AUGUST 30, 2016 DRAFT WATER SYSTEM PLAN TEXT AND TABLES BYWATER BAY WATER SYSTEM WITHOUT SHINE PLAT

Transcription

1 AUGUST 30, 2016 DRAFT WATER SYSTEM PLAN TEXT AND TABLES BYWATER BAY WATER SYSTEM WITHOUT SHINE PLAT

2 1. SYSTEM OVERVIEW The Bywater Bay Water System (DOH Water System ID number 02043P) is located in eastern Jefferson County just west of the Hood Canal Bridge. The original water system was constructed in 1992 by Pope Resources. The Bywater Bay well had limited capacity. Therefore, Pope Resources proposed an intertie to the Shine well owned by Jefferson County PUD. The PUD granted the request and Pope Resources constructed the transmission main and developed the Shine Well. All title and interest in the water system was transferred from Pope Resources to the PUD November 15, In 1998 the PUD formed LUD#11, which extended the water system to include the Shine Road area. Later in 2000, the PUD extended the system to include the Sound View Villa Water System. The Bywater Bay Water System currently has 215 active connections and is approved for a total of 272 (DOH Sentry Internet Data 2016). The estimated population served by the Bywater Bay Water System is 400 (estimated using 1.9 people per connection). 2. SERVICE AREA The existing service area and system boundary is shown on Figure 1. This Figure also shows a projected future service area and system boundary as shown in the Jefferson County GIS System (August 2016) 3. EXISTING FACILITIES The Bywater Bay Water System components are shown in Figure 2. As shown in the system's schematic drawing (Figure3), the system includes three pressure zones. The mid zone is gravity fed from the Bywater reservoir. The high pressure zone is served through two 3 HP booster pumps capable of meeting maximum instantaneous demand and one 25 HP pump available for fire flow. The lower zone is feed from both the mid-level pressure zone through a Pressure Reducing Station (PRS), and from a separate 130,000 gallon water reservoir. Insert Figure 1 Service Area Insert Figure 2 - Water System Components Insert Figure 3 System Schematic An inventory of Bywater Bay infrastructure is presented in Table 1.

3 Table 1 System Infrastructure Bywater Bay System Component Description Quantity Units Distribution System 1" Water Main Polyvinyl Chloride Pipe 90 LF 2" Water Main Polyvinyl Chloride Pipe 3516 LF 4" Water Main Polyvinyl Chloride Pipe 7406 LF 6" Water Main Polyvinyl Chloride Pipe LF 8" Water Main Polyvinyl Chloride Pipe LF Reservoirs Shine Reservoir Bywater Reservoir Pumps Concrete, 130,000 gallon reservoir, 35 feet high 26 feet diameter, overflow EA Concrete, 85,000 gallon reservoir, 75 feet high, 14 feet diameter, overflow EA Booster Pump Twin Goulds 3 HP Alternate Start Up 1 EA Fire Booster Pump Berkley 25 HP Fire Booster 1 EA Wells Well #1 (Bywater) Well #2 (Shine) PRS Shine Pressure Zone Treatment ATEC System (Bywater) ATEC System (Shine) 8 inch diameter, 295 feet deep, screened in two locations in lower aquifers, 150 gpm 1 EA 8 inch diameter, 255 feet deep, 30 gpm 1 EA 2 inch and 6 inch PRVs in parallel 1 EA 150 gpm Iron and Manganese Removal Unit 1 EA 30 gpm Iron and Manganese Removal Unit 1 EA Wells # 1 (Bywater) and #2 (Shine) serve as the sources of supply to the Bywater Bay Water System. Well #1 is drilled to a depth of 295 feet with a pumping capacity of 150 gallons per minute. Well #2 is drilled to a depth of 255 feet with a pumping capacity of 30 gallons per minute. The well pumps are activated by radio telemetry connected to on-off floats located in the

