Bowen Island Municipality

Transcription

1 Bowen Island Municipality Hood Point Water System EOCP Small Water System # Drinking Water Quality Annual Report Calendar Year March 30, 2016

2 TABLE OF CONTENTS EXECUTIVE SUMMARY... 3 A. INTRODUCTION... 3 B. ADMINISTRATION... 3 BIM Staff... 4 Hood Point Water System Local Advisory Committee... 4 C. SYSTEM DESCRIPTION... 4 General... 4 Water Supply and Storage... 4 Treatment... 5 Water System... 5 D. WATER QUALTIY... 6 Water Quality Testing... 6 Results... 7 E. EVENTS, GRANTS, STUDIES AND REPORTS, SYSTEM IMPROVEMENTS... 8 Events... 9 Grants, Studies, and Reports... 9 System Improvements in Future Planning for F. ADVISORIES... 9 Water Main Flushing Advisories... 9 Drinking Water and Persons Who Are Immunocompromised Advisories... 9 G. OPERATOR TRAINING/QUALIFICATIONS H. SECURITY MEASURES I. EMERGENCY RESPONSE PLANS APPENDIX 1 SYSTEM MAP APPENDIX 2 WATER QUALITY APPENDIX 3 ALS ENHANCED WATER POTABILITY ANALYSIS APPENDIX 4 NOTIFICATION AND EMERGENCY RESPONSE APPENDIX 5 VCH WATERMAIN BREAK RESPONSE FOR DWO S APPENDIX 6 MUNICIPAL UTILITY OPERATORS CERTIFICATION APPENDIX 7 PERMIT TO OPERATE Page 2 of 31

3 EXECUTIVE SUMMARY This report has been prepared to support an application for an annual Ministry of Health Operating Permit issued by the Medical Health Officer as required by the Drinking Water Protection Act and Regulation. Since its incorporation in December of 1999, Bowen Island Municipality (BIM) has undergone many changes. Those directly affecting water system operation include the changes to the internal staffing structure, the operating strategy and operations contracting, all occurring late in These changes have begun to result in more consistent and accountable water quality reporting and infrastructure upgrade planning. The year 2004 was the first full calendar year with Municipal Staff responsible for Hood Point Water System operation and maintenance. In May of 2010, Bowen Island Municipality brought all maintenance and operations of the six municipal water systems in-house. There were no boil water advisories issued for Hood Point Water System in A. INTRODUCTION Hood Point Water System is one of seven water systems owned and operated by BIM. Water is supplied from a surface water source to approximately 101 residential connections in the Hood Point area. The Water System consists of one pressure zone, and all service connections are metered. Meters are read regularly, however meterbased billing is not in effect. Issues which challenge the System include the following: source water protection; treatment; fire protection; operational limitations; potential for water main freezing during winter. B. ADMINISTRATION The operation and management of Hood Point Water System is administered by BIM, with assistance from other organizations. For its water system operation and management, BIM relies on BIM staff and the Hood Point Water System Local Advisory Committee. Page 3 of 31

4 BIM Staff The Public Works Superintendent oversees the water system operations, interacts with internal staff on operational and maintenance issues on a daily basis, coordinates the supply and delivery of parts and supplies, and coordinates with engineering consultants. The ultimate responsibility for water system operation and maintenance lies with Bowen Island Municipality. Hood Point Water System Local Advisory Committee The Hood Point Water System Local Advisory Committee is a sub-committee of Municipal Council. It has advisory powers to Council regarding water system issues, and also reviews the operating and capital budgets for the utility. The Committee was established prior to Municipal incorporation, when the System was administered as an Improvement District. C. SYSTEM DESCRIPTION General Hood Point Water System is one of seven separate water systems owned and operated by Bowen Island Municipality. The System is located on the east side of Bowen Island and is set in a rural area amongst nature, abundant vegetation and surrounding forest. Funding through user fees, it is not subsidized by General Municipal or other funds. Hood Point Water System was originally constructed and operated as an Improvement District. Hood Point Water System has been classified by the EOCP as being a Small Water System (System number 656). The Ministry of Health Planning has issued a Permit to Operate as Facility Number Water Supply and Storage The source of water for Hood Point is from Honeymoon Lake located approximately 2.7 km to the west of Hood Point. The Municipality has over 120 separate water licenses on Honeymoon Lake and Creek for this water system. When the Water System was originally set up, each property had its own water license and these have not been combined to reduce the cost of the licensing. The total catchment area of the lake is km 2. The existing useable storage volume of the lake is approximately 71,000 m 3 based on a depth of 2.49 m of storage below the Page 4 of 31

