the last five-year period and indicates that these conservation efforts have been quite effective. At present, a monthly sewer peaking factor of 1.70 will be used in system sizing calculations, though that number may be reduced even further by ongoing conservation measures. Page 22 of 107

23 SEWER & WATER COMPARISON 80% Reduction in Per Capita Sewer Over 4 Years GALLONS PER DAY % Reduction in Per Capita Water Use Over 4 Years sewer gpcd Total-water gpcd FIGURE 10 Overall, the level of sewer demand on a per capita or per household basis appears to be within normal ranges even with the laterals infiltration that has been identified by camera inspections. National averages have ranges of gpcd (Civil Engineering Handbook, Ninth Edition). For the purposes of this study a sewer demand of 117 gphd and 63 gpcd will be used to forecast future demand requirements consistent with the present use rates. The average demand will be multiplied by the peaking factor for analysis of the Wastewater Agreement Capacity. HISTORICAL UTILITY DEMAND SUMMARY Based on analysis of the historical utility data for the purposes of this study the demand values that will be used are: Water Demand = 148 gpcd or 282 gphd Water Monthly Peak Demand Factor = 1.63 Water Daily Peak Demand Factor = 1.5 [Civil Engineering Reference Manual] Sewer Demand = 63 gpcd or 117 gphd Sewer Monthly Peak Demand Factor = 1.70 Page 23 of 107

24 GEOGRAPHIC DATA Geographic data such as land parcels and topography were analyzed to provide information regarding total utility demand by area, density and zoning. Topography was analyzed to establish potential pressure and pumping utility zones. Information from the County Assessor s database was used for parcels and U.S.G.S. files were used for topography. See Appendix A for the parcel map. PARCEL ANALYSIS An analysis of parcels within the specified geographical area of the study (Growth Area) was performed using the Chaffee County Assessor s database. All parcels within the Town s growth boundary, which is bounded on the west by CR 250, on the east by CR 146 on the north by CR 140 and the south by the U.S. Forest and BLM as well as the proposed Friend Ranch annexation outside of the Town growth boundary were listed and analyzed for parcel size, potential zoning use, and potential build-out density. Existing vacant lots within the Town limits were also included in the analysis. The analysis provides the demand potential for the Growth Area which may be helpful in planning for future water & sewer trunk line and plant capacity requirements. Table 1 is a summary of the analysis of the parcels using the best estimate build-out density to approximate water and sewer demand. The study area is approximately 5011 acres, which includes incorporated areas, the growth boundary and the Friend Ranch. For the purposes of this analysis, projected commercial lots were considered to be equal to 3 residential demand units. Projected lot densities are based on the parcel s topography, location and likely development type. There is no exact science for predicting density levels as markets, regulations and business cases vary over time and determine what type of development will occur. Even though these assumptions for individual parcels may be significantly different than actual future development, for the purposes of this study, the density analysis should produce a reasonable assumption for the overall utility demand in the study area. Page 24 of 107

25 PROPERTY OWNER SIZE DENSITY UNITS ZONING WATER DEMAND STORAGE DEMAND SEWER DEMAND (acres) (units/acre) (gpd) (gal) (gpd) FRIEND RANCH RES 126, ,887 66,573 FRIEND RANCH 5 COMM 3,345 3,345 1,755 GLENDA SCANGA RES 20,182 20,182 10,589 DEAN ROBERTS RES 63,979 63,979 33,567 DEAN ROBERTS COMM 26,760 26,760 14,040 HOLMAN ASPEN RES 33,227 33,227 17,433 HOOVER RANCH RES 35,903 35,903 18,837 HOOVER RANCH COMM 13,380 13,380 7,020 WOOD RES 14,673 14,673 7,699 LINSDAY RES 7,114 7,114 3,732 ANDREAS RES 8,920 8,920 4,680 DENVER RIO GRAND RES 12,265 12,265 6,435 CROSSROADS RES 5,530 5,530 2,902 PONCHA ESTATES 25 1 RES PONCHA ESTATES 1 COMM PONCHA SPRINGS na CITY OF SALIDA RES 16,168 16,168 8, COMM 8,920 8,920 4,680 PONCHA MTN PART RES 11,886 11,886 6, COM 26,760 26,760 4,680 FARROW RES 60,210 60,210 31,590 BENDER RES 37,955 37,955 19,913 LITTLE RIVER PHASE I 51 RES 11,373 11,373 5,967 LITTLE RIVER PHASE II 21 RES 4,683 4,683 2,457 LITTLE RIVER STAGE IIA RES 15,610 15,610 8,190 LITTLE RIVER STAGE IIB RES 15,610 15,610 8,190 KARASA RES 7,805 7,805 4,095 CANYONS 20 RES 4,460 4,460 2,340 BAGWELL RES 7,805 7,805 4, COM 13,380 13,380 7,020 MOLTZ RES 15,253 15,253 8, COMM 13,380 13,380 7,020 FARROW COMM 6,958 6,958 3,650 HUTCHINSON RES 40,140 40,140 21,060 MASSEY RES 5,575 5,575 2,925 PARADISO RES 4,460 4,460 2,340 ROHR RES 4,460 4,460 2,340 SARTORIUS RES 3,211 3,211 1,685 GINTHER COMM 13,848 13,848 7,266 DETTWILLER RES 6,422 6,422 3,370 BACA RES 20,070 20,070 10,530 NIXON RES 4,460 4,460 2,340 BACA RES 6,556 6,556 3,440 ADAMS RES 26,760 26,760 14,040 Table 1 Parcel Analysis Page 25 of 107

26 PROPERTY OWNER SIZE DENSITY UNITS ZONING WATER DEMAND STORAGE DEMAND SEWER DEMAND (acres) (units/acre) (gpd) (gal) (gpd) SCANGA RES 71,761 71,761 37,651 FURTON RES 22,077 22,077 11,583 RYFF RES 61,102 61,102 32,058 SANCHEZ RES 49,506 49,506 25,974 ADAMS RES 39,248 39,248 20,592 LOWRY RES 26,760 26,760 14, COMM 11,373 11,373 5,967 LAND W LLC RES 55,973 55,973 29, COM 16,725 16,725 8,775 PONCHA RETAIL COMM 6,690 6,690 3,510 UTE DEVELOPMENT COMM 201, , ,651 GUCCIONE RES 100, ,707 52,837 PAYNE RES 35,680 35,680 18,720 PALLARO RES 35,680 35,680 18,720 RICHARDSON RES 26,760 26,760 14, COMM 12,711 12,711 6,669 FRANCIS RES 124, ,657 65,403 MEHOS RES 54,858 54,858 28,782 THOMAS DAIRY RES 17,840 17,840 9,360 VOYLES RES 3,122 3,122 1,638 EXISTING TOWN LOTS 135 RES 30,105 30,105 15,795 EXISTING TOWN LOTS 20 COMM 13,380 13,380 7,020 house acres average density unit equiv. gallons /day gallons avg. gallons /day EXISTING TOWN LOTS NA NA ,485 43,485 22,815 FRIEND RANCH , ,232 68,328 GROWTH AREA 4,421 6,362 1,631,602 1,631, ,565 TOTALS 5, ,931 1,805,542 1,805, ,708 Table 1 Parcel Analysis (continued) The parcel analysis is provided as a spreadsheet so assumptions and changes can be analyzed as conditions change in the future. PARCEL ANALYSIS SUMMARY Using current demand rates on a per-household basis, the total study area is projected to increase water demand to 1,805,000 gallons per day average daily treatment capacity and domestic storage capacity, as well as 937,000 gallons per day for wastewater treatment. Currently the Town treats a daily average of 64,000 gallons of water and produces a daily average of 35,000 gallons of wastewater. At 5% per year, the full build out of the Growth Area Page 26 of 107

