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HomeMy WebLinkAbout2000-03-20 City Council (22)City of Palo Alto City Manager’s Report TO:THE HONORABLE CITY COUNCIL FROM:CITY MANAGER DEPARTMENT: UTILITIES DATE: SUBJECT: MARCH 20, 2000 CMR:141:00 PROPOSED FY 2000/2005 WATER CAPITAL IMPROVEMENT PROGRAM This is an informational report and no Council action is required. The purpose of this report is to alert Council that an additional $15.7 million dollars ( 1999 dollars) is being proposed by staffin the FY 2000-05 Water Capital Improvement Program to improve the emergency supply and fire fighting capabilities of the City’s water system. Improvements will also be constructed to improve normal water system operations and to prepare the distribution system for disinfectant conversion from chlorine to chloramine disinfectant in 2003. BACKGROUND The need to improve Palo Alto’s emergency water supply facilities has been identified for almost two decades. In July 1982, the City of Palo Alto authorized James Montgomery Consulting Engineers, Inc. to prepare an engineering report on the City’s water system. This report, completed in 1983, recommended that a 2 million gallon storage reservoir be built and the City maintain 5 existing wells in service, as standby emergency water sources but not ;provide additional treatment of the well water at that time. The James Montgomery Report also recommended that the City increase its storage and pumping facilities to meet Palo Alto’ peak water demands. The more costly capital improvement recommendations for reservoir construction from the James Montgomery Report were not pursued because of the financial impact on the water system. In 1998, the Utilities Department hired Carollo Engineers to perform the "Water Well, Regional Storage and Distribution System Study" (Study) f~r the City of Palo Alto Water Utility. The recently completed Study makes similar improvement recommendations that are urgently necessary to improve the emergency water supply capability of the Palo Alto water distribution system. CMR:141:00 Page 1 of 6 Accelerated Infrastructure Water Main Replacement Program In March 1990 (CMR: 183:0), staff presented a comprehensive view of the infrastructure needs for the water distribution system. In FY 1993/1994, the City Council approved additional funding for an accelerated Water Main Replacement Program which increased the water main replacement rate from 1 to 3 miles a year for water mains. That Council action lowered the rate at which the water distribution mains would be replaced from a 200-year cycle to a more reasonable 75-year cycle. The 75-year cycle is more in line with the useful design life of the materials used to construct the City’s water system. The accelerated program was targeted to replace the deteriorated 4-inch cast iron mains, then focus on 6-inch cast iron mains. To date, the Water Utility has replaced nearly 20 miles of the most deteriorated 4-inch cast iron mains. There are still 4 inch cast iron mains remaining in the water distrbution system that need to be abandoned and or/replaced. The Water Utility is currently in the seventh year of constructing these accelerated water main replacement projects. The attached map (Exhibit A) of the water distribution system shows the water main breaks which have occurred on City distribution mains since approximately 1970, except for main breaks which occurred on mains that have since been replaced. A graph showing the number of water main breaks per year for each type of main material used on the system is also attached (Exhibit B). The City’s water main break rate continues to fluctuate and will only increase as the cast iron mains in the system continue to age and deteriorate. State Department Of Health Services (DHS) Changes To Storage Requirements In 1997, the DHS required the City to determine