5 crest of the spillway. A 30 m wide earth fill dam is located to the west of the lake. A concrete spillway controls the top water level of the lake. The reported spillway level at the lake is elevation ±172.5 meters. The lake intake consists of a 70 m long 200 mm Ø DR 32.5 HDPE pipe with a stainless steel well screen supported by a floating wooden raft. The screen provides coarse filtering of the water as it enters the supply main. The supply main consists of approximately 1525 mm of 150 mm Ø DR 35 HDPE and 1660 m of 100 mm Ø DR 21 to DR 9 pipes from the west side of Honeymoon Lake. Most of the HDPE supply main is located above ground and is subject to freezing during the winter. Treated water is stored in a 50,000 IGal concrete tank, located south of Hood Point. The top water level (TWL) of the tank is at elevation 96.5 meters. Treatment The water from the supply main is treated in a filtration and disinfection facility before storage in the tank. Water treatment consists of rapid sand filtration, UV disinfection and chlorination. The water is filtered through two USF AMM36-2F7D-CC multimedia filters. The filter tanks are fiberglass with a rated 225 l/sec (50 Igpm) capacity at a maximum system pressure of 100 psi. The media bed consists of anthracite, filter sand and garnet on a graded quartz support bed. The multimedia filters are rated for removal to 10 microns. A pressurized UV light system is installed after the filters, and before the chlorination system. Water treatment is by flow-paced injection of sodium hypochlorite into the water supply main with limited contact time and is UV disinfected. Turbidity is recorded by the SCADA system and monitored regularly by BIM Utility Operators. The treated water goes to the 50,000 gallon storage reservoir. Water System The Hood Point Water System consists of one pressure zone which is controlled by the top water level in the reservoir. The Hood Point Water System consists of: Approximately the following lengths of DR 13.5 and DR 11 HDPE pipe: m of 250 mm Ø pipe m of 200 mm Ø pipe Page 5 of 31

6 m of 150 mm Ø pipe m of 100 mm Ø pipe m of 50 mm Ø pipe 10 fire hydrants 101 service connections 115 service connections (including vacant lots) D. WATER QUALITY BIM is responsible for ensuring raw and treated water quality is monitored and tested as follows: Treated water quality samples: - Daily manual testing is performed for chlorine, - Weekly water samples are directly relayed to Vancouver Coastal Health Authority (North Shore) for Total and Fecal Coliform testing, - Annual THM and HAA testing. Raw water quality samples: - Raw water sampling is performed twice a year. Water Quality Testing BIM s sampling program is based on accepted protocols developed in consultation with the Medical Health Officer. The program provides bacteriological, chemical and physical testing to evaluate water quality. There are three sampling stations located within the System to give an indication of the water quality throughout the Water System, plus one sampling station at the treatment building for turbidity. Test locations within the Hood Point Water System are as follows: Site Approximate Address Tested For No. No Hood Point Road Chlorine Residuals No Eagle Cliff Road No. 3 Hood Point Water Treatment Plant Chlorine Residuals/Turbidity Maximum acceptable concentrations have been established for certain substances known or suspected to cause adverse effects on health. The standards have been derived to safeguard health on the basis of lifelong consumption and the use of the water for all usual domestic purposes, including personal hygiene. A description of all test parameters, allowable limits and a summary of the 2015 test results may be viewed in the Water Quality section of the Appendices. Page 6 of 31