27 ANALYSIS would take approximately 68 years to reach a build-out population of 15,000. At a 15% growth rate, the build-out would occur in 25 years. WATER INFRASTRUCTURE The existing water and sewer system as-built features were obtained from best available Town records which appear to be reliable. Existing Water System. The existing Town water system supply consists of 3 wells and two storage tanks with gross volumes of 160,000 gallons and 100,000 gallons located South of Town on Hot Springs Road at elevation The distribution system consists of mostly 8 inch and 6 inch diameter mains with a single 10 trunk line from the storage tanks for a portion of the distance to the river. Wells #1 & #2 are located on the south side of the South Arkansas River and share a treatment facility that uses chlorine gas, with a secondary treatment for lead and copper. Contact time is provided by two buried contact chambers and treated water is pumped directly into the main system. Well #3 is located in the Poncha Springs Industrial Park and uses a hypo-chlorination primary treatment with a secondary lead and copper treatment. A contact chamber is used for contact time and treated water is pumped directly into the distribution mains. WATER SYSTEM ANALYSIS The key factors for a water system design, operation and maintenance are: Water Quality that meets State and Federal Standards. Water supply, treatment and storage capacity to meet domestic demand. Water storage capacity to meet Fire Flows per the adopted fire code. Expansion capability to accommodate growth. Page 27 of 107

28 Maintainability of capital assets to assure reliable service at the lowest cost. Operational configuration to minimize cost, liability, and maximize reliability. WATER PRESSURE ZONES The variation in elevation across the service area requires analysis to determine what system elements will be required for distribution of water. Analysis of topography is used to determine if one or more pressure zones are required. Water pressure is typically created and maintained by pumping water to a storage tank at an elevation above the service area sufficient to create static pressure head (potential energy). The static water pressure in a system varies by the difference in elevation between the storage tank and a service water tap elevation. One hundred feet in elevation change equates to a 42- psi static pressure change. For example, if the storage tank is at 8200 feet and the water tap elevation is at 8100 feet, the static water pressure would be approximately 42 psi. The preferred static water pressure range in a water system according to State recommendations is 35 to 60 psi. This narrow recommended pressure range allows for only 58 feet of vertical elevation variation and severely limits the area serviceable by a pressure zone in mountainous terrain. Many mountain towns have wider ranges with pressures from 35 to 110 psi. If homes experience problems with the higher range of pressure, house pressure regulators can be installed for a minimal cost by the homeowner. The current pressure range in the Poncha Springs system is approximately 50 to 96 psi. One consideration for higher-pressure mains is leakage loss. The higher the pressure, the more water loss per leak area. The analysis of potential water pressure zones in this study was based on a minimum static pressure of 40 psi and a maximum static pressure of 110 psi at full storage tank conditions. This wider pressure range expands the service area of a pressure zone. The 70-psi allowable variation in water pressure within a zone translates to a maximum 160 feet of vertical elevation difference across the zone. The system static pressure will also vary approximately 8 psi from full tank to empty tank conditions for a tank with 18 feet of vertical water column height at full level. The maximum recommended variation due to storage tank level is 35 psi or 80 feet of water column per State standards. This topography analysis uses the current water service area as the base zone, which is identified as Zone #2. The base zone size Page 28 of 107

29 covers as large an area as possible with a 160 foot or less elevation difference. Then additional zones are determined as necessary within the study area, with each zone having a maximum 160-foot elevation difference from its lowest point to its highest point. A map of the proposed water zones is provided in Appendix B. The result shows that five zones could be required to serve the study area which includes the full Growth Area including the proposed Friend Ranch. The map shows the five pressure zones, each with a160-foot elevation change within a zone. This planning analysis used readily available 40-foot contour U.S.G.S maps. For actual water main and PRV design a higher accuracy 2-foot contour mapping would be recommended. WATER ZONE STATIC PRESSURE SUPPLY AND CONTROL There are two possible approaches to providing pressure to the proposed zones. Each zone could have its own storage tank at the required elevation or all the zones can be connected by a central trunk distribution line and zones can share water storage facilities. The second approach is recommended because it provides a more cost-effective solution and also provides increased water supply redundancy to the system. Zone 2 is the existing Poncha Springs water service area that can be served without additional tank elevation or pressure reducing valves. Zone 1 is east of Town and has elevations below the existing zone. This zone can be served from the existing storage elevation using pressure-reducing valves to connect it to Zone 2 or a high-pressure trunk line. Zones 3-5 of the pressure zones mapped are at elevations above the maximum elevation serviceable by the existing water storage tanks for gravity service. Storage is required at a higher elevation to serve these zones. A single storage location at an elevation high enough to serve the highest zone (Zone 5 Friend Ranch) is also capable of servicing all of the lower Zones 1-4. This multi-zone service can be accomplished by connecting the zones using pressure-reducing valves and a high-pressure trunk line. To minimize pressure loss due to friction, trunk line sizes should be increased above typical main sizes to 12 inches. To maximize flow capacity the trunk line could be operated at pressures higher than the allowable service pressures, in which case the high-pressure Page 29 of 107

30 trunk line would be connected to service zone mains only by way of a pressure-reduction valves. Figure 11 shows a schematic diagram of 5 pressure zones interconnected using high-pressure mains, pressure-reducing valves and looped zones. The following summarizes the pressure zone concept in Figure 11: A 12 diameter high-pressure trunk connects all zones. This symbol represents a pressure-reducing valve that would reduce the pressure from the trunk line to an acceptable level for each zone. Zones 1 & 2 are served by both Tank #1 and Tank #2. Zones 3, 4 & 5 are served by Tank #2 (Friend Ranch Tank) and provide storage redundancy to Zones 1 & 2. Wells and treatment could be connected to the high pressure trunk line and serve all zones, or can be dedicated to a specific zone or tank. It is recommended that wells and treatment pump directly to storage and are not connected to mains or trunk lines. Page 30 of 107

31 ZONE ELEV.= 7241 ft. HIGH PRESSURE TRUNK LINE #2 ZONE 1 CURRENT ZONE ft. TANK #1 Full Elev ft. HIGH PRESSURE TRUNK LINE #1 ZONE 3 ZONE ft ft. ZONE 5 TANK #2 Full Elev ft. FIGURE 11 North 8048 ft. Page 31 of 107

32 DYNAMIC PRESSURE & FLOW ANALYSIS {CURRENT SYSTEM} This section analyzes the dynamic requirements and performance of the existing water system in a demand flow condition. The dynamic requirements of a water system can be subdivided into three basic categories: Domestic demand (household and small commercial demand) Fire Flow demand Industrial or Process demand In this case there are no known large industrial or process demands on the system, nor are any anticipated in the near future. Domestic demand includes all water use on the system for nonemergency purposes to include houses, commercial, landscape irrigation and other uses. This demand is regular and predictable as can be seen from the historic use data provided in earlier sections. Domestic demand drives system parameters such as: Raw water supply Treatment capacity Non-emergency storage supply Water quality requirements Domestic requirements which include: o Dynamic residual pressure 35 psi minimum o Continuous service Fire Flow demand are defined by adopted fire code requirements, are an order of magnitude greater than maximum peak domestic flow requirements and drives system parameters such as: Distribution line sizes Looping requirements Emergency (fire flow) dedicated water storage supply. Fire flow requirements per ISO standards which include: o 20-psi minimum residual pressure at the hydrant in use. o Residential Fire Flows for house separations of 10 feet or less is 1500 gpm. Page 32 of 107