4 reservoir. Water is pumped into the distribution system from the sources to the Bywater (midzone) reservoir. The Bywater (mid-zone) reservoir is a concrete structure 14 feet inside diameter and seventy-five feet high (overflow at 410') with a storage capacity of 85,000 gallons. The Shine reservoir is a concrete structure 26 feet in-side diameter and overflow at feet. Bottom drain is at 249 feet with the inlet/outlet at feet with a total of 130,000 gallons. The Shine reservoir is fed through a PRS located on old Stark Road just south of SR 104. Because of the high levels of Iron and Manganese in the ground water the PUD purchased and installed two ATEC Iron and Manganese removal units at the well sites. The systems work through the adsorption process. Chlorine is injected into the well water just prior to the treatment unit; this starts the oxidation process and allows the iron and manganese to be adsorbed by the filter medium. The filter vessels are back-washed periodically into infiltration ponds near the pump houses. The system maintains a free chlorine residual as a result of the treatment system - not because of any DOH requirement to chlorinate the system. 4. CONNECTIONS, WATER USE, AND GROWTH Water use has been developed using data from 2009 to Water pumped vs. metered along with calculated unaccounted water (UW) is shown in Table 2. The reported number of connections has not changed in the last 7 years. Average Day Demand (ADD) per connection was 195 gallons per day (gpd) averaged over the last 5 years. Table 2 Historic Water Use Bywater Bay YR Average No. of Connections Average Annual Water Use* (Million gallons per year) Average Day Water Use (gpd, Includes UW)* UW % UW 18.0% 11.7% 7.6% 3.5% 2.8% 5.7% 4.8% 1.6% 3.7% ADD (gpd) *Data from Water Use Efficiency Reports PUD and DOH

5 Under most scenarios, population served is an estimate. The recent population planning numbers for Jefferson County (based on census data) range from 1.4 to 2.0 persons per household. However connections are a more reliable measure of system responsibility when compared with water consumption data. For this document, focus is on water consumption per residential connection (ERU), and approved County growth rates (2015 Growth Management Steering Committee). For the study areas of unincorporated Jefferson County, the accepted growth rate projection is 0.62% per year. This is considerably lower than planning projections used in the last County Comprehensive Plan (1998 and as amended in 2005) and the last Water System Plan (2011). Growth projections using the adopted growth rate (0.62%) and using the number of connections (215) over the past few years as a starting point, are shown in Table 3. Of note is the fact that the Bywater Bay Water Service area is primarily zoned one unit per five acres. There is considerable undeveloped land in this area which could foster development which would dramatically increase the demand for water service. Even under the Growth Management Act, there are mechanisms to allow this to happen, but there are also controls to promote orderly planning and development. One example of potential demand is contained in the 1995 Transfer Agreement between Pope Resources and the PUD is attached (Attachment 1). Pope Resources is allocated 125 connections under the Agreement. As of the date of the agreement Pope Resources had connected 49 of these, leaving a PUD commitment of 76 future connections. The status of meeting this commitment is currently unknown. Other systems in the vicinity of the Bywater Bay System include the Shine Plat Water System, and the Paradise Bay Water System (Jefferson County Water District # 1). Both entities would like to connect to Bywater Bay. These systems are shown as a future service areas on Figure 1. Table 3 Growth Projections Bywater Bay Year Connections* Estimated Population** * Connections based on 0.62% per year growth **Population estimate based on 2 people per connection Monthly data is not available at this time because of computer system changes and staff workload at the PUD. This data would be used to develop Maximum Month Average Day Demand (MMADD). This number is used to calculate Maximum Day Demand (MDD) which is in turn used to determine adequate storage. Instead MMADD was obtained from the 2011 water