7 Results a. Bacteria There were no boil water advisories issued for Hood Point Water System in b. Physical Water temperature and turbidity are beyond the control of Hood Point Water System. Of the 364 Turbidity readings taken, 80 (22%) read above 1NTU. c. Chemical As of April 2005, the operators began maintaining 0.2 ppm as a minimum target level. Sampling stations indicate that the recommended minimum chlorine residual was generally maintained during The historical trend for chlorine residual statistics is as follows: Location Hood Point Road Year No. of Readings High (ppm) Low (ppm) Average (ppm) Location Treatment Plant Year No. of Readings High (ppm) Low (ppm) Average (ppm) Page 7 of 31

8 Location Eagle Cliff Road Year No. of Readings High Low Average The turbidity results for 2015 are as follows: Turbidity (NTUs) Year No. of Readings High (NTU) Low (NTU) Average (NTU) d. THMs and HAAs The following analytical results are from the Hood Point Water System for: disinfection by-products (Haloacetic Acids and Trihalomethanes). This monitoring is required under the Water Quality Monitoring and Reporting Plan for Metro Vancouver and Member Municipalities. THM and HAA test results are provided in Appendix 3, and summarized as follows: Year Date Location 15-Jul Eaglecliff Rd 17- Dec Eaglecliff Rd 08- Jul Hood Point Rd Eaglecliff Rd 13-Jan 10-June 05-Jan Hood Point Rd Eaglecliff Rd Treatment Plant Eaglecliff Rd Hood Point Rd Recommended Maximum THMs ppb HAAs ppb* E. EVENTS, GRANTS, STUDIES AND REPORTS, SYSTEM IMPROVEMENTS The following events were noted regarding Hood Point Water System in 2015: Page 8 of 31

9 Events There were no significant events in Grants, Studies and Reports Bowen Island Municipality will continue to update its website to include information about the Water System as any future grants, studies or reports are completed. System Improvements in 2015: Dam Safety Emergency plan for Honeymoon Lake Dam. O&M manual was produced and implemented. Re and Re PRV ongoing UV upgrade, ongoing Honeymoon access road was upgraded. Honeymoon Lake dam upgraded Fire hydrant tear down and service Future Planning for 2016: UV and isolation valve upgrade Air valve covers replace and repair on supply line. 50,000 Gal concreate reservoir cleaning. Extension of water intake in Honeymoon Lake F. ADVISORIES Water Main Flushing Advisories Public advisories were issued by the Municipality prior to water main flushing which is completed twice each year. An advisory was issued for the following periods: March 9 April 17, 2015 October 3 November 13, 2015 Drinking Water and Persons Who Are Immunocompromised Advisories Water advisories were published quarterly advising water users with compromised immune systems to ensure their drinking water is boiled, filtered or distilled. Advisories were issued for the following periods: January 1, 2015 April 3, 2015 Page 9 of 31

10 July 3, 2015 October 2, 2015 G. OPERATOR TRAINING/QUALIFICATIONS The following table summarizes the qualifications of BIM staff for the 2015 calendar year. Employee Position Courses/Qualifications Work Experience Bob Robinson Duy Son Tom Woodward Public Works Superintendent Bowen Island, BC October 2003-present Utility Foreman Utility Operator BIM STAFF EOCP Level 1 Water Distribution System Operator EOCP Level 1 Water Distribution System Operator EOCP Small Water System Operator 22 years water main construction experience. 13 years Municipal Public Works experience. 5.5 yrs Municipal Utility experience 3 yrs Municipal Utility experience Midge Meeres Utility Operator EOCP Small Water System Operator 2 yr Municipal Utility experience Doug Woods Utility Operator Water System Operator/In Training.5 yr Municipal Utility experience Geeritt Duntz Utility Operator Water System Operator/In Training.5 yr Municipal Utility experience H. SECURITY MEASURES Security measures for water systems typically concentrate on protection of water sources and reservoirs. BIM has not employed any extraordinary measures. Supply points (dam, main from dam to storage facilities, and treatment plant) could be the most vulnerable components of our system but in reality are no more vulnerable than fire hydrants and individual service connections. BIM will continue to be apprised of security issues and will implement operational changes as required. Page 10 of 31