33 o Residential Fire Flows for house separations of feet is 1000 gpm. o Residential Fire Flows for house separations of feet is 750 gpm. o Residential Fire Flows for separations greater than 100 feet is 500 gpm. o Commercial fire flow is determined by the formula: Q= 18F (A ft 2 ) 1/2 where F is a factor for construction type. o Fire flow for the Poncha Lumber Yard was calculated by the Chaffee County Fire Department to be: 3500 gpm. o ISO performed an inspection and fire flow tests on several hydrants in the Town in March The needed fire flows (NFF) were determined by ISO for these locations: Hwy 50 & Poncha Springs Ln gpm. 150 Pahlone 2250 gpm Hwy gpm. Alabama & Nickerson 1000 gpm. Ouray & Hwy gpm. Truman & Pinon 750 gpm. Chipeta & Tomichi 1250 gpm. o Fire flows must be maintained for: 2 hours for NFF< 3000 gpm 3 hours for flows 3000 gpm < NFF< 3500 gpm 4 hours for NFF > 4000 gpm Page 33 of 107

34 If there was not a requirement for fire flow, water distribution mains could be on the order of 3-4 lines in most cases because the low flow rates required for domestic use do not create significant pressure drops. Conversely, fire flow requirements drive distribution main sizes to on average 8 to 12 in main size for residential, commercial and small industrial areas. This is because high flow rates create large pressure drops that increase with velocity, thus larger pipe sizes are required to keep velocities in acceptable ranges to minimize pressure drop. A water model of the existing Poncha Springs water system was created to perform dynamic analysis on the water system. As with any model the accuracy depends on the quality of the input and the knowledge of actual as-built infrastructure. This model was constructed with the best available information and was validated to reasonable tolerances by field measurements provided by ISO testing. The purpose of the model is to evaluate the general performance of the system and to model potential improvements to the system for the evaluation of potential design concepts. The results of this model are not intended to provide exact verification of system performance for critical parameters such as fire flow as there are national field testing standards such as ISO and others that are better suited for this purpose. The water model was built using Epanet 2.0 and consists of 112 junctions, 123 pipes, 3 well reservoirs, 3 pumps and one storage reservoir (tank). Figure 12 below shows the water model map for the existing infrastructure. The round dots are junctions of two or more water lines and the lines between junctions represent pipes and are called links. Page 34 of 107

35 FIGURE 12 Domestic flow was modeled first using the average daily demand with a peaking factor for the peak month of July for an average net flow of 78 gpm. As expected the residual pressures are nearly identical to the static pressures for this small flow rate. The results are shown schematically in Figure 13. Junction colors indicate pressure in psi and link colors indicate system flow rates in fps. The legends show the values for each color. Page 35 of 107

36 Pressure psi Day 1, 12:00 AM Velocity fps FIGURE 13 Domestic Flow Results summary: System residual pressures in existing service area range from psi - well within acceptable limits. System residual pressures in Little River Ranch Stage 1 will range between psi. There are no indications of low-pressure problems in the system s service area. Fire flow was modeled at various locations in the current service area at various levels of flow to estimate the maximum available fire flow. Figure 14 below shows the results for the maximum fire flow the system would sustain on the north side of Highway 50 across the highway from Poncha Lumber. This site was chosen because the lumberyard most likely represents the highest fire flow demand in the current service area. Page 36 of 107

37 Pressure psi Velocity fps FIGURE 14 Highway Poncha Lumber Fire Flow Results Summary: The maximum obtainable fire flow while maintaining domestic flow is 900 gpm with a residual pressure of 38 psi which is above the minimum residual fire flow pressure of 20 psi. (ISO tests showed 960 gpm per hydrant) Pressures on western-most service area of highway 50 drop to 10 psi which is below the minimum required system pressure of 35 psi (note the red-colored junctions showing pressures below 20 psi). Domestic flow is maintained but at a degraded level throughout much of the system (yellow nodes denote pressures below the required 35 psi). Page 37 of 107

38 Pipe size, line distance from the storage tank and main looping are the primary limitations on the fire flow potential at this location. There is insufficient storage to maintain fire flows above 1500 gpm for required durations. For flow duration performance during fire flows see the storage analysis section. OPTIONS FOR DISTRIBUTION SYSTEM IMPROVEMENTS The distribution system splits into two distinct un-looped branches at the intersection of Highway 285 and the southern Highway 50 flyway. The system is not adequately looped to obtain maximum flow rates or to provide redundancy in the case of a main breakage. There are several options for improving the system fire flow performance. The option modeled to demonstrate performance improvement potential had the following changes: The two branches were looped with a 12 main on the northern service boundary along CR128. A storage tank was added north of town on highway 285 at the same elevation as existing tanks. The tank was connected to the system by a 12 main to the CR main. This option was modeled to demonstrate the potential performance improvement in fire flow. Figure 15 below shows the model with the physical improvements discussed above for the same flow site as the previous model. Results Summary, model with system improvements: Fire flow increased from 900 gpm to 3000 gpm - a 330% increase. Domestic residual pressures maintained above 20 psi in the system, specifically pressures on the western edge of the service area on Highway 50 where residual pressures maintained 23 psi even with the increased fire flow rate. At a 900-gpm fire flow rate residual pressures at the western edge of the service area improved from 10 psi to 50 psi. Page 38 of 107

39 Pressure Day 1, 12:00 AM psi Flow GPM FIGURE 15 An additional system improvement was modeled by additionally providing an 8 loop main from Pinyon Road to Poncha Springs Lane. The results are shown in Figure 16. In summary this additional improvement showed: An increase at the highway 50 site from 2500 gpm to 3000 gpm. An increase in fire flow capacity at the De Anza Vista Apartments & Poncha Springs Lane from psi residual pressure to psi residual pressure. Page 39 of 107

40 Pressure Day 1, 12:00 AM psi Velocity fps Figure 16 As mentioned, this system improvement is only one of many options. A tank in zone 3, 4 or 5 with a high-pressure trunk line would have similar impacts on the system performance. The key factors for fire flow are: Short distances from storage to the fire demand. Sufficient pipe sizes to sustain the flow without substantial reduction of residual pressures. Looped mains. High-pressure trunk lines where long distances are involved. Modeling results and design guidelines show: Minimum main sizes should be 8. Page 40 of 107

41 Trunk lines and mains in heavily commercial or industrial areas should be 12. Static pressures or domestic demand residual pressures should be 40-psi minimum. POTABLE WATER STORAGE STORAGE REQUIREMENTS Required storage capacity is driven by the following factors: The first factor is the amount of domestic storage that is required. o The State requires a minimum of one-day storage or 200 gallons per person, which would equate to 110,600 gallons at the current Town population. [1] o The peak monthly pumped daily average is currently 140,000 gpd and also should be considered. [1] The second factor is the amount of fire flow capacity required. o The State requirement is that the fire flow requirements established by ISO should be satisfied. ISO requirement for specific locations were provided in the previous section. [1] The third factor is the minimum amount of storage residual after a fire flow event. o Domestic service must be maintained during a fire event and after a fire event per State Standards [1]. o An arbitrary goal of ½ day peak month pumped daily average has been chosen = 70,000 gallons to provide a reasonable residual storage after a fire event. There is no specified standard for this parameter, and a half of day storage is considered a reasonable assumption. The fourth factor relates to keeping the stored water fresh and with a measurable trace of chlorine. o Treated supply water should be either pumped directly into the storage tanks to minimize tank retention time or the tank levels should be allowed to drop on a timed regular basis to ensure a regular flow of fresh water into the tank. If the second option is currently used, this level drop should be designed Page 41 of 107