6 system plan. The 2011 result was a MMADD of 559 gpd. Maximum day demand (MDD) was calculated using a factor of 1.7 times the MMADD. The result is 950 gpd. Since recent data is not available currently, calculations for storage in this document will use the 2011 MDD of 950 gpd for storage calculations, and the ADD shown in Table SOURCE ANALYSIS / WATER RIGHTS Below is a summary of the Bywater Bay Water System water rights: Well Number 1 (Bywater) Permit or Certificate #: G Name of Right holder: Jefferson County Public Utility District No. 1 Priority Date: July 13, 1990 Source Number: Well No. 1 Maximum Instantaneous Flow Rate Allowed: 150 gallons per minute (gpm) Annual Withdrawal Quantity Allowed: 136 acre-feet per year Type: Primary Well Number 2 (Shine) Permit or Certificate #: G Name of Right holder: Jefferson County Public Utility District No. 1 Priority Date: July 13, 1990 Source Number: Well No. 2 Maximum Instantaneous Flow Rate Allowed: 30 gpm Annual Withdrawal Quantity Allowed: 27 acre-feet per year Type: Primary Proposed Well Number 3 (Reynolds Well) Permit or Certificate #. Pending DOE processing Name of Right holder: Jefferson County Public Utility District No. 1 Priority Date: 10/02/1992 Source Number: Well No. 3 Maximum Instantaneous Flow Rate Allowed: Pending (30 gpm assumed minimum) Annual Withdrawal Quantity Allowed: No Increase Type: Supplemental Current pumping capacity is equivalent to the water rights and is shown in Table 4 in gallons per day (GPD).

7 Table 4 Current Pumping Capacity (Water Rights) Bywater Bay Source Available Well # 1 (150 gpm), GPD 216,000 Well #2 (30 gpm), GPD 43,200 Total Source, GPD 259,200 Using the data from Table 2, average customer use over the last 5 years and average system efficiency were used to project water demand over the next 20 years. These numbers are shown on Table 5. Table 5 Demand and Source Analysis No. of Connections Average Annual Water Use* (Million gallons per year) Total Production (Million gallons per year, includes UW)* Total Production (Annual Acre Feet) Water Right (Annual Acre Feet) Suplus / (Deficit) Acre Feet (water right) Peak Day Water Use (gpd at 950 gpd per connection)** 204, , , , ,126 Water Right (gpd) 259, , , , ,200 Pumping Capacity (gpd) 259, , , , ,200 Surplus / (Deficit) (gpd) 54,950 48,539 41,927 35,108 28,074 *Based on average annual use / demand by customers over the last 5 years ** Based on PDD of 950 gpd calculated from the MDD for the Peak Month A comparison of annual withdrawal quantity allowed (163 acre feet per year or 53 million gallons) to average annual water use indicates that the system will operate well within its annual withdrawal limits throughout the twenty year planning period. The pumping capacity / instantaneous water rights also will be sufficient over the planning horizon.

8 6. STORAGE ANALYSIS Water for firefighting is part of system design, and storage is critical because of the relatively immediate water demands with relatively high flows. Planning level fire flow requirements for the Bywater Bay Water System are established by the 1997 Coordinated Water System Plan (CWSP) and are shown in Table 6. Table 6 Jefferson County Fire Flow Water System Design Requirements Land Use Designation Rural Areas (>1 acre parcel size) Residential Commercial Industrial Fire Flow Design Requirement None 500 gpm for 30 minutes 1000 gpm for 60 minutes 1500 gpm for 60 minutes The Bywater Bay Water Service area is a rural area and primarily zoned one unit per five acres. As shown in Table 6, fire flow is not required for the Bywater Bay Water System in accordance with the CWSP. However, the system was designed by the developer and later by the PUD to provide fire flow at 500 gpm for 30 minutes. This information is combined to form the basic storage assumptions which are presented in Table 7.

