EXISTING SYSTEM ANALYSIS

Chapter 6 EXISTING SYSTEM ANALYSIS This chapter describes the evaluation of the existing water distribution system, using the calibrated hydraulic model and the 2006 water demands. The system evaluations are based on the criteria described in Chapter 4. This section covers the following evaluations: System pressures. Pipeline velocity and headloss. Storage capacity. Pump station capacity. Water supply. Age replacements. The system evaluations are discussed first, while the proposed improvements that are required to address the identified deficiencies are summarized at the end of this Chapter. The evaluation of the water system under future demand conditions is discussed in Chapter 7. 6.1 SYSTEM PRESSURES The City s calibrated hydraulic model was used to evaluate the system pressures for the following criteria: Meet Peak Hour Demands (PHD) while maintaining a minimum pressure of 40 psi. Meet Minimum Day Demands (MinDD) while not exceeding a maximum pressure of 80 psi. Meet Maximum Day Demands (MDD) with fire flow while maintaining a minimum pressure of 20 psi. 6.1.1 Pressures with PHD The evaluation of system pressures under PHD conditions is conducted by performing a steady-state run with the calibrated model, using a 2.7 multiplier (see Table 2.8) for the average day demands (ADD). The evaluation of results is limited to the junctions along pipelines that have service connections. These nodes are also referred to as demand nodes. Model junctions that are located at water system facilities, such as the water treatment plant (WTP), are excluded from the pressure evaluation, as the minimum pressure criterion does not apply at these locations. It is assumed that both the PS at the WTP and the La Brucherie PS are operational during PHD conditions. FINAL - February 13, 2008 6-1 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

Based on the model results, it can be concluded that all 2,976 demand nodes maintained a pressure above 40 psi under PHD conditions. Figure 6.1 shows the pressure distribution among the demand nodes. The pressures ranged from 52 to 62 psi. 6.1.2 Pressures with MinDD The evaluation of system pressures under MinDD conditions is conducted by performing a steady-state run with the calibrated model, using a 0.7 multiplier (see Table 2.8) for the ADD. Similarly to the system evaluation under PHD conditions, the evaluation of model results is also limited to the demand nodes. It is assumed that the PS at the WTP is operational, while La Brucherie PS is assumed to the off-line during MinDD conditions. Based on the model results, it can be concluded that all 2,976 demand nodes maintained a pressure below 80 psi under MinDD conditions. Figure 6.2 shows the pressure distribution among the demand nodes. The pressures ranged from 56 to 64 psi. 6.1.3 Pressures with MDD Plus Fire Flow The evaluation of system pressures under MDD plus fire flow conditions is conducted by performing a steady-state run with the calibrated model, using a 1.6 multiplier (see Table 2.8) for the ADD and adding the appropriate fire flow demand to each model node based on the fire flow requirement associated with the land use designation of the surrounding parcels (see Table 4.1). The only nodes evaluated for the MDD plus fire flow are junctions that are in close proximity to a fire hydrant. For example, nodes at the end of a dead-end main (in a cul-de-sac) without a fire hydrant were excluded from the analysis, as these locations would not experience the high water demand associated with a fire. It is assumed that there will only be one fire at a time. In addition, it is assumed that both the PS at the WTP and the La Brucherie PS are operational during a fire. The fire flow analysis consists of two steps: Standard Fire Flow Analysis. Detailed Fire Flow Analysis. During the Standard Fire Flow Analysis, the model conducts one model run for each junction that is associated with a fire hydrant. For each run, the system-wide MDD was used plus the respective fire flow demand was added to one of the model nodes. The simulation was repeated until all fire hydrant nodes were evaluated. The El Centro model contains 2,883 hydrant nodes, thus 2,883 separate model runs were conducted during this analysis. FINAL - February 13, 2008 6-2 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

Treshill Rd Austin Rd La Brucherie Rd A³ Clark Rd Fourth St Dogwood Rd Cooley Rd AÌ Legend Sphere of Influence City Limits Cruickshank Rd Facilities Villa Rd La Brucherie 1 Reservoir (5 MG) and Pump Station (400 hp) [ WTP Reservoir Pump Station Pressure at Junctions Evan Hewes Hwy < 40 psi 40-44 psi 45-49 psi Orange Ave 50-54 psi >= 55 psi Pipelines by Diameter Ross Rd 8" and Smaller!"_$!"_$ 10" and Larger Danenberg Rd Water Treatment Plant (15 mgd) 3 Reservoirs (10 MG) Pump Station (800 hp) [ Feet 0 3,000 6,000 McCabe Rd A³ AÌ FIGURE 6.1 PRESSURES UNDER PHD CONDITIONS WATER MASTER PLAN CITY OF EL CENTRO

Treshill Rd Austin Rd La Brucherie Rd A³ Clark Rd Fourth St Dogwood Rd Cooley Rd AÌ Legend Sphere of Influence City Limits Cruickshank Rd Facilities Villa Rd La Brucherie 1 Reservoir (5 MG) and Pump Station (400 hp) [ WTP Reservoir Pump Station Pressure at Junctions Evan Hewes Hwy < 56 psi 56-57 psi 58-59 psi Orange Ave 60-61 psi >= 62 psi Pipelines by Diameter Ross Rd 8" and Smaller!"_$!"_$ 10" and Larger Danenberg Rd Water Treatment Plant (15 mgd) 3 Reservoirs (10 MG) Pump Station (800 hp) [ Feet 0 3,000 6,000 McCabe Rd A³ AÌ FIGURE 6.2 PRESSURES UNDER MINDD CONDITIONS WATER MASTER PLAN CITY OF EL CENTRO

At the end of this analysis, 209 nodes were identified as deficient as the residual pressure (MDD with the fire flow demand) resulted in pressure below 20 psi. These 209 nodes were then further evaluated using the Detailed Fire Flow Analysis. During the detailed analysis, the deficiencies were re-evaluated using the following procedures: Verification that the model node represents a true hydrant location using GIS and aerial photography. Verification that the model node has the correct fire flow criterion assigned. In locations where two or more land use categories border, the most conservative fire flow requirement was assigned to the model nodes. However, in some cases, such as parallel pipelines or parcel division, the lower fire flow requirement could be more appropriate. Modifications were made where necessary. Redistribution of the fire flow demand over two or three model nodes, versus one node, at locations where the requirement exceeds 2,000 gpm. As fire hydrants are typically not capable of providing more than 1,500 to 2,000 gpm, it is more realistic to divide a 3,000 gpm fire flow demand over two nodes that represent hydrant locations. The analysis is repeated with the redistributed fire flow demand to verify if the residual pressure is still less than 20 psi. After a detailed evaluation of the 209 nodes, 50 nodes remained deficient and require improvements to increase the residual pressure to more than 20 psi. Figure 6.3 shows the nodes with a pressure of at least 20 psi under the Standard Fire Flow Analysis (nodes in green), nodes with a pressure of at least 20 psi after the Detailed Fire Flow Analysis (nodes in yellow), and nodes that were not able to meet the 20 psi criterion and require improvements (nodes in red). The proposed improvements that address the remaining deficiencies (red nodes in Figure 6.3) are summarized in Table 6.1. As shown, a total of 17 projects with a combined length of approximately 19,260 linear feet (3.6 miles) are proposed. 6.2 VELOCITY AND HEADLOSS The City s hydraulic model was used to evaluate the existing pipeline velocities and headloss for the following criteria: Pipeline velocities shall not exceed 5 ft/s during MDD conditions. Pipeline headloss shall not exceed 10 ft/1,000 ft during MDD conditions. FINAL - February 13, 2008 6-5 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

FINAL - February 13, 2008 6-6 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc Table 6.1 Project ID Fire Flow Improvements Water System Master Plan City of El Centro Length (ft) Diameter (in) Street From To Comments FF-1 1,700 8 Alley Between East Holt Ave and East Heil Ave South First St South Hope Ave Replace existing 6 and 4-inch FF-2 (a) 1,600 12 Villa Rd North Third St 770 feet East, then 750 feet South FF-2 (b) 1,500 8 San Diego Ave North Third St 770 feet East, then 600 feet North Close loop Parallel existing 6-inch FF-3 900 8 South Fourth St Wensley Ave Ross Ave Replace existing 4-inch FF-4 700 8 East Main St Mc Cullom St South Dogwood Rd Close loop FF-5 800 8 Maple Ave South Third St Railroad Parallel existing 6-inch FF-6 700 8 Hamilton Ave South Third St Railroad Parallel existing 6-inch FF-7 600 8 Heil Ave South Third St Railroad Parallel existing 6-inch FF-8 1,800 8 South Second St Heil Ct Ross Ave Replace existing 6-inch FF-9 700 8 Cedar Ave South Third St Railroad Parallel existing 6-inch FF-10 (a) 1,500 12 1,250 ft North of Commercial Ave. FF-10 (b) 500 8 1,250 ft North of Commercial Ave. FF-11 900 12 North Fourth St and Villa Rd 200 feet South of Villa on North 4th St North Third St North First St Replace existing 8-inch North First St 460 feet East Replace existing 6-inch North to Villa Rd and East to Oak St Close loop FF-12 (a) 700 8 North Fourth St Euclid Ave Adams Ave Replace existing 6-inch

FINAL - February 13, 2008 6-7 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc Table 6.1 Project ID Fire Flow Improvements Water System Master Plan City of El Centro Length (ft) Diameter (in) Street From To Comments FF-12 (b) 600 8 Adams Ave North Fourth St East 600 feet to the dead-end FF-12 (c) 600 8 El Centro Ave North Fourth St East 600 feet to the dead-end Replace existing 6-inch Replace existing 6-inch FF-13 800 8 South Fourth St Olive Ave Orange Ave Replace existing 4-inch FF-14 600 8 South-West of Ross Ave and South Eighth St. Parallel existing 6-inch FF-15 1,400 12 Main St Imperial Ave North Twelfth St Close Loop FF-16 300 8 Applestill Rd 400 feet East of Sperber Rd 250 feet West of Betty Jo Mcneece Loop FF-17 (a) 300 12 South Second St Wake Rd South and East to Private Property FF-17 (b) 1,000 8 Wake Rd 1000 feet East of Corfman Rd (State Hwy 86) South Second St Total 20,200 n/a n/a n/a n/a n/a Parallel existing 8-inch Close loop Parallel existing 8-inch