whether the City water distribution system has the capacity to supply 8 hours of maximum day demand plus required fire flows in each of the City’s nine pressure zones from sources other than the San Francisco Public Utilities Commission Hetch Hetchy pipelines. Only City wells and storage reservoirs were used to analyze the City system’s ability to maintain distribution system pressures, and to quantify the duration for which the maximum day demands and fire flows could be met. The City reservoirs have three distinct purposes: supplying fire fighting demands, supplying emergency demands, and meeting peak daily demands. The analysis of the City’s system showed that storage and emergency supply for the lower elevations of the City distribution system are deficient to meet the DHS-recommended 8- hour period. Furthermore, since the maximum day demands for these areas can not be met during a shutdown of the SF.PUC Hetch Hetchy system, the maximum needed fire flow for this area can not be meet either. The DHS recommendation is reasonable and is on the low end of criteria typically used by other water agencies. If Palo Alto met the minimum DHS requirement, Palo Alto would store 33 percent of its maximum day demand, while other agencies typically store 50 percent to 100 percent of their maximum daily demand. In the future, the current DHS recommendation for emergency storage may become a requirement for water utilities. CMR: 141:00 Page 2 of 6 DISCUSSION The Carollo Engineers Study improvements recommended in the proposed FY 2000/2005 Capital Improvement Program are for: SFPUC chloramine conversion; improvements to normal operations; and capital improvements necessary for the City to supply water during an 8-hour emergency without any external water supply source. In early 2003, the SFPUC will change the disinfectant used in the San Francisco Hetch Hetchy water supply from chlorine to chloramine. When this occurs, the City will not be able to keep water in its reservoirs or distribution system for more than 20 days from the time the water enters the Palo Alto system. If the chloraminated water is not used up by Palo Alto water system demand within 20 days of receiving the water from the SFPUC, water quality problems are very likely to occur in the distribution system. Nitrogen eating bacteria could begin to grow in stored water reservoirs and in rusty cast iron water mains. This operational change by the SFPUC will require the Water Utility to pump and move stored water in and out of foothill reservoirs at a much quicker rate than has be done in the past. The Study recommendations for foothill pump and control valve improvements are necessary to fully optimize the operational efficiency of the foothill storage reservoirs and maintain system water quality. The main focus of the Carollo Study was to consider the consequences to the City’s water service levels during an emergency. Palo Alto is facing two major problems, long-term water supply needs and the existing emergency water supply. The City’s current water system does not meet the minimum DHS emergency water supply recommendation for supplying emergency water (reservoir water or well water) during an 8-hour period without normal system supply (Hetch Hetchy) under maximum day conditions with a fire demand in each pressure zone. The system improvements recommended in the Carollo Study will help the City meet its water demand during an emergency, as defined by the DHS, and for emergency periods longer than 8 hours. The well improvements recommended can be used as long term supply if the well water is treated and meets State water standards. The recommendations of the Carollo Study were developed into five different capital program scenarios. Each of the scenarios includes all the projects recommended in the Study with some timing adjustments made to the water main