42 into the tank storage volume. An arbitrary total tank volume variation has been chosen at ½ the peak month pumped daily average = 70,000 gallons. ANALYSIS OF EXISTING STORAGE CAPACITY The existing storage consists of two steel storage tanks located at an elevation of 7638 feet. The tank gross capacities and net water capacities are shown in Figure 17. GROSS NET gallons gallons TANK #1 160, ,000 TANK #2 100,000 92,500 TOTAL 260, ,500 FIGURE 17 The total available net storage capacity is 240,500 gallons at a full tank level of 18.5 feet. Figure 18 analyzes the existing storage for the various ranges of fire flow requirements. The maximum fire flow requirement that the existing storage can support is 1000 gpm for 2 hours while maintaining the minimum of 70,000 gallons of residual domestic storage; or 1500 gpm for two hours if a 45,000 gallon residual was considered to be acceptable. Clearly fire flow is the most demanding factor on potable water storage for a small water system. As the system grows, the fire flow requirement remains relatively constant and becomes a smaller percentage of the total storage. Page 42 of 107

43 EXISTING FIRE FLOW STORAGE CAPACITY 225, ,000 STORAGE (GALLONS) 175, , , ,000 75,000 50,000 25, gpm 234, , , , , , , gpm 234, , , , ,000 84,000 54, gpm 234, , ,000 99,000 54,000 9, gpm 234, , ,000 54,000 (6,000) 2500 gpm 234, ,000 84,000 9, gpm 225, ,000 54,000 (36,000) HOURS FIGURE 18 The Figure 19 below depicts schematically the primary elements in determining the minimum storage recommended based on the general requirements and assuming a 3000 gpm fire flow for 3 hours at the current Town population. Page 43 of 107

44 AIRSPACE VOLUME 70,000 GAL. 760,000 GAL. TOTAL TANK VARIATION 70,000 GAL. DOMESTIC RESIDUAL 80,000 GAL. ONE DAY STORAGE FIRE FLOW STORAGE 540,OOO GAL GAL FOR 3 HRS FIGURE 19 For fire flows in the range of gpm, the recommended minimum storage capacity is 760,000 gallons. This recommendation requires an expansion of 500,000 gross gallons in storage. GROWTH DEMANDS ON STORAGE CAPACITY Storage capacity must expand as growth places more demands on the water system. The storage capacity expansion requirement is based on the following rules and assumptions: If the growth occurs in a zone served by a storage site that currently meets fire flow storage requirements, and the growth does not increase the maximum fire flow demand, the fire flow storage requirement will not change. If growth occurs in a new zone that is not served by an existing storage site, a new storage site at sufficient elevation for that zone must meet both the domestic and fire flow requirements for that zone. Page 44 of 107

45 A storage tank can serve multiple zones if it is sized correctly and the distribution system from the tank to all service sites meets the fire flow requirements. Storage tanks are a major capital investment and decrease in cost per gallon as the tank size increases. WATER STORAGE CAPACITY IN ZONES 1 & 2 Figure 20 shows how growth rates of 5%, 10% and 15% effect storage requirements for zones 1 & 2 in five-year increments. The figure assumes a starting value of 750,000 gallons gross storage. Remember that storage tanks at the current tank elevations can serve Zone 1 & 2, so the growth rates shown on the chart relate only to these zones. The figure shows that with a gross 500,000 gallons added to the existing capacity for a total of 760,000 gallons; growth demand could be satisfied as far out as 2015 depending on the growth rate. GROSS STORAGE ZONE YEAR ,000,000 GALLONS 760,000 GALLONS ,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 FIGURE 20 GALLONS x 1,000 5% 10% 15% Figure 21 shows the system performance of 760,000 gallons of gross storage capacity during a fire event at 3000 gpm for 3 hours and the subsequent recovery time using a 150 gpm well pump rate. Page 45 of 107

46 (Thousands) gpm Fire Flow For 3 Hours Net Gallons Storage Hours FIGURE 21 At the end of the fire event there are 144,000 gallons of residual domestic storage. At a 150 gpm pump rate the tanks refill in 62 hours. WATER STORAGE CAPACITY IN ZONES 3-5 Growths in Zones 3 through 5 require a different analysis because not only domestic demand but also new fire storage demand must be provided. For example, the installation of a storage tank at an elevation of 8160 or greater feet, sufficient to serve Zone 5 with a high-pressure trunk line and zoning is shown in Figure 11. The example assumes that the maximum fire flow demand in Zones 3-5 is 1500 gpm for 2 hours resulting in a net fire storage demand of 180,000 gallons. The Friend Ranch Golf community proposes 569 residential units. At 2.3 persons per household the full build-out population will be approximately 1309 people resulting in a net domestic storage requirement of 262,000 gallons. The gross tank size required would be 500,000 gallons at full build out with maximum fire flow requirements of 1500 gpm and 750,000 gallons with a maximum fire flow requirement of 3000 gpm. Figure 22 shows predictions for 5%, 10%, 15% and 20% growth rates in Zones 3-5. The 20% growth rate was included to show the effect of a 25-year build out of the Friend Ranch community. The Page 46 of 107

47 figure shows that a 500,000-gallon tank would be a sufficient supply at a 15% growth rate until STORAGE REQUIREMENT ZONE YEAR GROSS GALLONS x 1,000 5% 10% 15% 20% FIGURE 22 RAW WATER SOURCES Poncha Springs currently obtains 100% of its raw water for potable water use from ground water source wells. EXISTING WATER RIGHTS According to a letter dated April 21, 2006 by Gary Thompson, W.W. Wheeler & Associates (Appendix C), the Town s current water rights can support approximately 490 water taps if the Town is willing to enforce water restrictions in severe drought years. The Town currently serves 245 active water taps as shown in Figure 23A, and there are approximately 142 vacant lots that should be considered as committed taps. Little River Ranch Stage II is requesting 70 taps, leaving approximately 33 taps available. It is assumed that the Friend Ranch project will provide water rights for its taps. Page 47 of 107

48 Water Rights Taps Tap Tap Available Availability Capacity (%) Town Capacity % Active Taps % Vacant Lots (committed taps) % Un-commited Taps % LRR-Stage II % Friend Ranch % Planning Capacity 1, % ** assumes Friend Ranch will bring water rights necessary for tap capacity FIGURE 23A Figure 23B shows projections for growth in active taps in 5% increments from 5% to 20%. The Figure illustrates that even at a 20% growth rate (49 homes/year) the actual capacity to serve active taps will not be reached until At 15% growth the tap capacity is reached at Figure 24 looks at water rights availability from the perspective of growth in vacant lots and committed taps. If lot growth continues at present rates, available water rights are consumed in the next few years and the future demand for additional water rights grow rapidly. The town will need to acquire additional rights soon and have a readily available source for water rights as the growth boundary area develops into additional lots. Page 48 of 107