9 Table 7 Basic Storage Assumptions Bywater Bay Required Fire Flow (gpm) 500 Fire Flow Duration (minutes) 30 Average Daily Demand (gpd) 195 Maximum Month ADD (gpd) 559 Maximum Daily Demand (gpd) 950 Source Available Well # 1 (150 gpm), gpd 216,000 Well #2 (30 gpm), gpd 43,200 Well #3 (30 gpm), gpd 43,200 Total Source, gpd 302,400 Storage Available Reservoir #1 Bywater, gal 85,000 Reservoir #2 Shine, gal 130,000 Total Available Storage, gal 215,000 Operational Storage Operational Storage is calculated based on the on and off pump settings. An analysis of each of the Bywater Bay reservoirs provides the following: Shine Water Reservoir OF: Outlet: Base: 249 Dia: 26 feet Operational Storage: 1 feet Gal/ft: 3,971 Operational Storage 3,971 gallons Total Storage: 127,083 gallons Bywater Water Reservoir OF: 410 Dia: 14 feet Operational Storage: 2 feet Base: Gal/ft: 1,151

10 Operational Storage 2,302 gallons Total Storage: 84,632 gallons Total required operational storage is 6,273 gallons. Fire Storage Although not required by Jefferson County, the ability to use the system for firefighting was part of the original design. The level of fire flow for residential is 500 gpm for 30 minutes or 15,000 gallons (CWSP). The PUD has been allowed by the County Fire Marshal to nest the fire flow requirement with standby storage. This means the larger of the two requirements is used in the storage calculations. Equalizing Storage Equalizing storage is a function of Peak Hourly Demand (PHD). Equation 9-1 of the 2009 Department of Health Water System Design Manual (Design Manual) was used. PHD for this system was calculated based on ERUs and MDD. The required MDD value was obtained from the 2011 Water System Plan. The details of PHD calculation can be found within Table 5-1 and Equation 5-1 of the Design Manual. The resulting equalizing storage values with predicted ERU growth are shown in Table 8. Standby Storage This system is a multi-source system. Therefore, Equation 9-3 of the Design Manual was used to calculate this storage requirement. This equation gives credit for the supply provided by an additional source. This calculation is also a function of the number of connections (ERUs) and ADD (Table 2). These results are also shown in Table 8 along with the other storage requirements. Storage Summary Storage requirements for equalizing and standby storage change over time change as ERUs increase. As discussed above, the Design Manual was used to develop Table 8 specific to the ERUs projected in the future. This Table shows that there is a surplus of storage over the planning period.

11 Table 8 Storage Analysis Bywater Bay Storage Available Reservoir # 1 (Bywater) 85,000 85,000 85,000 85,000 85,000 Reservoir #2 (Shine) 130, , , , ,000 Total Available Storage 215, , , , ,000 Storage Required ERUs Operational Storage (gal)** 6,273 6,273 6,273 6,273 6,273 Equalizing Storage (gal) 25,674 27,010 28,387 29,808 31,273 Standby Storage (gal) 40,650 43,282 45,996 48,796 51,683 Fire Storage (gal) * 15,000 15,000 15,000 15,000 15,000 Total Storage Required* (gal) 72,597 76,564 80,656 84,877 89,229 Storage Surplus/(Deficit) 142, , , , ,771 *Nested Standby and Fire Storage (largest value was used) ADD 195 gpm (Table 2) **OS was based on 2 foot for Bywater and 1 foot for Shine (2,302 & 3,971 gal respectively) 7. ERU LIMITING CALCULATIONS Using the procedure in Section 6.7 of the Design Manual, limitations of the source and storage components of the system were evaluated. Source: ERU capacity determinations based on water supply were completed using Equations 6-3 and 6-4 of the Design Manual. These two equations compute ERU capacity in two different ways: The first relies on annual supply of water and ADD, and the second uses daily pumping capacity and MDD. For the annual supply, the total water right was used instead of an annual pumping capacity since the water right provides a more conservative calculation (provides less supply than continual pumping of the sources). A water right of 163 acre feet was used. The results are provided in Table 9. This Table indicates that the more restrictive use of MDD and pumping capacity limit the connections (ERUs) to 273. Table 9 Results of ERU Limit Calculations Method ERU Capacity # ERUs Source (Equation 6 3, DOH) 746 # ERUs Source (Equation 6 4, DOH) 273