Treshill Rd Austin Rd La Brucherie Rd A³ Clark Rd Fourth St Dogwood Rd Cooley Rd AÌ Legend Sphere of Influence City Limits Cruickshank Rd Villa Rd La Brucherie 1 Reservoir (5 MG) and Pump Station (400 hp) FF-11 FF-2 Facilities [ WTP Reservoir Pump Station Evan Hewes Hwy Orange Ave FF-15 FF-5 FF-12 FF-6 FF-13 FF-7 FF-10 FF-4 FF-1 Junctions 20 or more psi 20+ psi after further analysis Deficient Nodes Pipelines Fire Flow Improvement FF-3 FF-8 Existing Pipelines Ross Rd FF-14 FF-9!"_$ FF-17!"_$ Danenberg Rd Water Treatment Plant (15 mgd) 3 Reservoirs (10 MG) Pump Station (800 hp) [ Feet 0 3,000 6,000 McCabe Rd FF-16 A³ AÌ FIGURE 6.3 PRESSURES UNDER MDD PLUS FIRE FLOW CONDITIONS WATER MASTER PLAN CITY OF EL CENTRO

It is assumed that both the PS at the WTP and the La Brucherie PS are operational during MDD conditions. Based on the model results, it can be concluded that all pipes meet the velocity and headloss criteria. Therefore, no recommendations are made. 6.3 STORAGE CAPACITY EVALUATION The storage capacity evaluation consists of a comparison of the existing storage and the required storage per the criteria described in Chapter 4. This comparison is summarized in Table 6.2. Table 6.2 Existing Demands Storage Capacity Evaluation Water System Master Plan City of El Centro Description Quantity Unit Average Day Demand (ADD) 8.6 mgd Maximum Day Demand (MDD) 13.8 mgd Required Storage Operational Storage (30 % of MDD) 4.1 MG Fire Flow Storage (4,000 gpm for 4 hours) 1.0 MG Emergency Storage (100% of MDD) 13.8 MG Total Required 18.9 MG Available Storage 15.0 MG Surplus/(deficit) -3.9 MG As shown in Table 6.2, the City currently has 15 million gallons (MG) of treated water storage, while the required storage is 18.9 MG. Thus, the City has a storage deficit of 3.9 MG. The following four potential locations are identified to construct additional treated water storage: Location A - the WTP site: A new treated water reservoir could be constructed at this site, which would avoid the need for land acquisition. Location B - the La Brucherie site: A second tank could be constructed at this site, which would avoid the need for land acquisition. Location C - the site of the abandoned elevated storage tank near the intersection of South 8th Street and Vine Street. The use of this site would require demolition of the existing facilities and the space is limited to two 2.5-MG storage tanks. FINAL - February 13, 2008 6-9 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

Location D - a new site near the Lerno or Waterford development in the northwestern or southeastern part of the City, respectively. A site on the eastern part of the City would provide a more even distribution of treated water storage. However, a new site would require land acquisition and a new pump station. These potential locations are shown on Figure 6.4. It is recommended that a 5-MG treated water reservoir be constructed at the WTP. Storage should be constructed at the WTP site prior to adding storage in the distribution system to provide a buffer for the treated flow during low-demand conditions. 6.4 PUMP STATION CAPACITY EVALUATION The pump station (PS) capacity evaluation consist of a comparison of the existing pumping capacity and the required pumping capacity per the following evaluation criteria: Normal Conditions: Meet PHD with the largest pump unit out of service. Power Outage (system-wide): Meet MDD with back-up power only. Earthquake: Meet ADD with the largest PS out of service. As described in Chapter 2, the existing MDD is 1.6 times ADD (8.6 mgd or 6,000 gpm) or approximately 9,600 gpm and the existing PHD is 2.7 times ADD or approximately 16,100 gpm. As described in Chapter 4, the City has one PS at the WTP site and one PS at the La Brucherie site. The WTP PS has four (4) 4,000 gpm pump units, while the La Brucherie PS has two (2) 4,000 gpm pump units. The City has full back-up power at both the WTP PS site and at the La Brucherie PS site. Because the PS building at the WTP is old and in poor condition, it is assumed that this PS would not be operational during an earthquake. However, the PS has survived many earthquakes in the past, including the 1979 earthquake with a magnitude of 6.5 on the Richter scale. The pump station capacity evaluation is summarized in Table 6.3. Table 6.3 Evaluation Condition Pump Station Capacity Evaluation Water System Master Plan City of El Centro Available Capacity Meet PHD with largest unit 20,000 (1) out of service (1) Required Capacity Difference Unit 16,100 1,400 gpm Power Outage (2) 20,000 (2) 9,600 9,200 gpm FINAL - February 13, 2008 6-10 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

Table 6.3 Evaluation Condition Pump Station Capacity Evaluation Water System Master Plan City of El Centro Available Capacity Required Capacity Difference Unit Earthquake (3) 8,000 (3) 6,000 2,000 gpm Notes: (1) One unit is assumed to be out of service at the WTP PS. The remaining capacity consist of 3 * 4,000 gpm at the WTP PS and 2* 4,000 gpm at the La Brucherie PS. (2) During a system-wide power outage, both pump stations are operational with back-up power, however one unit is assumed to be out of service at the WTP PS. (3) It is assumed that the entire PS at the WTP PS is destroyed, while all units at the La Brucherie PS are assumed to remain operational. As shown in Table 6.3, the City has sufficient pump station capacity and back-up power at both the WTP PS and the La Brucherie PS to meet the evaluation criteria. Therefore, no recommendations are made. 6.5 WATER SUPPLY EVALUATION The existing system water supply evaluation consist of the analysis of: 1. Outage of the largest supply source. 2. Power outage. 3. Earthquake. 4. Transmission main breaks. The assumptions and findings of these analyses are described in the following subsections and are summarized in Table 6.4. 6.5.1 Largest Source Out of Service The evaluation criterion states that the City should be able to meet MDD for seven (7) days with the largest source out of service. The largest and only source of supply is the City s WTP, thus storage is the only available source of water when the WTP is out of service. The City s MDD is 13.8 mgd, which equals 96.3 MG over seven (7) days. The total available storage is 15.0 MG when all tanks are completely full. However, it is assumed that the reservoirs at the WTP site (10 MG) and the La Brucherie site (5 MG) are only about 70 percent full at the time of any emergency, resulting in 10.5 MG of supply. Based on the comparison of the required and available supplies, it can be concluded that the City has a supply deficit of nearly 86 MG when the WTP is out of service for seven days. FINAL - February 13, 2008 6-11 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

FINAL - February 13, 2008 6-12 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc Table 6.4 Water Supply Evaluation Water System Master Plan City of El Centro Supply Condition Required Supply (MG) Supply from WTP Site (MG) Supply from La Brucherie site (MG) Total Available Supply (MG) Surplus/Deficit (MG) Largest Source (WTP) Out of Service 96.3 7.0 3.5 10.5-85.8 (1) Power Outage at the WTP 3.5 5.8 2.9 8.6 5.2 Power Outage at La Brucherie PS 3.5 5.8 0.0 8.6 5.2 Earthquake - Destroying the WTP Site Facilities Earthquake - Destroying the La Brucherie Site Facilities 84.3 0.0 3.5 3.5-80.8 (1) 84.3 217.0 0.0 217.0 132.7 Notes: (1) This deficit can be met by the temporary distribution of raw water from one of the IID canals. Boil-water notifications would need to be sent to the City s customers and the Department of Health Services. The City has access to multiple IID canals within a few miles of the WTP site. Temporary above ground pipelines could be installed if the canal adjacent to the WTP would not be available.

As the City has only one source of supply and the construction of sufficient storage to meet this criterion is cost prohibitive, the City could distribute raw water into its distribution system during a prolonged outage of the entire WTP. It should be noted that the WTP an outage of the entire WTP is unlike because the plant has 100 percent back-up power from diesel generators. However, if a complete WTP outage occurs, the City could use the supplies from the raw water ponds and bypass the plant to continue water service and fire flow protection. As stated previously, boil-water-notices would need to be issued to inform the City s customers and the Department of Health Services. Initially, the City could use the 10.5 MG of treated water storage, which would be depleted after approximately 18 hours under MDD conditions and 29 hours under ADD conditions. During this time, the City would need to install some temporary above ground piping and pump installations to connect the raw water supply with the suction side of the WTP PS. Once this connection is established, the City could use the 52.5 MG of raw water from its storage ponds. This would provide an additional 3 days and 20 hours of supply, totaling about 4.5 days of water supply under MDD conditions. The raw water ponds can directly be supplemented from the canal through the raw water PS to continue a raw water supply for as long as needed. The hydraulic model was used to verify the system pressures under this scenario. The model results show that the system pressures range from 52 to 62 psi, as long as enough supply is available. It is estimated that the supplies would be depleted after approximately 18 and 30 hours under MDD and ADD conditions, respectively. 6.5.2 Power Outage The evaluation criterion states that the City should be able to meet MDD for 6 hours during a power outage. Two cases were evaluated: 1. A power outage shutting down the WTP PS. 2. A power outage shutting down the La Brucherie PS. The City s existing MDD is 9,600 gpm, which equals 3.5 MG over 6 hours. As discussed in Section 6.4, the City has 100 percent backup power capacity at the WTP PS and La Brucherie PS sites to keep all pump units operational at all times. It is assumed that the available storage from the reservoirs is limited to 70 percent of the full capacity, resulting in 7 MG at the WTP site and 3.5 MG at the La Brucherie site. 6.5.2.1 Outage at the WTP Site The available pumping capacity with a power outage at the WTP site is 16,000 gpm, which equals 5.8 MG over six hours. This pumping capacity governs the available supply because FINAL - February 13, 2008 6-13 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