11 I. EMERGENCY RESPONSE PLANS BIM Notification and Emergency Response Plans as well as Vancouver Coastal Health Watermain Break Response Guidelines for Drinking Water Officers are included in the Appendices. Affected staff has been informed of the plan to prepare for appropriate action at critical moments. Page 11 of 31

12 APPENDIX 1 SYSTEM MAP Page 12 of 31

13 APPENDIX 2 WATER QUALITY The following provides a simple description of the sampling parameters: Sample Parameter Sample Description Fail Limit CL2Free mg/l Free Chlorine in milligrams per litre <.2 The chlorine residual within the Water System is the indicator for the effectiveness of the disinfection process. The goal is to maintain a minimum of 0.2 mg/l at the extremities of the Water System. Fcoli MF/100mLs Fecal coliforms Membrane Filtered per 100 millilitres 0 The microbiological quality of water is measured by sampling the number of coliform organisms. Fecal coliforms are considered key indicators and could indicate sewage contamination. None of the coliform organisms detected should be fecal coliforms. In rare circumstances the fecal coliform test and the total coliform test will read MPN/100mLs. This indicates the sample was too turbid for the normal Membrane Filtration test and required an alternative method. MPN is an abbreviation of Most Probable Number. Tcoli MF/100mLs Total coliforms Membrane filtered per 100 millilitres >10 The microbiological quality of water is measured by sampling the number of coliform organisms. No sample should contain more than 10 total coliforms per 100 millilitres and 90 percent or more of the samples taken in a 30-day period must have zero coliform organisms. As well, no more than 2 consecutive samples from the same site should show the presence of coliform organisms. Turbidity NTU Turbidity nephelometric turbidity unit >1 Turbidity describes the amount of sediment in water. The presence of turbidity can have significant effects on both the microbiological quality of water and on the detection of bacteria and viruses. More important, however, is the sediment interferes with the disinfection process. The interference with chlorination can range from negligible to severe. Page 13 of 31

14 Results The following charts illustrate the Chlorine Residual results at each sampling station and the Turbidity at the Hood Point Water Treatment Plant in Bowen Island Municipality Hood Point Water System - Treatment Plant - Chlorine Residuals (ppm) Bowen Island Municipality Hood Point Water System - Hood Point Rd - Chlorine Residuals (ppm) Page 14 of 31

15 Bowen Island Municipality Hood Point Water System - Eaglecliff Rd - Chlorine Residuals (ppm) 6.00 Bowen Island Municipality Hood Point Water System Hood Point Water Treatment Plant - Turbidity (NTU) Page 15 of 31