replacement program. Scenario 1 (Staff Recommendation) The Utilities Department’s recommendation (Exhibit C) is to design and construct all improvements from FY 2000-01 to 2004-05 with the exception of the Mayfield Reservoir Pump Station work being completed in FY 2005-06. This scenario also continues the water main replacement program currently approved by Council. The removal and replacement of the 4-inch cast iron mains is necessary to prevent water quality problems in the distribution system when the Hetch Hetchy supply is converted to chloramine. CMR: 141:00 Page 3 of 6 The rationale for choosing this alternative is because of rates. SFPUC has released its Facilities Reliability Program Phase II - Regional System Overview Executive Summary. The proposed improvements on the SFPUC Hetch Hetchy System are not anticipated to affect the wholesale water rates to the City of Palo Alto until FY 2003-04 at the earliest. The City of Palo Alto’s rate projections contained in Exhibit H include a midpoint of the City projected costs due to the SFPUC capital projects. The 10 year projected effect on the customer water rates for this scenario is shown in Exhibit H, "Impact of CIP Scenarios on an Average Customer’s Bill in Dollars." Scenario 1, Exhibit C, gives the City Water Utility the best opportunity to install the Carollo Study recommendations to improve the overall emergency reliability and service level of the Palo Alto water system before future SFPUC water supply costs are included in Palo Alto’s water rates. Exhibits D through G show alternative scenarios two through five. Scenario 2 Exhibit D includes constructing all of the Study recommendations within a five-year period with the exception of the Mayfield Reservoir Pump Station work, which will be completed in FY 2005-06, but modifies the main replacement program. In this scenario, however, only the design work is completed on Water Main Replacement Projects 15-19, with the construction deferred until FY 2006-07 to FY 2009-10 respectively. The City would design and construct Water Main Replacement Projects 20, 21, 22, 23, and 24 during F¥2006-07 to FY2009-10. This proposal defers construction of planned water main projects from the second through fifth fiscal years but doubles the construction effort in the last four fiscal years of the ten-year period. The 10-year projected effect on the customer water rates for this scenario is shown in Exhibit H. Scenario 3 Exhibit E is the third scenario, which includes constructing all the Study recommendations within, the first five years with the exception of the Mayfield Reservoir Pump Station work being completed in F¥ 2005-06. Scenario 3 defers the design and construction of Water Main Replacement Projects 15, 16, 17, and 18 until FY 2005-06 through F¥ 2009-10. This proposal would also double the City’s main replacement rates through F¥ 2005-06 to F¥ 2009-10 from the current three miles per year to six miles of water main replacements per year. The 10-year projected effect on the customer water rates for this scenario is shown in Exhibit H. Scenario 4 Scenario 4 (Exhibit F) includes all of the recommended improvements being designed and constructed during the first 5 years of the program with the Mayfield Reservoir Pump Station work being constructed in F.Y 2005-06. Scenario 4 proposes a modification to the water main replacement program that reduces the program from 3 miles to 1.5 miles of water main replacements in F¥ 2001-02 to F¥ 2004-05. The 1.5 miles of mains that are deferred from these fiscal years would be designed and constructed in FY 2005-06 CMR: 141:00 Page 4 of 6 through FY 2009-10. This proposa! would increase the water main replacement level to 4 .5 miles in FY 2006-07 to FY 2009-10. The 10-year projected effect on the customer water rates for this scenario is shown in Exhibit H. Scenario 5 