it is less than the 7 MG available supply from the storage tanks. The available pumping capacity at the La Brucherie PS is 8,000 gpm or 2.9 MG in six hours. This is also less than the 3.5 MG available from storage at this site, so the pumping capacity governs at both locations. The total available supply during a power outage at the WTP and La Brucherie sites is 8.6 MG, which is 5.1 MG more than the required supply of 3.5 MG. Thus, the evaluation criterion is met. The hydraulic model was used to verify the system pressures under this scenario. The model results show that the system pressures range from 51 to 60 psi. 6.5.2.2 Outage at the La Brucherie Site As the City has full back-up power at both locations, the available pumping and storage capacities are the same during a power outage at the WTP and the La Brucherie PS. As described above, the total available supply would be 8.6 MG, which is 3.5 MG more than the required supply. Thus, the evaluation criterion is met and the system pressures are predicted to range from 51 to 60 psi. 6.5.3 Earthquake The evaluation criterion states that the City should be able to meet MinDD for 14 days in case of an earthquake. Two cases were evaluated: 1. An earthquake destroying the WTP site facilities. 2. An earthquake destroying the La Brucherie PS site facilities. The City s existing MinDD is 6.0 mgd, which equals 84.3 MG over 14 days. As discussed previously, it is assumed that the available storage from the reservoirs is limited to 70 percent of the full capacity, resulting in 7 MG at the WTP site and 3.5 MG at the La Brucherie site. 6.5.3.1 Earthquake Destroying the WTP Site The only available supply after an earthquake that damages the facilities at the WTP site is the storage at the La Brucherie tank. The available supply in storage is 3.5 MG, which is less than the available pumping capacity (8,000 gpm or 11.5 mgd). Thus, the storage volume governs. As shown in Table 6.4, the total supply deficit accumulated over 14 days is 81 MG. As stated in Section 6.5.1, the City s water system is vulnerable to extreme emergencies such as earthquakes due to its single source of supply and additional remote storage is cost prohibitive to address this deficiency. The use of raw water with boil-water-notices would also apply to the earthquake scenario. If the raw water inlet structure would be destroyed, the City could construct temporary above ground pipelines to other IID canals to continue its water supply service. FINAL - February 13, 2008 6-14 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

To minimize the impact of an earthquake of the City s water supply, it is recommended that a detailed emergency response plan for the WTP be kept up to date. In addition, the City could decide to purchase spare parts of key components with long delivery times to facilitate fast repairs. The hydraulic model was used to verify the system pressures under this scenario. The model results show that the system pressures range from 52 to 66 psi, as long as enough supply is available. It is estimated that the supplies would be depleted after approximately 12 hours. 6.5.3.2 Earthquake Destroying the La Brucherie Site When earthquake damages the facilities at the La Brucherie site, the system can be supplied from the WTP and WTP PS. As shown in Table 6.4, the available supply from the WTP site would be 217 MG, which is based on a WTP production of 15 mgd during 14 days and 7 MG of storage. This is more than the required supply of 84 MG, thus, the criterion is met. The hydraulic model was used to verify the system pressures under this scenario. The model results show that the system pressures range from 52 to 65 psi. These are normal operating pressures as the La Brucherie PS would be off during MinDD conditions to allow the tank to refill. 6.6 TRANSMISSION MAIN BREAKS The evaluation criterion states that the City should be able to maintaining a minimum pressure of 40 psi during a major transmission main break. The hydraulic model was used to verify the system pressures with the ten major pipeline breaks. The location of these hypothetical pipe breaks are shown on Figure 6.4, while the model results and proposed recommendations are summarized in Table 6.5. As listed in Table 6.5, the system pressures range from 49 to 59 psi under most pipe break conditions. However, three of the ten pipe breaks that were modeled resulted in a substantial pressure drop with areas where the system pressures were below 40 psi. The locations of these pipe breaks and the recommended pipe break (PB) improvements are listed in Table 6.5. FINAL - February 13, 2008 6-15 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

Treshill Rd Austin Rd La Brucherie Rd A³ Clark Rd Fourth St Dogwood Rd Cooley Rd AÌ Legend Sphere of Influence City Limits Cruickshank Rd Facilities Potential New )A Reservoir Locations Villa Rd La Brucherie 1 Reservoir (5 MG) and Pump Station (400 hp) [ WTP Reservoir Pump Station Evan Hewes Hwy B) D Break-5 D D Pipe Break Sites (No Deficiencies) Pipe Break Sites (With Deficiencies) Orange Ave Ross Rd D C) Break-6 D Break-7 Exisitng Pipelines (<= 12-inch) Existing Pipelines (>= 14-inch) Recommended Pipe Break (PB) Improvements!"_$ Danenberg Rd PB-3 (18-inch, 1200 ft) PB-2 (12-inch, 1600 ft) Break-10 Water Treatment Plant (15 mgd) 3 Reservoirs (10 MG) Pump Station (800 hp) Break-2 Break-1 D [ A) D D D D D Break-8 Break-3 Break-4 D Break-9 PB-1B (20-inch, 5300 ft) D)!"_$ Alternative PB Improvement Feet 0 3,000 6,000 McCabe Rd A³ PB-1A (12-inch, 2800 ft) AÌ FIGURE 6.4 POTENTIAL STORAGE SITES AND PIPE BREAK ANALYSIS WATER MASTER PLAN CITY OF EL CENTRO

Table 6.5 Pipe Break Pipeline Breaks Water System Master Plan City of El Centro Location 1 30-inch diameter pipeline on South 8th Street from Jacaranda Drive to Danenberg Avenue. 2 30-inch diameter pipeline on South 8th Street from Driftwood Drive to 350 feet north of Wake Avenue. 3 24-inch diameter pipeline on South 8th Street from Aurora Drive to Driftwood Drive. 4 20-inch diameter pipeline on Horne Road from South 8th Street to State Highway 86. 5 18-inch diameter pipeline on La Brucherie Road from the La Brucherie Tank to West Main Street. 6 18-inch diameter pipeline on Hamilton Avenue from South 8th Street to 340 feet east of South 8th Street. 7 12-inch diameter pipeline on Ross Avenue from South 2nd Street to 230 feet west South 2nd Street. 8 18-inch diameter pipeline on 8th Street from Horne Road to Manuel Ortiz Avenue Min. Pressure (psi) Max. Pressure (psi) Recommendation 43 56 None 37 58 PB-3: Install a 1,200 lineal ft 18-inch parallel pipeline on Wake Avenue from Cypress Drive to the 18-inch on Imperial Avenue. (New pressure is 42 to 58 psi) 49 59 None 49 59 None, assuming there is a connection to the 20-inch diameter pipeline at Danenberg Avenue and Fourth St. 49 59 None 49 59 None 52 62 None 0 62 PB-2: Create loop by installing a 1,600 lineal ft 12-inch diameter pipeline on Imperial Avenue from Danenberg Drive to Manuel Ortiz Avenue. (New pressure is 52 to 62 psi) FINAL - February 13, 2008 6-17 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

Table 6.5 Pipe Break Pipeline Breaks Water System Master Plan City of El Centro Location 9 20-inch diameter pipeline on Danenberg Road from Dogwood Road to 275 feet east of Dogwood Road 10 18-inch diameter pipeline on Nuffer Road, from Imperial Ave. to 1,320 feet eastward. Notes: Min. Pressure (psi) Max. Pressure (psi) Recommendation 0 62 PB-1 A: Create loop by installing a 2,800 lineal ft 12-inch diameter pipeline on Valley Vie Avenue from Fransworth Road to Dogwood Road. (New pressure is 52 to 62 psi) PB-1 B: Alternative proposed 5,300 lineal ft 20-inch diameter pipeline from Ross Rd. to Danenberg Rd, approximately 2,600 ft east of Dogwood Rd. (1) 52 63 None (1) If alternative PB-1 B will be installed prior to 2015, then this option should be chosen. However, if the installation of this pipeline is dependent on growth in the area and will not be installed in the near future, then PB-1 A should be chosen to mediate the affects of Pipe Break 9. FINAL - February 13, 2008 6-18 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

6.7 AGE REPLACEMENTS As shown in Table 3.3, the City does not have any pipelines that are more than 75 years old. However, it should be noted that 27 miles of pipelines in the GIS have an unknown year of installation. If any of these pipelines were installed before 1940, those should be replaced by year 2015. Fifty percent of the pipes with an unknown year of installation are included in the CIP to provide sufficient budget for replacements. A summary of the pipes selected for replacement is shown in Table 6.6. Table 6.6 Note: Pipe Age Replacement Water System Master Plan City of El Centro Improvement ID Diameter (inches) Length (1) (miles) Age-1 4 0.6 Age-2 6 7.4 Age-3 8 6.0 Total n/a 14.0 1) These recommendations are based on 50 percent of the pipelines with unidentified year of installation. The actual location and prioritization of these replacements should be determined with a separate study and field coupon testing to access the condition of individual pipelines. 6.8 SUMMARY OF RECOMMENDATIONS The existing system analysis identified the following improvements: FF-1 thru FF-17: 17 fire flow improvement projects with a combined length of nearly 4 miles. T1: 5 MG of reservoir storage. PB-1 thru PB-3: 3 pipe break improvement projects with a combined length of approximately 1 mile. Age-1 thru Age-3: 14 miles of pipeline replacements due to age. FINAL - February 13, 2008 6-19 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch06.doc