16 APPENDIX 3 ALS ENVIRONMENTALENHANCED WATER POTABILITY ANALYSIS Page 16 of 31

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24 APPENDIX 4 - NOTIFICATION AND EMERGENCY RESPONSE Hood Point Water System Bowen Island Municipality Potential Emergency Situations and Responses Broken water main Bowen Island Municipal System Operators will isolate the affected part of the system, shut water off and arrange for repairs Notify the Public Works Manager Notify affected users of interruption in service Post emergency sign, if necessary Advise Bowen Island Fire Department Arrange alternate source if necessary (bottled water) Advise Vancouver Coastal Health Authority (North Shore) Contact affected users and Vancouver Coastal Health Authority (North Shore) when system has been repaired. Chlorinator failure Bowen Island Municipal System Operators will arrange for chlorinator repairs Notify the Public Works Manager Advise Vancouver Coastal Health Authority (North Shore) Notify all users to boil water or take other disinfection procedures in accordance with recommendations of local health officials Issue Boil Water Advisory to all users Post emergency sign, if necessary Contact users and the System Operator when Boil Advisory has been rescinded Pump failure Bowen Island Municipal System Operators will arrange for repairs Notify the Public Works Manager Notify users in the affected area of interruption in service Post emergency sign if necessary Arrange alternate source if necessary (bottled water/bulk hauler/storage tank) Advise Vancouver Coastal Health Authority (North Shore) Contact users and Vancouver Coastal Health Authority (North Shore) when pump has been repaired Power failure Bowen Island Municipal System Operators to transport generator to site, connect to system and power-up. Bowen Island Municipal System Operators to arrange with BC Hydro for repairs if necessary Notify Public Works Manager Notify BC Hydro Post emergency sign, if necessary Notify affected users of interruption in service if the power shortage is going to be long enough that storage tank will run dry Arrange alternate source if necessary (bottled water/bulk hauler/storage tank) Contact Vancouver Coastal Health Authority to inform them of what happened. Contamination of/or loss of source (e.g. Bowen Island Municipal System Operators will put up emergency sign, if necessary, and shut down system Page 24 of 31

25 spills, vandalism) Advise Public Works Manager Advise Vancouver Coastal Health Authority (North Shore) Prepare notice weekdays distribute notice via mail, weekends hand deliver or distribute the most efficient way possible Contact government agencies for advice and assistance (e.g., Provincial Emergency Preparedness, RCMP, Ministry of Environment, Department of Fisheries) Advise Media outlets Arrange alternate source if necessary (bottled water/bulk hauler/storage tank) Contact users and Vancouver Coastal Health Authority (North Shore) when problem has been resolved Abnormal or suspect water quality result detected by System Operator Coliform count too high from samples Backflow or back siphonage Natural Disasters such as fire, flooding, earthquake, mudslide, dam failure. Advise Vancouver Coastal Health Authority (North Shore) immediately, and follow their directives. If users have to be notified, follow same procedure as when coliform count is too high from samples Bowen Island Municipal System Operators to initiate remedial measures as directed by Vancouver Coastal Health Authority (North Shore) Contact Public Works Manager Notify all users to boil water or take other disinfection procedures in accordance with recommendation of local health officials Post emergency sign if necessary Issue Boil Advisory to all users Contact users when Boil Advisory has been rescinded Bowen Island Municipal System Operators to isolate affected part of the system, arrange for repairs/corrections, and purge and disinfect lines as necessary after repairs/corrections have been made Advise Public Works Manager Advise Vancouver Coastal Health Authority (North Shore) Post emergency sign if necessary Contact affected users to boil water or take other disinfection procedures in accordance with recommendation of local health officials Issue Boil Advisory to affected users with the recommendations of the Local Health Officials Contact affected users when Boil Advisory has been rescinded Notify Bowen Island Fire Department Advise Public Works Manager. Advise Vancouver Coastal Health Authority (North Shore) Contact all users Contact government agencies for advice and assistance (e.g., Provincial Emergency Preparedness, RCMP, Ministry of Environment, Department of Fisheries) Arrange alternate source if necessary (bottled water/bulk hauler/storage tank) Contact users and Vancouver Coastal Health Authority (North Shore) when system has been repaired Notification It is intended to notify the Public Works Manager, Bowen Island Fire Department, Vancouver Coastal Health Authority (North Shore), B.C. Hydro and various government agencies by phone, or fax. It is intended to notify the System Users by the following methods, as Page 25 of 31

26 required: Phone Post emergency signage Written Notice distributed by mail Written Notice distributed door to door Written Notice posted in strategic locations Written notice in newspaper/local media Verbally by going door to door Public Notice through radio or television Other means as determined by severity of emergency Page 26 of 31