Scenario 5 (Exhibit G) spaces the design and construction of the improvements over the entire 10-year period. The improvements for the normal distribution system operation and the chloramine conversion projects are started in FY 2000-01. Design of most of the. emergency 8-hour improvements is started in FY 2003-04. The construction of these improvements is spaced out through F¥ 2005-06 through FY 2009-10. The 10-year projected effect on the customer water rates for this scenario is shown in Exhibit H. RESOURCE IMPACT The CIP recommended in Scenario 1 will add approximately $15.7 million dollars to Water Capital Improvement program during FY 2000-05 (1999 dollars). The financial impacts on the Water Fund are shown on the attached Exhibits C through G. The rate variance on the average residential water customer’s monthly bill for each of these Exhibits is in Exhibit H. For all of the scenarios (1-5) presented and the rate impacts in Exhibit H staff has assumed the proposed CIP would be paid directly from water rate revenues. Exhibit C is also shown in Exhibit H with an option for bond financing. Exhibit D through G as shown on Exhibit H, assume that the proposed CIP, as it has been the practice in the past, will be paid for through rates. Exhibit C assumes bond financing as an option to fund the proposed water CIP. Presently, staff is evaluating the option of bond financing. EXHIBITS Exhibit A: Map of Water Main Breaks Since 1970 Exhibit B: Chart of Water Mains Breaks by TypeofPipe, 1997 to 1999 Exhibit C: 10Year Projection FY 2000-2010 with 5-Year Consultant Recommended Work - WMR Program remains as Council Approved Exhibit D: 10Year Projection FY 2000-2010 with 5-Year Consultant Recommended Work - Years 1-5 WMR Design Work Only; Years 6-10 double construction Exhibit E: 10Year Projection FY 2000-2010 with 5-Year Consultant Recommended Work - Years 2-5 No WMR Work; Years 6-10 double WMR Program Exhibit F: 10Year Projection FY 2000-2010 with 5-Year Consultant Recommended Work - Years 2-5 HalfWMR Program; Years 6-10 One and 1/2 WMR Program Exhibit G: 10Year Projection FY 2000-2010 with 10-Year Consultant Recommended Work - WMR Program remains as Council Approved CMR: 141:00 Page 5 of 6 Exhibit H: Impact of CIP Scenarios On the Average Customer’s Bill In Dollars PREPARED BY: Roger Cwiak, Manager, W/G/W Engineering DEPARTMENT HEAD APPROVAL: CITY MANAGER APPROVAL: ,~irect°~ilities CMR: 141:00 Page 6 of 6 LEGEND: ~ATER, MAIN BREAKS~ 2000) LU W° 01/24/2000, 04"50 PM EXHIBIT C 2000-2010 CAPITAL IMPROVEMENT PROJECTS WATER FUND (10 - Year Projection, with 5 year compressed consultant recommended work) W~ATER FUND Distribution ~System - Customer Design and Connection ~ervices Water System Extensions (8013) "ull Relmbursment by Customer Yet Subtotal Distibution System - Customer Design and $02onnectlon Se~ices Distribution System - System Improvements $334,000 $320,000 $287,000 $296,~0 $305,000 $314,000 $323,000 $332,000 $341,000 $350,000 $3,202,000 ~33~000)($320,000)($28~000)($296,000)($305,000)($314,000)($323,000)($332,000)($341,000)($35~000)($3,202,000) $0 $0 $0 $0 $0 $0 $0 SO $0 $0 Water Main Replacements Phase 14 $2,327,000 N $1,821,000 $1,821,000 Water Main Replacements Phase 15 (0106)N -$192,000 $t,867,000 $2,059,000 Water Main Replacements Phase 16 (0203)St96,500 $1,913,200 $2,109,700 Water Main Replacements Phase 17 (0304)$201,500 $1,960~000 $2,161,500 Water Main Replacements Phase 18 (0401)$206,400 $2,010,000 $2,216,400 Service and Hydrant Replacement (8014)S75~000 $77~000 $80,000 $82~500 $85,500 $88,500 $91,500 $94,500 $97,500 $100,500 $872,500 Water Meters (8015)$190,0~0 $195,0~0 $200~000 $206,000 $213,000 $220,000 $227,000 $234,0~0 $241,000 $248,000 $2,174,660 $5,400,950 $5,873,500 $3,876,700 $11,059,900 $2,520,500 $3,825,500 $2,650,500 $2,726,500 $2~793,500 $2,868~00 $43~596,050Net Subtotal Distribution