49 WATER RIGHTS CAPACITY vs. HOUSE GROWTH RATES TAPS YEAR CAPACITY 5% 10% 15% 20% FIGURE 23B Tap capacity could be increased by the following actions without additional water purchases: The use of a package sewer plant to provide direct return flows to the South Arkansas River tributary. The amount of increase in tap capacity could be significant, would depend on several factors, and would require an in depth analysis by, or reviewed by, the Town s water engineer. The Town has a high unaccounted water use, and it may be possible to increase the tap capacity by reducing the amount of unaccounted water. For example, if unaccounted water could be reduced from 26% to 10% by leak repair, it would increase tap capacity by 16% or approximately 75 taps. However, if the accounted water issue is resolved by the new service meters, there would be no increase in tap capacity only an increase in service fee revenue. Page 49 of 107

50 WATER RIGHTS CAPACITY vs. LOT GROWTH RATES LOTS YEAR CAPACITY 5% 10% 15% 20% FIGURE 24 Water conservation can also increase tap capacity. For every 10% reduction in water use (gpcd or gphd) there is a corresponding 10% increase of 49 taps in capacity. Water conservation is one of the lowest-cost alternatives for increasing tap capacity. Because of the requirement to replace depletions to the South Arkansas River during the irrigation season s river calls, the tap capacity is limited by the peak summer month use during the crop irrigation season. It is recommended that a package wastewater plant be further studied and analyzed as a method of improving water rights availability for additional tap capacity. Page 50 of 107

51 FUTURE WATER RIGHTS The capacity to physically serve new developments does not have to be 100% in place at the time of lot creation. Build out of structures in rural areas typically range from years after lot creation and thus the storage, pumping and treatment capacity can be phased in as required with sufficient planning. Availability of water rights in the future cannot be assured, so it is prudent to have the water rights secured at the time of lot creation to assure a future build-able lot. Since Poncha Springs does not have a portfolio of water rights sufficient to service the growth area as defined in this study, policies need to be developed to ensure a sufficient water right capacity as the area develops, without hindering development or imposing an undue financial burden on the Town. The Town should have their water engineer and water attorney evaluate and provide recommendations for the best approach for the future availability and procurement of water rights to support the projected growth in the Growth Boundary Area. Some of the questions that should be considered are: Should the town purchase senior water rights on the tributary and dry up agricultural land? Should the town develop an agreement to purchase nontributary rights that can be imported into the tributary, such as the UAWCD is proposing with the Cameron Ditch water? Does use of non-tributary water improve the water efficiency equation by eliminating requirements for replacement of depletions during the irrigation season and does this create a significant cost benefit? Would a raw water storage lake west of town provide cost effective benefits to the overall water management equation if addition surface water rights are obtained. WATER SOURCE QUALITY Recent test results show water quality to be below Maximum Contaminant Levels (MCL) in all categories except Lead, Copper and Total Dissolved Solids (TDS). One potential risk factor that should be closely monitored is Total Combined Radium (Radium 226 & Radium 228). The EPA passed the Radionuclides Rule 66 FR December 7, The rule Page 51 of 107

52 limits Total Combined Radium to a 5 pci/l average for four consecutive quarters of test results. The cost of radium removal is very expensive and complicated. Radium removal costs can potentially double water rates. Four consecutive quarterly tests were performed on each of the Town s wells in Figure 25 summarizes the results and shows the maximum radium level allowed. Each source is allowed to average four quarters of data; the four-quarter average for each well is shown by a color-coded horizontal line. The bars are the quarterly results for each well. The data does not indicate any relationship to well pump rates or well depth. Well #3 tested higher levels than Wells #1 & #2. According to sources within the CDHPE, radium levels typically increase in the first and fourth quarters and decrease in the second and third quarters. Currently there is no scientific explanation for the seasonal variations. Local aquifers are recharged by surface water during spring and summer runoff. There is a time delay for these surface waters to reach the aquifer depending on the geology. If the time delay is short, the lower 2 nd & 3 rd quarter readings could be a result of dilution of the aquifer by surface infiltration. The long-term water infrastructure strategy should include mitigation of the risk for exceeding the combined radium strategy and (as a secondary goal) to not exceed the limit for any one quarter. There are several strategies for radium risk mitigation: Shut down any water source exceeding the limit. o This strategy works if other sources not exceeding the limit can handle the demand. A good strategy would be to use Well #2 in the 1 st and 4 th quarters and to minimize the use of Well #3 in these quarters. Blend low radium-level source water with high radium-level source water to produce a combined source below the regulatory limit. o Treated surface water could be blended with treated ground water to lower the combined radium level. The difficulty with this strategy is that well water is currently injected directly into the mains rather than a storage vessel where blending could occur. Page 52 of 107

53 Radium 226 & 228 Results pci/l WELL #1 AVERAGE COMBINED RADIUM MAX MCL WELL #3 AVERAGE 0 Feb-04 Mar-04 Apr-04 May- 04 Jun-04 Jul-04 Aug- 04 Sep-04 Oct-04 WELL 1 WELL 2 WELL 3 FIGURE 25A The recommended long-term strategy for combined radium risk mitigation is as follows: New treatment facilities should deliver water to storage rather than being injected directly into mains. Some surface water treatment could be considered for a portion of the total Town treatment capacity. If the surface treatment can operate year round, then it can act as a peaking capacity for summer demand and as a blending capacity for combined radium in the winter months. WATER SOURCE QUANTITY The Town currently has 3 wells and is in the process of drilling a 4 th well. Table 2 summarizes the average production versus demand load. Currently during peak summer months there is only a 34% pumping capacity margin. If Well #2 or #3 had an equipment failure during a peak summer month, the pump capacity would be insufficient to keep up with demand. Page 53 of 107

54 The new well will improve the pumping capacity margin to 55% if the expected pumping rate is achieved. Additionally, the new well will provide sufficient redundancy should there be a malfunction on Well #2 or #3. Yearly Monthly Annual Comments Average Peak Total (gpm) (gpm) (gal) Well # ,482,700 * only used in summer Well # ,974,200 Well # ,688,406 TOTALS ,145,306 CURRENT PEAK DEMAND Well #4 (to be drilled) ,688,406 ** projected production PROJECTED TOTALS *** with new well Table 2 According to a recent study by the U.S.G.S. entitled Hydrogeology and Quality of Ground Water in the Upper Arkansas River Basin from Buena Vista to Salida Colorado , the hydrology in the vicinity of the Town should support specific well yields of 10%-15%. Areas north of the highway and south of Town have the greatest potential for high specific yields according to Figure 4 of the U.S.G.S. report. This estimate corresponds to recent well yield experience with well #3. Changes in climate and land use around the Town could impact the hydrology in the future and should be monitored carefully. State water policies could also impact the availability of groundwater as a source. The following are recommendations for future well location determinations: Geology and Hydrology studies should be analyzed prior to any future well site selection to determine optimum locations for high specific yield. When possible wells should be drilled for high yield to minimize the number of treatment facilities. Each treatment facility must perform water quality tests that are Page 54 of 107