Chapter 7 FUTURE SYSTEM ANALYSIS This chapter describes the evaluation of the future water distribution system, using the calibrated hydraulic model modified for the anticipated future developments and the demands projected for year 2015 and build-out conditions. The system evaluations are based on the criteria described in Chapter 4. This section covers the following evaluations: System pressures. Pipeline velocity and headloss. Storage capacity. Pump station capacity. Water supply. Each analysis is discussed along with the recommended improvements that are required to address the identified future system deficiencies. These proposed improvements are also summarized at the end of this chapter. These existing and future system improvements are combined in the capital improvement program (CIP), which is discussed in Chapter 8. To conduct these system analyses, the hydraulic model was modified to include future demands (existing plus growth demand) and a backbone pipeline network to serve the 2015 developments and the entire sphere of influence (SOI) for build-out conditions. The future system model demand scenarios are summarized in Table 7.1, while the future distribution system network is shown on Figure 7.1. Table 7.1 Future System Demands Water System Master Plan City of El Centro Demand Scenario Peaking Factor * ADD Demand (mgd) Demand (gpm) Year 2015 MinDD 0.7 6.5 4,500 ADD 1.0 9.3 6,400 MDD 1.6 14.8 10,300 PHD 2.7 25.0 17,400 Build-Out MinDD 0.7 19.5 13,600 ADD 1.0 27.9 19,400 MDD 1.6 44.7 31,000 PHD 2.7 75.4 52,400 FINAL - February 13, 2008 7-1 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

Treshill Rd Cruickshank Rd Villa Rd Austin Rd La Brucherie 1 Reservoir (5 MG) and Pump Station (400 hp) La Brucherie Rd A³ Clark Rd Fourth St Future Northwest Reservoir and PS Site Dogwood Rd Cooley Rd AÌ Future Northeast Reservoir and PS Site Legend Sphere of Influence City Limits Existing Facilities [ WTP Reservoir Pump Station Recommended Facilities Evan Hewes Hwy Reservoir* Pump Station* Existing Pipes Orange Ave Future Pipes * Potential Locations (subject to change) Ross Rd!"_$!"_$ Danenberg Rd [ Future Southeast Reservoir and PS Site Feet 0 3,000 6,000 Water Treatment Plant (15 mgd) 3 Reservoirs (10 MG) Pump Station (800 hp) McCabe Rd A³ AÌ FIGURE 7.1 FUTURE DISTRIBUTION SYSTEM NETWORK WATER MASTER PLAN CITY OF EL CENTRO

7.1 SYSTEM PRESSURES The City of El Centro s (City) calibrated hydraulic model was used to evaluate the system pressures for the following criteria: Meet peak hour demands (PHD) while maintaining a minimum pressure of 40 psi. Meet minimum day demands (MinDD) while not exceeding a maximum pressure of 80 psi. Meet maximum day demands (MDD) with fire flow while maintaining a minimum pressure of 20 psi. 7.1.1 Pressures with PHD The evaluation of system pressures under PHD conditions is conducted by performing a steady state run with the calibrated model, using a 2.7 multiplier (see Table 2.8) for the average day demands (ADD). The evaluation of results is limited to the junctions along pipelines that have service connections. These nodes are also referred to as demand nodes. Model junctions that are located at water system facilities, such as the water treatment plant (WTP), are excluded from the pressure evaluation, as the minimum pressure criterion does not apply at these locations. It is assumed that both the pump station (PS) at the WTP and the La Brucherie PS are operational during PHD conditions. 7.1.1.1 2015 Based on the model results, it can be concluded that all 2,984 demand nodes maintained a pressure above 40 psi under PHD conditions. Without any additional booster station or storage facilities, the system pressures under PHD conditions ranged from 51 to 60 psi. 7.1.1.2 Build-Out Based on the model results, it can be concluded that only 500 demand nodes maintained a pressure above 40 psi under PHD conditions, while 2,600 demand nodes showed pressures below 40 psi. Additional booster station capacity at the WTP, the La Brucherie PS, and new facilities in the northwestern (NW), northeastern (NE), and southeastern (SE) parts of the City are required to increase the system pressure in the entire SOI above 40 psi. The system pressures under PHD conditions with the new facilities ranged from 46 to 63 psi. The sizing and potential locations of these additional PS facilities is discussed in Section 7.4, while the pressures under PHD conditions without and with these new PSs are shown on Figure 7.2 and Figure 7.3, respectively. As shown on these figures, the additional storage and pump stations are required to meet the pressure criteria throughout the SOI. FINAL - February 13, 2008 7-3 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

Treshill Rd Austin Rd La Brucherie Rd A³ Clark Rd Fourth St Dogwood Rd Cooley Rd AÌ Legend Sphere of Influence City Limits Cruickshank Rd Villa Rd La Brucherie 1 Reservoir (5 MG) and Pump Station (400 hp) Existing Facilities [ WTP Reservoir Pump Station Pressure at Junctions < 40 psi Evan Hewes Hwy 40-44 psi 45-49 psi 50-54 psi Orange Ave >= 55 psi Existing Pipes Future Pipes Ross Rd!"_$!"_$ Danenberg Rd [ Feet 0 3,000 6,000 McCabe Rd Water Treatment Plant (15 mgd) 3 Reservoirs (10 MG) Pump Station (800 hp) A³ AÌ FIGURE 7.2 SYSTEM PRESSURES UNDER BUILD OUT PHD CONDITIONS WITHOUT NEW PS FACILITIES WATER MASTER PLAN CITY OF EL CENTRO

Treshill Rd Austin Rd La Brucherie Rd A³ Clark Rd Fourth St Dogwood Rd Cooley Rd AÌ Legend Sphere of Influence City Limits Cruickshank Rd Villa Rd La Brucherie 1 Reservoir (5 MG) and Pump Station (400 hp) Future Northwest Reservoir and PS Site Future Northeast Reservoir and PS Site Existing Facilities [ WTP Reservoir Pump Station Pressure at Junctions < 40 psi 40-44 psi Evan Hewes Hwy 45-49 psi 50-54 psi >= 55 psi Orange Ave Ross Rd Recommended Facilities Reservoir* Pump Station* Existing Pipes Future Pipes!"_$ Danenberg Rd Water Treatment Plant (15 mgd) 3 Reservoirs (10 MG) Pump Station (800 hp) [!"_$ Future Southeast Reservoir and PS Site * Potential Locations (subject to change) Feet 0 3,000 6,000 McCabe Rd A³ AÌ FIGURE 7.3 SYSTEM PRESSURES UNDER BUILD OUT PHD CONDITIONS WITH NEW PS FACILITIES WATER MASTER PLAN CITY OF EL CENTRO

7.1.2 Pressures with MinDD The evaluation of system pressures under MinDD conditions is conducted by performing a steady state run with the calibrated model, using a 0.7 multiplier (see Table 2.8) for the ADD. Similar to the system evaluation under PHD conditions, the evaluation of model results is also limited to the demand nodes. It is assumed that the PS at the WTP is operational, while La Brucherie PS and the three new PS facilities are assumed to be offline during MinDD conditions. Based on the model results, it can be concluded that all demand nodes will maintain a pressure below 80 psi under MinDD conditions at year 2015 and build-out. Figure 7.4 shows the pressure distribution among the demand nodes at build-out. The majority of the pressures are predicted to range from 55 to 73 psi. 7.1.3 Pressures with MDD Plus Fire Flow The evaluation of system pressures under MDD plus fire flow conditions is conducted by performing a steady state run with the calibrated model using a 1.6 multiplier (see Table 2.8) for the ADD and adding the appropriate fire flow demand to each model node based on the fire flow requirement associated with the land use designation of the surrounding parcels (see Table 4.1 and Figure 4.1). The only nodes evaluated for the MDD plus fire flow are junctions that are in close proximity to a fire hydrant. For example, nodes at the end of a dead-end main (in a cul-de-sac) without a fire hydrant were excluded from the analysis, as these locations would not experience the high water demand associated with a fire. It is assumed that there will only be one fire at a time. In addition, it is assumed that all booster pumping stations at the WTP, the La Brucherie site, and the new pump stations in the NE, SE, and NW part of the City are operational during a fire. Similar to the existing system fire flow analysis, the fire flow analysis consists of two steps: 1. Standard Fire Flow Analysis. 2. Detailed Fire Flow Analysis. The modeling procedures of each step are discussed in detail in Section 6.1.3. The fire flow analysis model results show that there are no deficient fire flow nodes during both 2015 and build-out conditions. Hence, no recommendations are made. FINAL - February 13, 2008 7-6 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

Treshill Rd Austin Rd La Brucherie Rd A³ Clark Rd Fourth St Dogwood Rd Cooley Rd AÌ Legend Sphere of Influence City Limits Cruickshank Rd Villa Rd La Brucherie 1 Reservoir (5 MG) and Pump Station (400 hp) Future Northwest Reservoir and PS Site Future Northeast Reservoir and PS Site Existing Facilities [ WTP Reservoir Pump Station Pressure at Junctions < 40 psi 40-44 psi Evan Hewes Hwy 45-49 psi 50-54 psi >= 55 psi Orange Ave Recommended Facilities Ross Rd Reservoir* Pump Station* Existing Pipes Future Pipes!"_$!"_$ * Potential Locations (subject to change) Danenberg Rd McCabe Rd Water Treatment Plant (15 mgd) 3 Reservoirs (10 MG) Pump Station (800 hp) [ A³ AÌ Future Southeast Reservoir and PS Site Feet 0 3,000 6,000 FIGURE 7.4 SYSTEM PRESSURES UNDER BUILD OUT MINDD CONDITIONS WITH NEW PS FACILITIES WATER MASTER PLAN CITY OF EL CENTRO