12 Storage: The equalizing storage requirement is shown in Table 8, and developed according to the Design Manual. This Table 8 shows the planning requirement and the numbers are reflective of the increasing numbers of connections (ERUs). However, following the procedure in Section 6.7 of the Design Manual, this required equalizing storage was compared against potentially available equalizing storage as described in the iterative process below. To undertake this process, calculation of PHD was completed based on various ERU scenarios. ERU values of 200 to 500 where chosen. PHD was calculated using coefficients from Table 5-1 and Equation 5-1 of the Design Manual. The MDD was obtained from the 2011 Water System Plan and maximum monthly data. The PHD results are presented in Table 10 for scenarios involving increments of connections ranging from 200 to 500. Table 10 Peak Hourly Demand Bywater Bay Number of Connections* PHD *Projected connections at 2035 are estimated at 243 (Table 3) Equalizing storage requirements were then calculated using the Design Manual factors for the ERU scenarios and procedure in Section 6.7 of the manual. This results in an ERU limit between 400 and 500 EURs (Table 11). Then using Equation 6-6 of the design manual, the ERU limit was calculated at 416. Table 11 Storage Requirement Scenarios Bywater Bay Storage Required 250 ERU 300 ERUs 400 ERUs 500 ERUs Operational Storage ,273 6,273 6,273 Equalizing Storage (gal) ,507 59,320 77,132 Standby Storage (gal)* , , ,800 Fire Storage (gal)* ,000 15,000 15,000 Total Storage Required (gal) ,205 Non Equalizing Storage ,073 total storage 215, , , ,000 ES Available 139, ,927 80,927 41,927 *nested Standby and Fire Storage largest was used and ADD of 195 gpd was used

13 ERU capacity based on standby storage was estimated by meeting all storage requirements, then dividing the remaining storage available by the DOH recommended minimum standby storage of 200 gallons per ERU. This resulted in a standby storage based ERU limit of 747 ERUs when the equalizing was limited in the ERU level. The current ERU limit for the system is set at 272 connections and is based on source capacity (DOH Sentry Internet Data 2016) and is consistent with the source limited number developed above. 8. WATER QUALITY All testing is done in accordance with the DOH Annual Water Quality Monitoring Schedule. The Schedule is attached (Attachment 2). DOH maintains records of all water quality testing on their website (DOH Sentry Internet Data 2016) and therefore will not be repeated here. Coliform monitoring for the Bywater Bay Water System has occurred monthly with no failed samples since the PUD has taken over the system (1995). Samples tested for various inorganic chemical and physical parameters indicated that Well #1 routinely exceeds the Maximum Contaminant Levels (MCLs) for manganese and that Well #2 routinely exceeds MCLs for turbidity, iron and manganese. After the use of the ATEC adsorption treatment, the water meets MCLs for all inorganic chemicals. Testing results for lead and copper levels have been satisfactory. The PUD tests for regulated and unregulated Volatile Organic Compounds (VOC). Although there was a positive result in June of 1996 from initial testing of Well #3, VOC s have not been detected in subsequent testing. There is no record of any violations of radionuclides levels Synthetic Organic Compounds (SOC) have been analyzed for the Bywater Bay Water System with no detected levels of concern. The Bywater Bay Water System is not required to test for asbestos because there are no asbestos cement pipes within the system. Chloride is an indicator of salt water intrusion. One of the provisions of the water rights for Wells #1 and #2 states that in conjunction with DOH bacteriological sampling, the water quality is required to be tested for chloride concentration once every three months. If the chloride concentration exceeds 50 mg/i, the withdrawal rate of the well will be reduced.