55 expensive and a recurring cost. Well yields in excess of 75 gpm should be set as a goal. Wells should be placed in safe zones away from commercial and industrial areas where groundwater pollution could threaten source water. Wells should be placed near storage tanks or storage tanks should be placed near wells, where feasible. Treated water should be pumped to storage and not directly into the distribution system. Storage is elevation-dependent while wells are hydrology dependant Wells should be sufficiently separated from other high production wells to minimize cross interaction of cones of depression. Industrial and agricultural wells should be discouraged in areas within 2500 feet of municipal wells. As the demand for raw water increases with the Town s growth, consideration should be given to treatment of surface water, if a year round source supply is available. The following are recommendations for future surface water policies: Land annexed into the Town should be required to retain the water rights associated with the land or to turn the water rights over to the Town so that the water rights maintain residency in the local area. Untreated surface water should be the preferred source of irrigation water. Pressurized, piped irrigation systems should be considered as a method of maintaining a green community at a low cost. WATER TREATMENT Poncha Springs currently uses two primary types of water treatment. Wells #1 & #2; use a gas chlorination process. Well #3 uses a hypo-chlorination process (liquid bleach). Gas chlorination is the least expensive treatment available for large treatment facilities. However, for small systems, the safety training and safety equipment required may offset general material and labor cost savings. Hypo-chlorination also has a reasonable material cost slightly higher than gas chlorination. However, this form of treatment has Page 55 of 107

56 minimal safety training and requires no special hazard safety equipment and has the lowest initial capital cost. A third form of treatment using tablet chlorination is becoming more prevalent in small systems. Tablet chlorination systems use pressed chlorine tablets. These systems have very low labor costs, but have a higher initial capital cost and higher recurring material costs. The benefit to a small system is the low maintenance and labor effort required to run the system with very consistent quality results. If the Town desires to transition from a contract operator to inhouse public works operators, it is recommended that the gas chlorination be eliminated and replaced with either liquid or tablet hypo-chlorination to reduce training and safety costs. The systems discussed above are primarily for ground water treatment. Should surface water treatment be considered, a package plant using ultra or micro membrane filtration technology should be considered. These systems are fully automated, require little custom design engineering and are modular so as demands increase package modules can be added to increase capacity. The package plants do not require large land areas. WASTEWATER INFRASTRUCTURE The Poncha Springs wastewater system is used for domestic wastewater only and is not a combined sewer system. Storm-water is not discharged into the sewer system. Existing Sewer System. Wastewater is channeled from laterals, sub-mains and mains to a central trunk line, which connects the Poncha Springs collection system to the Salida collection system and treatment plant. The sewer system consists of a system of gravity mains and manholes that channel all wastewater to a single 10 trunk line on the east of Town. This trunk line runs parallel with U.S. Highway 50 on the south side. A Poncha Springs sewer meter is just east of the town boundary and a Salida sewer meter is at the boundary as defined in the Salida Poncha Springs Wastewater Agreement. Currently the Town does not have any wastewater treatment facilities. The sewer trunk line runs from the Town s eastern boundary to the City of Salida. This trunk line is a 10-inch diameter pipe with an approximate average slope of ft/ft. Page 56 of 107

57 Sewer flows are metered by a Poncha Springs metering station located just east of Poncha Springs Lane on Highway 50, and a City of Salida metering station located at Xcel Energy pole #107 where the Harrington Ditch crosses U.S. Highway 50. The Poncha Springs metering station data is available from May 2001 to December The Salida metering station data is available from January 1, The purpose of this sewer planning analysis is to develop forecasting and planning information for the purposes of providing the following information: Determine the theoretical hydraulic capacity of the existing Poncha-Salida trunk line. Compare Ten States Standard (TSS) sewer forecast demand to actual 2005 & 2006 sewer metered data. Forecast remaining trunk line capacity based on the Poncha- Salida Sewer Agreement dated July 12, Compare the capacity prediction using TSS to the available metered data for actual flows. Determine the best approach for forecasting future sewer demand. Forecast sewer demand for: o Pending developments o Vacant lots within the existing Town boundary o Properties in the growth boundary o Proposed Friend Ranch THEORETICAL CAPACITY OF PONCHA-SALIDA TRUNK LINE The theoretical capacity of the trunk line was calculated using Manning s equation. The following inputs were used: Average Slope =0.017 ft/ft (from topographic contour map) Mannings roughness value n = (Civil Eng. Ref. Manual Appendix 19 A). Pipe size 10 inch inside diameter clay tile. Maximum capacity at depth of flow/ inside diameter (d/d) of 0.80 The calculated result is 680 gpm as a theoretical capacity of the trunk line with the conditions given above. The whole flow capacity Page 57 of 107

58 is not available exclusively to Poncha Springs. Customers are serviced east of the Salida metering station along the highway. This value would represent the flow capacity at the end of the 10 trunk line. Using the TSS (Ten States Standard) recommended value of 250 gpcd for a daily peak flow rate, the 680-gpm trunk line is estimated to have the capacity to serve a population of approximately 3900 people. SEWER DEMAND USING TEN STATES STANDARD (TSS) COMPARED TO METERED DATA This analysis compares wastewater demand forecasting using TSS compared to actual metered wastewater data for the calendar year General design criteria of the TSS for wastewater collection systems are as follows: Sanitary sewer sizing is commonly based on an assumed average of gpcd. 100 gpcd is a typical design value and includes normally expected infiltration. Many municipal codes restrict allowable infiltration to 500 gpd/mile inch of pipe. Modern pipe materials can limit infiltration to 200 gpd/mile-inch of pipe. Day-to-day flows can vary 100% from the Daily Average. Daily peaks can vary 225% from the Daily Average. Seasonal peaks can vary 100% from the Daily Average, and these peaks commonly occur. Peak flows of 400 gpcd are typically used for laterals and sub-mains flowing full. For mains and trunk lines a peak hourly flow of 250 gpcd is typically used. Using these design guidelines the following theoretical predictions were obtained and compared to the actual metered data from the Poncha metering station for 2005, and the results are presented in Table 3. Page 58 of 107

59 TSS TSS Metered Metered Daily Seasonal Daily Seasonal Average Peak Average Peak Flow Flow Flow Flow (gpd) (gpd) (gpd) (gpd) 55, ,600 35,006 85,033 * all data using population= 553 Table 3. Using TSS, with 250 gpcd as a daily peak load demand, the trunk line has the capacity to serve a population of approximately 3900 people (Poncha Springs taps + Salida taps on the trunk line). PONCHA SPRINGS SALIDA WASTEWATER AGREEMENT This analysis section attempts to analyze the current wastewater flow in the trunk line and the remaining capacity as defined in the Wastewater Agreement (Appendix D). The Agreement states that the flow to the discharge point may be up to but not more than an ultimate monthly average daily flow of 1130 EQR s or 271,200 gallons per day. From this wording it is assumed that the flow limit that cannot be exceeded in one month is 8,136,000 gallons. Poncha Springs has been metering sewer flow since 2001 and has used the sewer flow data to track a significant reduction in infiltration as was shown in Table 4. For the purposes of this analysis sewer data will be used from the calendar year 2005 so that the data used reflects the reductions made in infiltration. Figure 26A shows a comparison of sewer meter readings from the Poncha Springs meter and the Salida meter. There appears to be no correlation between the two sets of data. One or both of the meters is producing inaccurate data. It is recommended that the issue be mutually resolved with Salida as soon as possible. An explanation for the rapid slope increase in May could be infiltration in the trunk line section between the meters. A visual inspection of the flow levels in each meter location with a mechanical measurement of flow depth could verify if there is a real flow difference. Page 59 of 107