7.2 VELOCITY AND HEADLOSS The City s hydraulic model was used to evaluate the pipeline velocities and headloss for the following criteria for the 2015 and build-out scenarios: Pipeline velocities shall not exceed 5 ft/s during MDD conditions. Pipeline headloss shall not exceed 5 ft/kft during MDD conditions. It is assumed that all booster pumping stations at the WTP, the La Brucherie site, and the new pump stations in the SE, NE, and NW part of the City are operational during MDD conditions. Based on the model results, it can be concluded that all pipes meet the velocity and headloss criteria under 2015 and build-out conditions. 7.3 STORAGE CAPACITY EVALUATION The storage capacity evaluation consists of a comparison of the existing storage and the required storage per the criteria described in Chapter 4. This comparison for both 2015 and build-out conditions is summarized in Table 7.2. Table 7.2 Storage Evaluation Water System Master Plan City of El Centro 2015 Build-Out Unit ADD 9.3 27.9 mgd MDD 14.8 44.7 mgd Required Storage Operational Storage 4.4 13.4 MG Fire Flow Storage 1.0 1.0 MG Emergency Storage 14.8 44.7 MG Total Required Storage 20.2 59.1 MG Current Available Storage 15.0 15.0 MG Surplus/Deficit -5.2-44.1 MG As shown in Table 7.2, the City currently has 15 million gallons (MG) of treated water storage, while 20.2 MG of storage is required in year 2015. Hence, 5.2 MG of additional storage needs to be constructed by year 2015. FINAL - February 13, 2008 7-8 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

The required storage under build out conditions is 59.1 MG. Thus, the City would need to construct about 45 MG of new storage capacity by the time the City reaches build-out conditions. 7.3.1 2015 The near-term storage requirements of at least 5.2 MG could be met by constructing one 5-MG reservoir in addition to the 5-MG reservoir recommended in Chapter 6 for existing system improvements. This would provide some additional flexibility and capacity for a few years beyond 2015. It is recommended that the City construct the following reservoirs: 5 MG at the WTP site by 2015 (along with the construction of the new 21-mgd WTP). 5 MG at the La Brucherie site, beginning construction by 2015. Both locations have sufficient space to accommodate a new 5-MG tank and the existing pipeline and booster station infrastructure can be utilized. The need for additional booster station capacity is discussed in Section 7.4. 7.3.2 Build-Out To meet the storage requirements under build-out conditions, the City would need to install 35 MG of storage in addition to the 10 MG recommended for year 2015. It is recommended that the City purchase two or three new sites to accommodate additional ground storage and provide an even distribution of storage and booster stations throughout the SOI. A potential scenario for new storage could be: 15 MG at a new site in the SE part of the City (e.g., three 5-MG tanks), located near the intersection of Frontage Road and Pitzer Road. 10 MG at a new site in the NE part of the City (e.g., two 5-MG tanks), located near the intersection of Cooley Road and Villa Road. 10 MG at a new site in the NW part of the City (e.g., two 5-MG tanks), located near the intersection of Cross Road and Villa Avenue. The reservoir locations assumed for the hydraulic modeling are shown on Figure 7.5. It should be noted that these reservoir and PS locations are hypothetical locations that are subject to change based on actual land acquisition opportunities. It is recommended that the City purchase parcels with sufficient space to accommodate multiple small (e.g., 5-MG) tanks, versus one large (10-MG or more) tank. Multiple small tanks provide operational flexibility and reliability for cleaning and repairs. It also provides the opportunity to phase the construction and capital cost of storage facilities, while avoiding water quality problems in oversized tanks. As the City s growth rate is expected to be slow to moderate, it is likely that it is more cost-effective to phase the construction cost compared to the economies of scale that large reservoirs bring. FINAL - February 13, 2008 7-9 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

30'' 24'' 24'' 24'' 18'' 30'' 20'' 24'' 30'' 24'' Legend Sphere of Influence 30'' 30'' 24'' 24'' 24'' 24'' 20'' 36'' 36'' 36'' 36'' 24'' 36'' 36'' 36'' City Limits Existing Facilities Reservoir Pump Station Recommended Facilities [ WTP (21-mgd) [ WTP (25-mgd) Reservoir* Pump Station* 12-inch Pipes 18 and 20-inch Pipes 24-inch Pipes 30-inch Pipes 36-inch Pipes Existing Pipes * Potential Locations (subject to change) 36'' Feet 0 3,000 6,000 FIGURE 7.5 RECOMMENDED FUTURE SYSTEM PIPELINES AND FACILITIES WATER MASTER PLAN CITY OF EL CENTRO AÌ Cooley Rd Dogwood Rd NW Site 2 New 5-MG Tanks (10 MG) New 300 hp PS Fourth St Clark Rd A³ La Brucherie Rd Austin Rd Treshill Rd NE Site 2 New 5-MG Tanks (10 MG) New 300 hp PS Cruickshank Rd Villa Rd 24'' La Brucherie Site Reservoir (5 MG) and 400 hp PS Evan Hewes Hwy New 5-MG Tank New 150 hp PS Orange Ave 24'' SE Site 3 New 5-MG Tanks (15 MG) New 400 hp PS Ross Rd 20''!"_$!"_$ 36'' [ [ Danenberg Rd 36'' McCabe Rd AÌ Existing Facilities: 3 Reservoirs (10 MG) 800 hp PS A³ New 21-mgd WTP New 25-mgd WTP New 5-MG Tank New 900 hp PS

7.4 PUMP STATION CAPACITY EVALUATION The PS capacity evaluation consists of a comparison of the existing pumping capacity and the required pumping capacity per the following evaluation criteria: Normal Conditions: Meet PHD with the largest pump unit out of service. Power Outage: Meet MDD with backup power only. Earthquake: Meet ADD with the largest PS out of service. 7.4.1 2015 The MDD projected for 2015 is 10,300 gpm, while the projected PHD is 17,400 gpm (see Table 7.1). As described in Chapter 2, the City has one PS at the WTP site with four 4,000-gpm pump units and one PS at the La Brucherie PS site with two 4,000-gpm pump units. As described in Chapter 6 the City has full backup power at the WTP PS site and La Brucherie PS site to keep all pump units operational at all times. The pump station capacity evaluation for 2015 conditions is summarized in Table 7.3. As shown in Table 7.3, all PS requirements are met. Therefore, no additional recommendations are made. Table 7.3 Pump Station Capacity Evaluation - 2015 Water System Master Plan City of El Centro Evaluation Condition Available Capacity Meet PHD with largest 20,000 (1) unit out of service (1) Total Required Capacity Difference Unit 17,400 2,600 gpm Power outage (2) 20,000 (2) 10,300 9,700 gpm Earthquake (3) 8,000 (3) 6,500 1,500 gpm Notes: (1) One unit is assumed to be out of service at the WTP PS. The remaining capacity consists of 3 x 4,000 gpm at the WTP PS and 2 x 4,000 gpm at the La Brucherie PS. (2) During a system-wide power outage, all pumping supplies are operational, minus one unit out of service. (3) It is assumed that the entire PS at the WTP is destroyed, while all units at the La Brucherie PS are assumed to remain operational. 7.4.2 Build-Out The MDD and PHD for build-out conditions are 31,000 gpm and 52,400 gpm, respectively (see Table 7.1). As described above, the City has full backup power at the WTP PS site and La Brucherie site to keep all pump units operational at all times. The pump station FINAL - February 13, 2008 7-11 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

capacity evaluation for build-out conditions using these assumptions is summarized in Table 7.4. Table 7.4 Evaluation Condition Pump Station Capacity Evaluation - Build-Out Water System Master Plan City of El Centro Available Capacity Total Required Capacity Difference Unit Meet PHD 20,000 (1) 52,400-32,400 gpm Power Outage 20,000 (2) 31,000-11,000 gpm Earthquake 8,000 (3) 19,400-11,400 gpm Notes: (1) One unit is assumed to be out of service at the WTP PS. The remaining capacity consists of 3 x 4,000 gpm at the WTP PS and 2 x 4,000 gpm at the La Brucherie PS. (2) During a system-wide power outage, all pumping supplies are operational, minus one unit out of service. (3) It is assumed that the entire PS at the WTP is destroyed, while all units at the La Brucherie PS are assumed to remain operational. As shown in Table 7.4, none of the pumping capacity requirements are met. The following recommendations are made to meet the criteria and provide sufficient pumping capacity to meet PHD, power outage, and earthquake conditions: Construct a 800-hp PS at the proposed 25-mgd WTP site (see Section 7.5). It is assumed that this station will include six 4,000-gpm pump units, however, the exact pump configuration can be modified during preliminary design. Add a third pump unit of 4,000 gpm to the La Brucherie PS. This station has a dedicated space for a future pump and therefore, no additional PS building or yard piping would be required. The capacity of this pump is approximately 150 hp. Construct a 400-hp PS at the new reservoir site in the SE part of the City. It is assumed that this station will include three 4,000-gpm pump units, however, the exact pump configuration can be modified during preliminary design. Construct a 300-hp PS at the new reservoir site in the NE part of the City. It is assumed that this station will include two 4,000-gpm pump units, however, the exact pump configuration can be modified during preliminary design. Construct a 300-hp PS at the new reservoir site in the NW part of the City. It is assumed that this station will include two 4,000-gpm pump units, however, the exact pump configuration can be modified during preliminary design. The total system-wide pumping capacity with these recommendations is 80,000 gpm with all units on and 52,000 gpm with the largest unit out of service at each PS. It is assumed FINAL - February 13, 2008 7-12 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

that the projected PHD at build-out (52,400 gpm) can be met with six pumps out of service by operating some pumps at slightly lower discharge pressures. The total pumping capacity at the WTPs (16,000 gpm at the 21-mgd WTP and 24,000 gpm at the 25-mgd WTP) is 40,000 gpm with all units on and 32,000 gpm with the largest unit out of service in each PS. This is sufficient to supply the projected MDD at build-out conditions. In addition, it is recommended to install the following backup power facilities to provide operational flexibility and an even supply distribution during system-wide power failures: 150 hp of backup power at the La Brucherie PS for the new 4,000-gpm pump unit, resulting in a total backup power capacity of 12,000 gpm. 400 hp of backup power at the SE PS for all three 4,000-gpm pump units, with a total backup power capacity of 12,000 gpm. 300 hp of backup power at the NE PS for both 4,000-gpm pump units, with a total backup power capacity of 8,000 gpm. 300 hp of backup power at the NW PS for both 4,000-gpm pump units, with a total backup power capacity of 8,000 gpm. 800 hp of backup power at the 25-mgd WTP for all six 4,000-gpm pump units, with a total backup power capacity of 24,000 gpm. 7.5 WATER SUPPLY EVALUATION The future system water supply evaluation consist of the evaluation of: 1. Outage of the largest supply source. 2. Power outage. 3. Earthquake. To avoid redundant recommendations, it is assumed that recommendations made in Chapter 6 and in Sections 7.3 and 7.4 would be incorporated for the supply analysis. These recommendations are: 5-MG storage reservoir at the existing WTP site. 5-MG storage at the La Brucherie site. 45-MG storage at the three new sites in the SE, NE, and NE part of the City. Four new pump stations with a combined capacity of 52,000 gpm at the new 25-mgd WTP site and the three new sites in the SE, NE, and NW part of the City. One new pump at the La Brucherie PS with a capacity of 4,000 gpm. FINAL - February 13, 2008 7-13 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