System - System Improvements I’OTAL NET WATER DISTRIBUTION FUND REQUESTS $5,400,950 $5,873,500 $3,876,700 ~11,059,900 $2,520,500 $3,825,500 $2,650,500 $2,726,500 $2,793,500 $2,868,500 $43,596,050 BUDGETS 295~ COST DIFFERENCE FROM PREVIOUS YEAR $2,436,700 $2,983,500 $945,950 58,061,290 n/a n/a n/a n/a n/a n/a ~82.20%103.24%32.28%268.83%nla n/a n/a n/a n/a n/a N= Normal and Fire Suppression Demand C = Chloramine Improvements 8 = 8 hour DHS storage recommendation Water Quality Enhancement costs EXCLUDE $200,000 reservoir cleaning - NON CIP; an operations function OABORG\CIPWTR6E.WK4 0112412000, 05:07 PM EXHIBIT D 2000-2010 CAPITAL IMPROVEMENT PROJECTS ¯ WATER FUND (10 - Year Projection, with 5 year compressed consultant recommended work) YEARS l-5 WMR DESIGN WORK ONLY; YEARS 6-10, CONSTRUCTION WATER FUND Distribution System - Customer Design and Connection Services Water Sysiem Extensions (8013) $334,000 $320,000 $287,000 $296~000 $305,000 $314,000 $323,000 $332,000 $341,000 $350,000 $3,202,000 Full Reimburstnent by Customer ($334,000)($320,000)($287,000)($296,000)($305,000)($314~000)($323,000)($332,000)($34I~000)($350,000)($3,202,000) Net Subtotal Distibutilm System - Customer Design and $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Connection Selwices $68,750 Water Main Replacements Phsse 14 (14)N $1,821,1 $1,821,1 Water Main Replacemen~ Phase 15 (0106)N $192,~$I,867,~$2,059~ Water Main Replacem~ts Phase I6 (0203)$196,5~$l,913,2~ Water Msln Replacements Phase 18 (~01)$2~,4~$2,010,~$2,216,4~ ¯ OTAL NET WATER DISTRIBUTION FUND REQUESTS $5,400,950 $4,006,500 $L963,5~$9,099,900 $510,500 $3,825,500 $4,517,500 $4,639,700 $4,753,500 $4,878,500 $43,596,050 COST DIFFERENCE FROM PREVIOUS YEAR $2,436,700 $1,116,500 ($967,250)$6,101,290 n/s n/a n/a n/a n/a rda ~z~F.~~82.20%38.63%-33.00%203.47%n/a n/a n/a n/a n/a n/a N = Normal and Fire Suppression Demand C = Chloramine Improvements 8 = 8 hour DHS storage recommendation Water Quality Enhancement costs EXCLUDE $200,000 reservoir cleaning - NON CIP; an operations function O:~B OR.G\CIPWTR6F.WK4 01/24/2000, 05:10 PM EXHIBIT E 2000-2010 CAPITAL IMPROVEMENT PROJECTS WATER FUND (10 - Year Projection, with 5 year compressed consultant recommended work) YEARS 2-5 WMR NO WORK; YEARS 6-10, DESIGN & CONSTRUCTION NATER FUND [~istribution ~iystem - Customer Design and Connectionervkes Water System Extensions (8013) $334,000 $320,000 $287,000 $296,000 $305,000 -$314,000 $323,000 $332,000 $341,000 $350,000 $3~202,000 FullRelmbursmentbyCustomer ($334,000)(5320,000)(~287,000)($296,000)($305,000) ($314,000)($323,000)($332,000)($341,000)($350,000)($3,202,000) Net Subtotal Disfbution System - Customer Design and $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 ~onnection Services Distribution System - System Improvements Water Main Replacements Phase 14 (0004) Water Maln Replacements Phase 15 (0106)S192,000 $1,867,000 $2,059,000 Water Main Replacements Phase 16 (0203) Water Main Replacements Phase 17 (0304) Water Main Replacements Phase 18 (0401) Service and Hydrant Replacement (8014) Water Meters (8015) Net Subtotal Distribution System - System Improvements TOTAL NET WATER DISTRIB UTION FUND REQUESTS $396,500 SI,913,200 S2,109,700 $206,400 $2,010,000 $2,216,400 $75,000 $77,1~0 $80,0~0 $82,500 $85,500 $88,500 $91,500 $94~500 $97,500 $100,500 $872,500 $190,000 SI95,000 $200,0~O $206,000 $213,000 $320,000 S227,000 $234,000 $241,000 S248,000 $2,174,000 S5,208,950 $3,810,0~}$1,762,000 $8,893,500 $510,500 $4,017,500 $4,714,000 $4,841,200 $4,959,900 $4,878,500 $43,596,050 $5,208,950 $3,810,000 $1,762,000 $8,893,500 $510,500 $4,017,500 $4,714,000 $4,84t,200 $4,959,900 $4,878,500 $43,596,050 BUDGETS COST DIFFERENCE FROM PREVIOUS YEAR $2,244,700 $920,0~0 ($1,168,750) $3,894,890 n/a n/a n/a ~n/a nla n/a 75.73%31.83%-39.88%196.59%n/a nla n/a - n/a nla N = Normal and Fire Suppression