60 Sewer Meter Correlation 6,000,000 5,000,000 Gallons x 1,000 4,000,000 3,000,000 2,000,000 1,000,000 0 January February March April May June July August September October November December Meter Poncha Meter Salida FIGURE 26A The remaining capacity according to the agreement using average monthly gallons per day is shown in Figure 11. Monthly Avg. Population Households Peak Month Daily Flow Average Daily (gallons) (persons) (house equiv) Flow (gphd) $ M- Data July , WWA Maximum 271, Avail. Capacity 186, TABLE 4 The assumptions and values used for the data shown in Table 4 are as follows: The peak month [July 2005] metered flow from the Poncha Springs metering station was used to calculated monthly daily average flow. The current average per-capita and per-household demand will remain constant. Page 60 of 107

61 Infiltration will remain at current levels. In summary, metered data, gpcd & gphd show the approximate remaining sewer line capacity will serve an additional population of 1211, or 637 home equivalents because the agreement is structured on peak month daily average flow rather than annual daily average flow. FORECASTING WASTEWATER DEMAND There are two primary objectives to this section of the report. The first objective is to provide a forecast of the total potential wastewater demand in the study area at full build-out. Total potential wastewater demand in the study area is a function of these variables: Total acreage in the service area [Table 1 Parcel Analysis Section]. Development densities [Table 1 Parcel Analysis Section]. Per-household equivalent average daily demand rate in gphd [Figure 9 Historic Sewer Demand Section]. Peak Daily Demand for main and trunk sizing of 250 gpcd [TSS Standards] The full build-out sewer demand potential of the study area is summarized in Figure 26B. Table 1 contains parcel-specific data for average gpcd that can be used for rough estimates of demand impacts by parcel. It should be recognized that this data is valid only for general planning purposes and should not be used for design purposes. The second objective is to provide a forecast of a realistic wastewater demand growth rate. Two approaches were used to forecast growth. The first approach uses a simple linear growth rate as shown in Figure 26 for the study area. Page 61 of 107

62 % TAP GROWTH WWA CAPACITY NEW CAPACITY REQUIRED 20% % OF CAPACITY 15% HOUSE EQUIV. TAPS % 5% CURRENT DEMAND FIGURE 26B The second approach uses a 20-year build-out on existing lots and currently known proposed development (Friend Ranch, Little River Stage II, White Rock Canyon) as shown in Figure 27. By comparing the figures it can be seen that a 25 year build-out rate of these lots compares closely to a 20 25%% growth rate. Page 62 of 107

63 SEWER FORECAST FOR 25 YEAR BUILD-OUT RATE NEW CAPACITY REQUIRED WWA CAPACITY 80% OF CAPACITY TOTAL FRIEND RANCH TAPS SOLD VACANT LOTS LITTLE RIVER RANCH CURRENT DEMAND FIGURE 27 NEW WASTEWATER TECHNOLOGIES The purpose of examining new wastewater technologies in this study is to explore the possibilities of a wastewater plant for the Town with a discharge in the South Arkansas River. The Town has a limited wastewater agreement with Salida and the depletion aspect of sending wastewater flows to the main stem of the Arkansas limits the raw water resources of the Town during the summer months when 100% of the depletions to the South Arkansas River must be replaced. A wastewater plant could expand the growth capacity of both wastewater and potable water for the Town by reducing or eliminating depletion replacement bypass flows. Historically, wastewater plants have been complex plants as shown schematically in the Figure 28. The plants had a large footprint, were designed only for large capacities and were very labor intensive and capital intensive. Many of these historic plants are now struggling to meet new wastewater effluent standards and are requiring substantial retrofits. Page 63 of 107

64 New wastewater technologies are providing a technical solution using membrane bioreactor technology in pre-engineered package plants which will be referred to as MBR systems. FIGURE 28 These MBR plants can meet or exceed regulatory requirements for discharge or re-use effluent. Additionally, these systems have a very small footprint, are significantly automated and have short delivery times because of their pre-engineered/prefabricated approach. Figure 29 shows an example of an MBR plant being delivered in a pre-assembled building. Page 64 of 107

65 FIGURE 29 Figure 29AQ shows an example of another MBR plant that does not require a building structure. FIGURE 29A The effluent quality from MBR systems meets or exceeds standards in most cases for re-use or direct discharge. Figure 31 below shows a typical discharge quality in technical terms and Figure 32 shows a visual representation of the effluent quality. Page 65 of 107

66 Parameter BOD 5 TSS Ammonia Total Nitrogen Total Phosphorus Turbidity Fecal Coliform MBR Effluent Quality < 2 mg/l < 2 mg/l < 1 mg/l < 3 mg/l* < 0.05 mg/l* <0.2 NTU < 10 CFU/100 ml * With appropriate biological design and/or chemical addition. FIGURE 30 FIGURE 31 WASTEWATER SITE APPROVAL PROCESS The Colorado State Department of Public Health and the Environment (CDPHE) regulates the approval process for new Community Wastewater Treatment Plants. A meeting was held including all recognized organizations that could have a role or vested interest in the approval of a wastewater plant on the South Arkansas. The following bullets summarize the key results of the meeting: Attendees: Judy Lohnes (UACOG), Bruce Smith (State Engineers Office), Tim Vrudny, Gary Soldano & Kent Custer (CDPHE), Terry Scanga (UAWCD), Christine DeChristopher & Daniel Poole (Salida), Don Reimer (Chaffee County), Pat Alderton (Poncha Springs), Joe De Luca & Paul Crabtree (CGI) CDHPE prefers to minimize the number of wastewater plants. Page 66 of 107

67 CDHPE process requires approximately one year for approval and the first step is to apply for Preliminary Effluent Limits for the stream (PELs). This process costs approximately $ and is one of the first steps in the approval process. The City of Salida stated that the Wastewater agreement does not give Poncha Springs any rights to additional future capacity. The UAWCD strongly supports return flows to the tributaries for water rights and water availability. Once PEL s are available, a technology is picked that can meet the requirement, a financial analysis must show the best present value choice, one option must be the Salida Plant with any necessary expansion of the plant. The CDPHE stated that the treatment plant must be custom designed for the stream. (Package plants do come with options that provide various levels of effluent quality that can be tuned to meet the PELs.) Figure 32 is a schematic of the State Site Approval process from the Regulation 22 Guidance document for wastewater site approvals. Page 67 of 107

68 FIGURE 32 The first step in the approval process is the application for Preliminary Effluent Levels, the State website for obtaining the application is: WASTEWATER RETURN FLOWS TO MINIMIZE DEPLETIONS For a package plant to be effective in reducing depletion requirements, the plant must discharge very near the water supply well or diversion. Figure 33 is a simple schematic showing the dewatering aspect of current water and wastewater operations. Well withdrawals for all in-house use are transferred from the South Arkansas Tributary to the Main Stem of the Arkansas River by the wastewater trunk line, dewatering the tributary reach from Poncha to Salida. The depletion in this reach must be replenished to satisfy water rights owners with diversions along the subject reach. Both Salida and Poncha Springs contribute to the de-watering aspect. Existing development plans being discussed such as the Friend Ranch and Little River Ranch Stage II (LRR) as shown in Figure 34, will cause Poncha Springs to further dewater the tributary Page 68 of 107

69 reach, and in the case of the Friend Ranch will extend the dewatering in a westerly direction. The developments will also use up most of the available Waste Water Agreement capacity. South Arkansas DEWATERED SECTION Harrington Ditch Arkansas Salida 5500 Poncha Springs 550 Well Fields Limited Trunk Line Capacity & Limited By WWA, 271,200/day FIGURE 33 Arkansas Vandaveer 1000 Salida 5500 South Arkansas Tenassee DEWATERED SECTION LRR 350 Poncha Springs 550 Growth Boundary 5000 acres 6900 homes/pop 15,000 EXTENDED DEWATERING Well Fields Friend Ranch 600. FIGURE 34 Page 69 of 107