In addition, it is assumed that the City will construct another WTP after 2015 with a total capacity of 25 mgd to meet the projected MDD for build-out conditions (44.7 mgd). With this second WTP, the total supply capacity would be 46 mgd. Similar to the 21-mgd WTP, it is assumed that this 25-mgd WTP will be constructed with enough redundancy and backup power to operate at a minimum of 50 percent capacity (12.5 mgd). Other assumptions and findings of these analyses are described in the following subsections and are summarized in Tables 7.5 and 7.6. 7.5.1 Largest Source Out of Service The evaluation criterion states that the City should be able to meet MDD for 7 days with the largest source out of service. 7.5.1.1 2015 The largest and only source of supply in 2015 is the City s new 21-mgd WTP. Thus, storage is the only available source of water when the WTP is out of service. The City s projected MDD for year 2015 is 14.8 mgd, which equals 103.6 MG over 7 days. With the proposed storage tanks in place by 2015, the total available storage is 25.0 MG when all tanks are completely full. However, it is assumed that all the reservoirs are only about 70 percent full at the time of any emergency, resulting in 17.5 MG of supply. Based on the comparison of the required and available supplies, it can be concluded that the City will have a supply deficit of about 86.1 MG when the WTP is out of service for 7 days. The supply deficit is reduced to 12.6 MG if the new WTP would have enough redundancy to be able to operate at 50 percent capacity. If the 21-mgd WTP can operate but the source water is contaminated, the plant can use the raw water storage ponds (52.5 MG) and reduce the supply deficit to 33.6 MG. It is recommended that the new 21-mgd WTP be equipped with enough backup power and redundancy to be able to produce at least 10.5 mgd during a major breakdown. This will allow the City to meet the 2015 ADD, while providing sufficient supplies to meet MDD for approximately 80 hours (3.3 days). During this time, the City can issue public water conservation notifications to its customers to reduce demands sufficiently, even during the high demand months in the summer. If the WTP outage is not resolved within 4 days (assuming that the WTP can operate at 50 percent capacity), then the City could use the supplies from the raw water ponds and bypass the plant to continue water service and fire flow protection. The raw water ponds can be directly supplemented from the canal through the raw water PS to continue a raw water supply for as long as needed. As mentioned in Chapter 6, boil-water-notices would need to be issued to inform the City s customers and the Department of Health Services. FINAL - February 13, 2008 7-14 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

FINAL - February 13, 2008 7-15 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc Table 7.5 Water Supply Evaluation 2015 Conditions Water System Master Plan City of El Centro Supply Condition Required Supply (MG) Available Supply from WTP Site (MG) Available Supply from La Brucherie Site (MG) Total Available Supply (MG) Surplus/ Deficit (MG) Largest source (WTP) out of service 103.6 10.5 7.0 17.5-86.1 (1) System-wide power outage 3.7 5.8 0.0 5.8 2.1 Earthquake - destroying the WTP site facilities 90.7 0.0 7.0 7.0-83.7 (1) Notes: (1) This deficit can be met by the temporary distribution of raw water from one of the IID canals. Boil-water notifications would need to be sent to the City s customers and the Department of Health Services. The City has access to multiple IID canals within a few miles of the WTP site. Temporary aboveground pipelines could be installed if the canal adjacent to the WTP would not be available.

FINAL - February 13, 2008 7-16 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc Table 7.6 Water Supply Evaluation Build-Out Conditions Water System Master Plan City of El Centro Supply Condition Required Supply (MG) Available Supply from WTP Site (MG) Available Supply from La Brucherie site (MG) Available Supply from New Sites (MG) Total Available Supply (MG) Surplus/ Deficit (MG) Largest source out of service 312.7 157.5 7.0 28.0 192.5-120.2 (1) System-wide power outage 11.2 5.8 4.3 7.6 17.6 6.5 Earthquake - destroying the WTP site facilities 273.6 304.5 7.0 28.0 339.5 65.9 Notes: (1) This deficit can be met by the temporary distribution of raw water from one of the IID canals. Boil-water notifications would need to be sent to the City s customers and the Department of Health Services. The City has access to multiple IID canals within a few miles of the WTP site. Temporary aboveground pipelines could be installed if the canal adjacent to the WTP would not be available.

The hydraulic model was used to verify the system pressures under this scenario. The model results show that the system pressures range from 53 to 62 psi, as long as enough supply is available. 7.5.1.2 Build-Out The largest and only source of supply at build out is the City s new 25-mgd WTP. Thus, the City would have the 21-mgd WTP and storage available when the future proposed plant is out of service. The City s MDD projected demand for build-out is 44.7 mgd, which equals 312.7 MG over 7 days. With the proposed storage tanks in place, the total available storage is 65.0 MG when all tanks are completely full. However, it is assumed that all the reservoirs are only about 70 percent full at the time of any emergency, resulting in 45.5 MG of supply. Based on the comparison of the required and available supplies, it can be concluded that the City will have a supply deficit of about 120.2 MG when the WTP is out of service for 7 days. This deficit is reduced to 32.7 MG if the new 25-mgd WTP would have enough redundancy to be able to operate at 50 percent capacity. It is therefore recommended that the new 25-mgd WTP also be equipped with enough backup power and redundancy to be able to produce at least at 12.5 mgd during a major breakdown. This will allow the City to meet the existing ADD, while providing sufficient supplies to meet MDD for approximately 50 hours. During this time, the City can issue public water conservation notifications to its customers to reduce demands sufficiently, even during the high demand months in the summer. The hydraulic model was used to verify the system pressures under this scenario. The results predict that the pressures will range from 46 to 60 psi, as long as enough supply is available. 7.5.2 Power Outage The evaluation criterion states that the City should be able to meet MDD for 6 hours during a system-wide power outage. 7.5.2.1 2015 The City s projected MDD for 2015 is 14.8 mgd, which equals 3.7 MG over 6 hours. As discussed in Section 6.4 and Section 7.4, it is recommended that the City construct sufficient backup power facilities by 2015 to provide for: 50 percent production capacity at the 21-mgd WTP (10.5 mgd). 16,000 gpm at the 21-mgd WTP PS (this is assumed to be the existing WTP PS and backup power). FINAL - February 13, 2008 7-17 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

4,000 gpm at the La Brucherie PS (in addition to the existing backup power for 8,000 gpm). The available pumping capacity with a system-wide power outage is 28,000 gpm, which equals 10.10 MG over 6 hours. As this exceeds the MDD of 10,400 gpm, it can be concluded that the City has sufficient pumping capacity with the recommended backup power facilities to meet the criterion. However, the available supplies also need to be verified by comparing the pumping capacity at each site with the available supply. The available supply at the 21-mgd WTP operating at 50 percent capacity is 13.1 MG. This includes 10.5 MG from storage and 2.6 MG of treated water in 6 hours. This exceeds the pumping capacity of 5.8 MG in 6 hours. The available supply at the La Brucherie site is 7.0 MG from storage, which exceeds the pumping capacity of 4.3 MG in 6 hours. Thus, the pumping capacity governs at both locations. As the available pumping capacity (10.1 MG) exceeds the required supply of 3.6 MG, it can be concluded that this evaluation criterion is met. 7.5.2.2 Build-Out The City s projected MDD for build-out conditions is 44.7 mgd, which equals 11.1 MG over 6 hours. As discussed in Section 6.4 and Section 7.4, it is recommended that the City construct sufficient backup power facilities by build-out to provide for: 50 percent production capacity at the 21-mgd WTP (10.5 mgd). 50 percent production capacity at the 25-mgd WTP (12.5 mgd). 16,000 gpm at the 21-mgd WTP PS. 12,000 gpm at the La Brucherie PS. 12,000 gpm at the new facility in the SE part of the City. 8,000 gpm at the new facility in the NW part of the City. 8,000 gpm at the new facility in the NE part of the City. Thus, the available pumping capacity with a system-wide power outage is 56,000 gpm or 80.6 mgd. This equals 20.1 MG over 6 hours. As this exceeds the MDD of 11.2 MG over 6 hours, it can be concluded that the City has sufficient pumping capacity with the recommended backup power facilities to meet the criterion. However, the available supplies also need to be verified by comparing the pumping capacity at each site with the available supply. The available amount from storage is determined as 70 percent of the total storage volume to account for typical tanks levels. The available supply at the 21-mgd WTP operating at 50 percent capacity is 13.1 MG, which includes 10.5 MG from storage and 2.6 MG of treated water in 6 hours. This exceeds the pumping capacity of 16,000 gpm or 5.8 MG in 6 hours. FINAL - February 13, 2008 7-18 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