Demand C = Chloramine Improvements 8 = 8 hour DblS storage recommendation Water Quality Enhancement costs EXCLU_DE $200,000 reservoir cleaning - NON CIP; an operations function OABORG\CIPWTR6G.WK4 01/24/2000, 05:12 PM EXHIBIT F 2000-2010 CAPITAL IMPROVEMENT PROJECTS WATER FUND (10 - Year Projection, with 5 year compressed consultant recommended work) YEARS 2-S WMR 1/2 DESIGN AND CONSTRUCTION WORK; YEARS 6"-10, DESIGN & CONSTRUCTION VATERFUND D]stribution System - Customer Design and Connectioniet-vlces ~Vater System Extensions (8013) ~ull Relmbursmenl by Customer let Subtotal Distibution System - Customer Design and $0Connection Services Distribution System - System Improvements $334,000 $320,000 $287~000 $296,000 $305,000 $314,000 $323,000 $332,000 $341,000 $350,000 $3,202,000 ($334,000)($320,000)($287,000)($296,000)($305,000)($314,000)($323,000)($332,000)($341,000)($350,000)($3,202,000) $0 $0 $0 $9 $0 $o $o $o $0 $o Nater Main Replacements Phase 15 (0106)i N $96,000 $933,500 !Water Main Replacements Phase 16 (0203) Water Main Eeplacement~ Phase 17 (0304) Water Main Replacements Phase 18 (0401) Service and Hydrant Replacement (8014) $96,000 $933,500 $2,059,000 $98,250 $956,600 $98,250 $956,600 $2,109,700 $100,750 $980,0~0 S100,750 $980,000 $2,161,500 $103,200 $1,0~5,000 $103,200 $t,005,000 $2,216,400 $75,000 $77,0~0 $80,000 $82,500 $85,500 $88,500 $91,500 $94,500 $97,500 $100~500 $872,560 $190,000 $195,000 $200,000 $206,000 $213,000 $220,000 $227,000 $234~000 $241,000 8248,000 $2,174,000 $5,304,950 $4,841,750 $2,819,350 $9,976,700 $1,SI5,500 $3,921,500 $3,682,250 $3,783,850 $3,876,700 $3,873,500 $43,596,050 $5,304,950 $4,841,750 $2,819,350 $9,976,700 $1,515,500 $3,921,500 $3,682,250 $3,783,850 $3,876,700 $3,873,500 $43,596,050 Water Meters {8015) Net Subtotal Distribullon System - System Improvements TOTAL NET WATER DISTRIBUTION FUND REQUESTS BUDGETS COST DIFFERENCE FROM PREVIOUS YEAR $2,340,700 $l,951,750 ($111,400)$6,978,090 n/a n/a n/a n/a n/a n/a ?8.96%67.53%-3.80%232,71%n/a n/a n/a n/a n/a n/a N = Normal and Fire Suppression Demand C = Chloramine hnprovelnents 8 = 8 hour DHS storage recommendation Water Quality Enhancement costs EXCLUDE $200,000 reservoir cleaning - NON CIP; an operations function O.~ORG\CIPWTR6H.WK4 01/24!2000, 05:t6 PM EXHIBIT G 2000-2010 CAPITAL IMPROVEMENT PROJECTS WATER FUND (10 -Year Projection) WATER FUND Services i~/ater System Extensions (8013) $334,000 $320,000 $287,000 $296,000 $305~000 $314,000 $323,000 $332,000 $341,000 $350,000 $3,202,000 FidlRelmburstnent by Customer ($334,000)($320,000)($287,000)($296,000)($305,000)($314,000)($323,000)($332,000)($341,000)($350,000)($3,202,000) Net Subtotal Distibutlon System - Customer Design and $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 Distribution System- System Imp ...... ts . I [’ L;/!l~l:l~i!d~j IID;+=~r~lli~n,,... ,- .~,,:.~ ....I’iI’~ ’I.~.,~.,~<=>_~<<. ’~l;i:~:~<i Wil llii’;:::~’~ IliI::Iel ~I~i I ~it,i~l~.~l,i~,, ...:;~<~=~" Water Main Replacement~ Phase 14 (~)N $1,821,~$1,821,~ Water Main R~latem~ Phase 15 (0106)N $t92,~$1,867,~$2~059,~ Water Main Replacemen~ Phase 16 (0203)$196,5~$1,913,2~$2,1~,7~ Water Main Replacemen~ Phase 17 (0304)$201,5~$1,960,~$2,161,5~ Water Main Replacements Phase 18 (0401)$2~,4~ Net Subtotal Distribution System - System Improvements $3,725,950 $3,674,~ ~3,134,7~ $7,756,9~ $2,520,5~ ~,905,5~ $7,545,5~ $2,883,5~ $4,143,~ ~,368,5~ $44,659,050 ¯ OT~ NET WATER DISTRIBUTION FUND REQUESTS ~,725~950 $3,674,500 $3,134,700 $7,756,900 $2,520,500 $4,905,500 $7,545,5~$2,883,500 $4,143,500 $4,368,500 $44~659,050 ¯ *25.70%27.15%6.96%158.68%n/a ~a n/a n/a ’n/a n/a N = Normal and Fire Suppression Demand C = Chloraraine Improvements 8 = 8 hour DHS storage recommendation Water Quality Enhancement costs EXCLUDE $200,000 reservoir cleaning - NON CIP; an operations function O.~ORG\CIPWTR6[.WK4 "i- o>¯ i-o