70 Salida will increase the dewatering of the tributary if they move the Tenassee water diversion upstream to the Harrington ditch diversion point. The City of Salida has plans to develop the Vandaveer Ranch with a potential of approximately 1000 equivalent single-family units. It is not clear that Salida will be willing to add capacity to the Poncha Springs Salida wastewater agreement, or if it will want to save available wastewater plant capacity for its own growth area. Figure 34 shows that with just the known pending developments there are an equivalent of 1950 single-family unit equivalents in some stage of planning. FRIEND RANCH PACKAGE TREATMENT PLANT Figure 35 shows a package plant for the Friend Ranch located on the eastern boundary of the ranch to minimize requirements for replacing depletions to downstream ditches. Harrington Murray LRR 350 Poncha Springs 550 Poncha Creek Well Fields Mcpherson- Burnett Scanga Lowland Ouray Cochetopa Creek Huntzicker Maxwell Springbrook Boone Hensie Friend Ranch 1300 Friend Ranch Well FIGURE 35 By installing a package plant at the Friend Ranch development, the existing excess Wastewater Agreement (WWA) capacity can be reserved for growth near and in the current Town boundaries in the water zones identified as #1 & #2. As shown in previous sections of this report, the existing capacity should support a 10-15% growth rate for 15 to 20 years. Page 70 of 107

71 WATER RATES STRUCTURE ANALYSIS There are two basic elements to water utility rates. The first is the Usage Rate and the second is the Connection Fee. The Usage Rate should cover operation, maintenance and replacement costs. The Connection Fee should cover system expansion costs to support system growth. An ideal Usage Rate structure for a utility would strive for a low basic monthly fee and would use an increasing block rate structure for any use above the minimum water requirement; that would cover the costs of the operational, maintenance and major replacement costs of the system. The Connection Fee needs to cover water rights replacement (including court and filing costs), replacement water storage (raw and potable), addition of distribution mains, pumping and treatment capacity. Also, some growth areas require a higher level of service than existing service areas, because of the type of treatment or other factors. TYPES OF USAGE RATE STRUCTURES There are three basic types of Usage Rate structures generally used by utilities. The four basic types are: Decreasing Block Rate: Water gets cheaper per gallon as you use more. So your first 3000 gallons used costs more than the next 5000 and the next 5000 costs even less. Uniform Rate: Water is the same price per gallon no matter how much you use. Increasing Block Rate: Water gets more expensive per gallon as you use more. Everyone pays a low cost for the first 3000 gallons, the next 5000 gallons cost 30% more per gallon and the next 5000 gallons costs 50% more than the previous 5000 gallons. This keeps the MWR (minimum water requirement) cost low and encourages conservation. Seasonal Rate: Has a higher rate in the summer than in the winter when demand is low. This is used to curb summer irrigation and can be combined with any of the previous rate structures. Colorado Springs combines seasonal with an increasing block rate structure. Page 71 of 107

72 The trend is toward Increasing Block rate structures to encourage water conservation and to keep the MWR cost low for low-income families. Recently some utilities have been experimenting with even more complicated rate structures to encourage conservation, especially in drought years. Some rate structures are based on each home s last year average use and sets a low rate structure for 70% of that value and then significantly increases block rates from this 70% value. Aurora is using this method; however this requires a sophisticated water billing system. Such a system is not currently practical for a small utility until the software cost is reduced. RATE STRUCTURE COMPARISONS This section provides some comparison data with local and similar sized utilities and with some of the major utilities in the state. One item of note is that the data in Figure 36 shows that if a utility has a high basic service fee, it can overwhelm the increasing block rate structure intent and the end result is a decreasing block rate structure. Aurora is the only city in the data that showed an increasing block rate structure, when the service fee was included. The figure shows that the Round Mountain Water District (Westcliffe & Silver Cliff), Buena Vista, Fort Collins and Poncha Springs have very similar rate structure costs with the exception of the initial MWR block because of variations in the service fee. Salida has one of the lowest water rates in the state. Pueblo and Glenwood Springs are close to the average for the state. The Poncha Springs rate structure is an increasing block rate structure before the service fee is included. As shown above in the figure when the service fee and block rate structure are combined, the result is a declining block rate. Of all of the cities and towns surveyed, it appears that Poncha Springs has the highest Usage Rate fees. It should be noted however that some of the rate structures reported were from 2004, while Poncha Springs rates are from 2006, so there may have been some increases. Currently the Town has a negative cash flow in their water fund, so any radical change in rate structure is not recommended. Page 72 of 107

73 3,000 5,000 10,000 15,000 20,000 $ $ $ $ $ $ 9.50 $ 9.00 $ 8.50 $ 8.00 $ 7.50 $ 7.00 $ 6.50 $ 6.00 Aurora $ 5.50 $ 5.00 $ 4.50 $ 4.00 $ 3.50 $ 3.00 Round Mtn. Fort Collins $ 2.50 Poncha Springs Buena Vista $ 2.00 Pueblo $ 1.50 Glennwood Springs $ 1.00 Salida $ 0.50 $ - 3,000 5,000 10,000 15,000 20,000 FIGURE 36 USAGE RATE STRUCTURE RECOMMENDATIONS Maintain the Town s existing service fee and block rate structure. Over time, strive to reduce the service fee and increase the while increasing the upper block rates. Set maximum limits for total annual usage based on tap size. WATER SYSTEM CONNECTION FEES The Water Connection Fee breakdown for a single-family unit ¾ tap is shown on Table 5. The table provides estimates on a single family household basis for the infrastructure and water rights costs of a tap. The current tap rate structure appears sufficient at this time to cover expected costs. However as discussed in the water analysis section, the purchase of water rights sufficient for a development requires a cash outlay at lot creation and the current Page 73 of 107

74 tap fee structure does not recover that cost until a tap is purchased which is typically just prior to the construction of a structure. WATER SYSTEM DEVELOPMENT FEES (per household) WATER RIGHTS $ 3, WELL & TREATMENT $ METERS, INSTRUMENTATION & BILLING EQUIP $ STORAGE $ DISTRIBUTION $ TOTAL TAP COST 3/4" $ 4, CURRENT TAP FEE (NEW LOTS) $5, TABLE 5 Therefore it is recommended that the current Water System Development Fee Structure be redefined into two separate fees. A Water Rights Development fee of $ would be purchased as a requirement for final plat for each buildable lot. o A developer could provide the necessary consumptive use water rights in lieu of the fee. (water rights converted and approved in water court for municipal use) An Water Infrastructure development fee of $ would continue to be purchased at construction time. Page 74 of 107

75 It is also recommended that maximum annual pumping limits be placed on each tap size for new tap purchases in gallons as shown in Table 6. Pipe size is not an indicator of water use and tap rates can be abused by a high-use water client. Service fees for high rates of water use only compensate the town for treatment costs, not the additional costs of more water rights. Water Water Maximum Average Development Infrastructure Annual Annual Fee Fee Gallons Gallons 3/4" Line $ 2, $ 2, ,000 55,000 1" Line $ 3, $ 3, , " Line $ 8, $ 8, ,000 TABLE 6 Page 75 of 107

76 CONSERVATION VALUES AND POLICIES Conservation programs have been instituted across the country with positive results. The table 7 below provides a summary of recent conservation policies and practices that the Town could consider in their ongoing water conservation efforts. Table 7 Page 76 of 107