The available supply at the La Brucherie site is 7.0 MG from storage. This exceeds the pumping capacity of 12,000 gpm or 4.3 MG in 6 hours. The available supply at the new facility in the NE part of the City is 10.5 MG from storage. This exceeds the pumping capacity of 12,000 gpm or 4.3 MG in 6 hours. As the available supply at each site exceeds the pumping capacity, the PS governs at all locations. The available pumping capacity (14.4 MG) exceeds the required supply of 11.0 MG. Thus, it can be concluded that this evaluation criterion is met. 7.5.3 Earthquake The evaluation criterion states that the City should be able to meet MinDD for 14 days in case of an earthquake. It is assumed that an earthquake would destroy all the facilities at the largest WTP. This situation is evaluated for both 2015 and build-out conditions. 7.5.3.1 2015 The City s MinDD projected for 2015 is 6.5 mgd, which equals 90.7 MG over 14 days. The only available supply after an earthquake that damages the facilities at the WTP site is the storage at the La Brucherie site. The available supply in storage is 7.0 MG, which can easily be pumped by the existing PS (8,000 gpm or 11.5 mgd). The total supply deficit accumulated over 14 days is 83.7 MG. Additional ground storage of treated water is not cost-effective to address this deficiency. Due to the City s single source of supply, the system is vulnerable to extreme emergencies such as earthquakes. Public notices would need to be issued to promote water conservation. Water could be trucked to the remaining storage facilities to provide a continued minimum amount of supply. A detailed emergency response plan for WTP repairs should be kept up to date to facilitate fast repairs. As stated in Section 7.5.1, the City could temporarily use raw water from the IID canal by pumping it directly into its distribution system after sending out boil-water notifications. Raw water could be obtained from any of the surrounding canals through temporary aboveground pipelines if the canal adjacent to the WTP would not be accessible. The hydraulic model was used to verify the system pressures under this scenario. The model results show that the system pressures range from 52 to 66 psi, as long as enough supply is available. It is estimated that the supplies would be depleted after approximately 25 hours. 7.5.3.2 Build-Out The City s MinDD projected for build-out conditions is 19.5 mgd, which equals 273.6 MG over 14 days. The most severe scenario would be the destruction of the facilities at the largest (25-mgd) WTP site. It is assumed that the 21-mgd WTP would remain operational. FINAL - February 13, 2008 7-19 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

In addition, water supply can be obtained from storage at the 21-mgd WTP site, the La Brucherie site, and the three new sites in the SE, NE, and NW part of the City. The available supply from storage, using 70 percent of the total capacity, is 45.5 MG, which can easily be pumped in 14 days by the available pump stations (56,000 gpm or 80.6 mgd). With the 21-mgd WTP operational, the entire MinDD can be met. 7.6 SUMMARY OF RECOMMENDATIONS The future system analysis identified the following improvements: 2015 Improvements WTP-1: new 21-mgd WTP at the existing WTP site (this plant is planned to start construction in 2008). NTP-1 thru NTP-2: 0.6 mile of 20-inch diameter near-term backbone pipes to serve the 2015 developments. NTP-3: 0.3 mile of 36-inch diameter near-term backbone pipes to serve the 2015 developments. NTP-4 thru NTP-15: 3.5 miles of 12-inch diameter near-term backbone pipes to serve the 2015 developments. NTP-16: 0.2 miles of 18-inch diameter pipeline to complete the 18-inch pipeline distribution line from the WTP to the La Brucherie Reservoir. HP-1: 300 hp of backup power at the 21-mgd WTP. Build Out Improvements WTP-2: new 25-mgd WTP (in addition to the proposed 21-mgd WTP). FP-1: 56 miles of 12-inch diameter future pipelines for the future backbone system. FP-2: 1 mile of 20-inch diameter future pipelines for the future backbone system. FP-3: 3.8 miles of 24-inch diameter future pipelines for the future backbone system. FP-4: 2.3 miles of 30-inch diameter future pipelines for the future backbone system. FP-5: 4.6 miles of 36-inch diameter future pipelines for the future backbone system. T-2 thru T-9: 45 MG of reservoir storage at La Brucherie and three new sites in the NW, NE, and SE part of the City. PS-1 thru PS-5: five PS projects at five different locations with a combined capacity of 2,050 hp. HP-2 thru HP-7: 2,350 hp of backup power at the 25-mgd WTP and PS, La Brucherie PS, NE PS site, NW PS site, and SE PS site. FINAL - February 13, 2008 7-20 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch07.doc

Chapter 8 CAPITAL IMPROVEMENT PROGRAM This chapter presents the recommended Capital Improvement Program (CIP) for the City of El Centro (City) water distribution system. The program is based on the evaluation of the City s water distribution system and on the recommended projects described in the previous chapters. The CIP has been prepared to assist the City in planning and design of the water system improvements required by 2015. The sizing of improvements is based on the ultimate sizing requirements at build out conditions. 8.1 COST ESTIMATING The discussion of cost estimating includes the following topics: Level of accuracy. Contingencies. Unit construction costs. 8.1.1 Level of Accuracy The cost estimates presented in this CIP are prepared for general master planning purposes and for guidance in project evaluation and implementation. The actual project costs will depend on actual labor and material costs, competitive market conditions, final project scope, implementation schedule, and other variable factors such as: preliminary alignments generation, investigation of alternative routings, and detailed utility and topography surveys. The American Association of Cost Engineers defines three types of cost estimates: An Order of Magnitude Estimate for Master Plan Studies. This is an approximate estimate made without detailed engineering data. It is normally expected that an estimate of this type would be accurate within +50 percent to -30 percent. A Budget Estimate for Predesign Study. A budget estimate is prepared with the use of flow sheets, layouts, and equipment details. It is normally expected that an estimate of this type would be accurate within +30 percent to -15 percent. A Definite Estimate (Engineer's Estimate) for time of contract bidding. This estimate is prepared from very defined engineering data. The data includes fairly complete plot plans and elevations, soil data, and a complete set of specs. It is expected that an engineer s estimate would be accurate within +15 to -5 percent. Costs developed for this master plan should be considered "order of magnitude" and have an expected accuracy range of +50 percent to -30 percent. FINAL - February 13, 2008 8-1 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch08.doc

8.1.2 Contingencies Since knowledge about site-specific conditions of each proposed project is limited at the master planning stage, a contingency will be applied to the construction cost to account for unforeseen events and unknown conditions. Other project related costs include engineering, design, construction management, and legal and administrative costs. Three types of mark-ups are used for the preparation of the capital cost estimates. These mark-ups are summarized in Table 8.1. Table 8.1 Contingency Unit Construction Costs Mark-ups Water System Master Plan City of El Centro Category Mark-up (%) Engineering, Design and Construction Mgmt Legal and Administration Total Capital Cost 30% of Construction Cost (CC) 15% of CC + Contingency 10% of CC + Contingency 162.5% of CC The capital cost, in dollars, for the proposed improvement projects consists of the construction cost plus the contingencies listed in Table 8.1 As shown, the total capital cost is 162.5 percent of the construction cost. 8.1.3 Unit Construction Cost Construction cost estimates are opinions developed based on costs obtained from industry manufacturers bid tabulations, cost curves, previous studies, and Carollo Engineers experience on similar projects. All estimates presented herein have been adjusted to an Engineering News Record (ENR) index of 9,216 (October 2007). This ENR index is used to adjust construction costs for inflation and current business conditions. For example if a reservoir will be constructed in five years, its cost should be adjusted for inflation by the ratio of the anticipated ENR index in 2012 to the current ENR index. Assuming a year 2012 index of 9,600 and a current cost of $1 million, the future cost of the reservoir will be $1,040,000 ($1,000,000 x 9,600/9,216). The ENR Cost Index is calculated periodically based on various industry factors that adjusts cost and include factors such as inflation for material costs and labor costs. The unit construction costs used in this master plan are presented in Table 8.2. FINAL - February 13, 2008 8-2 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch08.doc

Table 8.2 Pipelines Storage Reservoirs Pump Stations Back-up Power Unit Construction Costs Water System Improvements Water System Master Plan City of El Centro Diameter Unit Cost ($/lineal ft) 8 inches $115 12 inches $137 16 inches $166 18 inches $186 20 inches $206 24 inches $264 30 inches $292 36 inches $371 Volume (MG) Unit Cost ($/gallon) <1 $2.30 1-3 $1.70 3-5 $1.40 5-10 $1.20 Capacity (hp) Unit Cost ($/hp) <100 $6,770 101-500 $4,550 Capacity (hp) Unit Cost 100 $150,000 150 $225,000 200 $300,000 300 $450,000 400 $600,000 8.2 SUMMARY OF IMPROVEMENTS The existing and future system improvements discussed in Chapters 6 and 7 are presented in Table 8.3. The category abbreviations presented in this table are used to identify specific projects in Table 8.6 and Figure 8.1. FINAL - February 13, 2008 8-3 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch08.doc

Table 8.3 Summary of System Improvements Water System Master Plan City of El Centro Category Improvement Description Quantity Unit Existing System FF Fire flow improvements 4 miles PB Pipe break improvements 1 miles Age Replacement of old pipelines 14 miles T Construction of 1 new tank 5 MG Future System NTP Near-term pipeline improvements (by 2015) 5 miles FP Future pipeline improvements (after 2015) 67 miles T Construction of 8 new tanks (5 MG each) 40 MG S Supply improvements two new WTPs (1) 46 mgd PS Pump station improvements 5 new PSs 2,050 hp HP Back-up power for 5 new PSs and two WTPs (1) 2,650 hp Notes: (1) This includes the 21-mgd WTP that will begin construction in 2008 and a future 25-mgd WTP. As shown in Table 8.3, the total length of recommended existing system pipe improvements is approximately 19 miles. Additional improvements include the installation of one 5-MG tank. The total length of recommended future system pipes is approximately 72 miles. It should be noted that these pipelines are limited to the backbone distribution network surrounding approximately every quarter square mile block (as shown on Figure 8.1). The in-tract pipelines and service laterals are not included in this CIP, as these are typically installed by the developers and because these pipelines would require the knowledge of the future parcel and street layout. Combined with the existing system improvements, the total length of pipe installations is approximately 91 miles. Additional future system improvements include 46 mgd of new treated water supply capacity (21 mgd from the future WTP and 25 mgd from a second WTP), 5 pump stations with a total capacity of 2,050 hp, and a total of 2,650 hp of back-up power for the 21-mgd WTP (300 hp), 25-mgd WTP (300 hp), 25-mgd WTP PS (900 hp), La Brucherie Reservoir Site PS (150 hp), NE Reservoir Site PS (300 hp), NW Reservoir Site PS (300 hp), and SE Reservoir Site PS (400 hp). FINAL - February 13, 2008 8-4 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch08.doc

8.3 PHASING OF IMPROVEMENTS The recommended improvements are phased based on the projected water demands and the corresponding system needs. All projects are phased using the following three categories: Existing system improvements (Construction from present to year 2015). 2015 growth (Construction from year 2010 to 2015). Build out growth (Construction after year 2015). The following methodology is used for the project phasing: Fire Flow Pipelines: All of the fire flow deficiencies are located in areas designated as commercial, public, or industrial land use and therefore are all considered high priority. If deficiencies were located in residential areas, these would have been given a medium or low priority depending on the number of parcels impacted by the deficiency. The phasing of fire flow improvements is therefore solely based on residual pressures. Projects with the largest pressure deficiencies are scheduled first, while projects that address only minor deficiencies are scheduled last. The priorities of the FF improvements are shown by year in Table 8.6. Pipe-Break Pipelines: The phasing of pipe installations to mitigate the affects of pipeline breaks is prioritized based on the number of demand nodes affected by the break. For example, the installation of PB-1 has the highest priority as over 120 demand nodes are cut off from water supply given a pipe break on Danenberg Road (break 9). The phasing of the remaining PB improvements is listed by year in Table 8.6. Age Replacements: The estimated 14 miles of age replacements are scheduled to be installed by the year 2015. It should be noted that these improvements consist of 50 percent of the pipelines with unidentified year of installation. The actual location and prioritization of these replacements should be determined with a separate study and field coupon testing to access the condition of individual pipelines. Near-term Pipelines: The pipelines that supply water to the Lerno, Gillett, and Waterford developments are all scheduled to be installed by the year 2015. This location of these pipelines is subject to change as the phasing of the parcels within these developments is unknown at this time. In addition, a short section of 18-inch diameter pipeline that connects two existing 18-inch diameter pipelines (NTP-16) between the WTP to La Brucherie site is scheduled for installation by year 2015. Water Treatment Plants: The new 21-mgd WTP is scheduled to begin construction in 2008 and is therefore phased in the 2015 growth category. The new WTP will replace the existing WTP and will benefit both existing and future users, and will have enough capacity to meet the MDD through approximately year 2050. The recommended 25- FINAL - February 13, 2008 8-5 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch08.doc

mgd WTP is solely required for future users and is sized to meet MDD under build out conditions. This plant (or a portion of this plant) is not required until year 2050 and is therefore phased in the build out growth category. Storage Tanks: The construction of a 5-MG tank at the existing WTP is high priority and phased to be installed before 2015 to meet existing storage requirements. The other eight tanks are not required until after 2015. Pump Stations: The existing pump stations have sufficient capacity to meet the requirements through year 2015. Thus, additional pump stations are phased after 2015. Back-up Power: Since there is currently full back-up power at both the WTP and La Brucherie PSs, no additional back-up power is required for the existing system. However, it is recommended that additional back-up power be installed at the new treatment plants and pump stations. The phasing of these diesel-generator back-up power facilities coincides with the phasing of the proposed PSs and WTPs. It should be noted that the actual sequence of the construction of the proposed PSs and storage facilities at the new sites in the NE, SE, and SW part of the City will be dependent upon the actual phasing of developments. The implementation schedule of these new sites will also determine the phasing of the transmission mains that connect these new facility sites through the transmission main loop shown on Figure 8.1. It is recommended that the City start the process of land acquisition for these sites now, before land costs further increase. Phasing of the pipelines and facilities is shown on Figure 8.1, while a detailed CIP is presented in Table 8.6. 8.4 COST ESTIMATES The cost of the CIP is estimated by project using the cost estimating assumptions discussed in Section 8.1. These cost estimates by project (see Table 8.6) are used to create two types of summary tables: a summary by facility type (Table 8.4) and a summary by user type (Table 8.5). FINAL - February 13, 2008 8-6 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch08.doc

Table 8.4 Facility Type Water System CIP Summary - by Facility Water System Master Plan City of El Centro 2015 ($M) After 2015 ($M) Total ($M) Pipelines $11.8 $104.6 $116.4 Pump Stations $0.0 $16.7 $16.7 Reservoirs $9.8 $78.0 $87.8 Water Supply $34.9 $54.5 $89.3 Grand Total $56.4 $253.8 $310.1 As shown in Table 8.4, the total CIP to build out is $310 million, while the cost associated with projects to be constructed by 2015 is estimated at $56 million. This equates to $8 million per year in the period 2008 to 2015. As shown in Figure 8.2, the cost of reservoir and water supply improvements are similar, each contributing nearly 30 percent of the total CIP, while the cost of pipeline improvements is about 38 percent of the total CIP. The summary by user type differentiates the costs between projects that benefit existing customers and projects that are required to supply future customers. This differentiation is important as it is related to the financing mechanisms used to implement the projects. The cost allocated to existing users is typically paid through water rate increases, while the cost associated with growth (future users) is typically paid through developer impact fees. Projects that address existing system deficiencies are 100 percent allocated to the existing user category, while projects that are not required until after year 2015 are 100 percent allocated to the future user category. Some projects benefit both existing and future customers and those are prorated between these two user categories based on the demand served. The cost allocation between existing and future customers for each project is listed in Table 8.6. FINAL - February 13, 2008 8-7 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch08.doc

FF-2 8'' 8'' 8'' FF-12 8'' FF-1 24'' 8'' 8'' 18'' 8'' 8'' 8'' 24'' FF-7 8'' FF-3 8'' FF-14 PB-3 FF-16 FF-10 18'' 30'' 30'' 30'' FF-8 FF-17 30'' 20'' 36'' 36'' Legend Sphere of Influence 36'' 24'' 24'' 36'' 36'' 20'' 36'' 24'' City Limits Existing Facilities Reservoir Pump Station 30'' Existing Pipes Recommended Facilities WTPs [ [ 24'' Reservoirs Existing System Improvements Build Out Improvements* Existing System Improvements 36'' 24'' Build Out Improvements* 24'' Pump Stations Build Out Improvements* T-3, PS-2 Existing System Improvements 2015 Improvements Build Out Improvements CIP ID's * Potential Locations (subject to change) Feet 0 3,000 6,000 FIGURE 8.1 PHASING OF RECOMMENDATIONS WATER MASTER PLAN CITY OF EL CENTRO 36'' AÌ Cooley Rd Dogwood Rd NW Site 2 New Fourth St Clark Rd A³ La Brucherie Rd Austin Rd Treshill Rd 5-MG Tanks (10 MG) (T-6, T-7) New 300 hp PS (PS-3) NE Site 2 New 5-MG Tanks (10 MG) (T-8, T-9) New 300 hp PS (PS-4) Cruickshank Rd NTP 9-11 FF-2 Villa Rd 24'' FF-11 8'' 8'' La Brucherie Site Reservoir (5 MG) and 400 hp PS 8'' Evan Hewes Hwy 8'' FF-4 FF-15 New 5-MG Tank (T-2) New 150 hp PS (PS-1) NTP 12-15 FF-13 NTP-16 Orange Ave SE Site 3 New 5-MG Tanks (15 MG) (T-3, T-4, T-5) New 400 hp PS (PS-5) FF-6 FF-5 8'' FF-9 Ross Rd 20'' 12"!"_$!"_$ 36'' NTP 1-8 [ [ Danenberg Rd PB-2 PB-1 36'' New WTP (21-mgd) WTP-1 New WTP (25-mgd) McCabe Rd WTP-2 AÌ A³ Existing Facilities: 3 Reservoirs (10 MG) 800 hp PS New 5-MG Tank (T-1) New 900 hp PS (PS-2)

Table 8.5 Facility Type Existing Users Water System CIP Summary - by User Type Water System Master Plan City of El Centro 2015 ($M) After 2015 ($M) Total ($M) Pipelines $5.4 $8.7 $14.0 Reservoir $9.8 $0.0 $9.8 Supply $22.4 $0.0 $22.4 Subtotal $37.5 $8.7 $46.2 Future Users Pipelines $6.4 $95.9 $102.3 Pump Stations $0.0 $16.7 $16.7 Reservoirs $0.0 $78.0 $78.0 Supply (1) $12.5 $54.5 $67.0 Subtotal $18.9 $245.1 $264.0 Grand Total $56.4 $253.8 $310.1 Notes: (1) Supply includes new WTPs and back-up power facilities. (2) All costs are in 2007 dollars (no escalation). As shown in Table 8.5, the total estimated cost allocated to the existing users is $46 million, while the estimated cost allocated to future system users is approximately $264 million. The estimate cost of the projects to be constructed by 2015 is $56 million, which equates to $8 million per year. Nearly half of these costs are associated with the new 21-mgd WTP ($25 million), which is planned to start construction in 2008. It should be noted that the 21- mgd WTP is already funded at the current rate, however it is included in this CIP for budgeting purposes and care should be taken to not double-count the costs related to this plant. Since this plant is replacing the existing 15-mgd WTP, 66 percent of the costs is allocated to existing users, while the remaining 34 percent is allocated to future users. This 66 percent is calculated by dividing the existing MDD (13.8 mgd) by the capacity of the new WTP (21 mgd). A chart of the costs by facility type is shown on Figure 8.2, and a detailed breakdown of the CIP is presented in Table 8.6. FINAL - February 13, 2008 8-9 H:\client\City_ElCentro_PAS\04 Reports\04.2 Final\04.2d Final to Client\Ch08.doc

20-ElCentro2-08F8.2-7619 A00.cdr Supply $89.3 M (29%) Pipelines $116.4 M (38%) Reservoirs $87.8 M (28%) Note: Supply includes new WTPs and back-up power improvements. Pump Stations $16.7 M (5%) DISTRIBUTION OF CAPITAL COST FIGURE 8.2 WATER MASTER PLAN CITY OF EL CENTRO