27 APPENDIX 5 VANCOUVER COASTAL HEALTH WATERMAIN BREAK RESPONSE GUIDELINES FOR DRINKING WATER OFFICERS Type 1 Break Type 2 Break Type 3 Break Controlled pipe repair Controlled pipe repair Uncontrolled pipe repair Positive pressure maintained during break Positive pressure maintained during break Loss of pressure at break site/possible local depressurization adjacent to the Pressure maintained during repair (full shutdown is not needed) No signs of contamination intrusion Pressure maintained until controlled shutdown (shutdown after the repair site is secured against soil/water contamination) No signs of contamination intrusion break (<20 psi) Partial or uncontrolled shutdown Possible contamination intrusion (muddy water entering the pipe or leaking sewer pipe in the trench) Procedure Procedure Procedure Notify the DWO if necessary, see Note 1 Notify the DWO if necessary, see Note 1 Notify the DWO if necessary, see Note 1 Excavate to below break Excavate to below break Excavate to below break Maintain trench water level below break Maintain trench water level below break Maintain trench water level below break Repair under pressure Controlled shutdown for repair Uncontrolled shutdown for repair Isolate section of pipe in which the break is located with all service connections shut off Clean and disinfect repair site by spraying or swabbing with minimum 1% chlorine solution Disinfect repair parts by spraying or swabbing with minimum 1% chlorine solution Flush to obtain three volumes of water turnover (and until flushed water is visually clear) Check residual chlorine level until typical levels are restored Clean and disinfect repair site by spraying or swabbing with minimum 1% chlorine solution Disinfect repair parts by spraying or swabbing with minimum 1% chlorine solution Scour flush (at 3 ft/s) to obtain three volumes of water turnover (and until flushed water is visually clear) Check residual chlorine level until typical levels are restored Page 27 of 31 Clean and disinfect repair site by spraying or swabbing with minimum 1% chlorine solution Disinfect repair parts by spraying or swabbing with minimum 1% chlorine solution Scour flush (at 3 ft/s) to obtain three volumes of water turnover (and until flushed water is visually clear) Follow disinfection procedures for new pipe installation, if possible. Alternatively, keep chlorine residual of 4 mg/l for at least 16 hours or 300 mg/l for 15 minutes, then flush Check residual chlorine level until typical levels are restored Check with bacteriological testing (DWO to decide if service may be restored before results), see Note 2

28 Return watermain to service Return watermain to service Return watermain to service No bacteriological samples Check with bacteriological testing (no need to wait for results), see Note 2 Instruct customers to flush premise plumbing upon return to service No BWN No BWN BWN if area of depressurization is larger than the treated area Notes: Note 1 Notification A) Notify the Drinking Water Officer during normal operation hours if: customers are out of water or experience extreme drop in water pressure, there is widespread loss of residual chlorine in the water system, there is media attention, there is a potential risk of contamination, or there is disruption of service to high risk facilities (such as health care facilities), or a significant portion of residential or commercial users in the community are affected. the watermain might have been contaminated and cannot be disinfected the watermain cannot be adequately flushed after disinfection bacteriological results are unsatisfactory B) Notify the Manager-on-call outside operation hours if: (Health Protection 24/7 emergency number: ) there are significant risks of contamination to the water system or there is disruption of service to high risk facilities; such as, hospitals and care facilities. C) Notifying customers according to the ERCP Note 2 Bacteriological Sampling One set of samples collected downstream of the repair site and at intervals of approx. 200 ft within the length of pipe that was shut down (if direction of flow is not known, samples shall be collected on either side of the repair site) If bacteriological results are unsatisfactory, flush and resample the repaired watermain If bacteriological results are still unsatisfactory, disinfect, flush and resample the repaired watermain References: AWWA (2015), AWWA Standard C651-14: Disinfecting Water Mains Water Research Foundation (2014), Project No 4307: Effective Microbial Control Strategies for Main Breaks and Depressurization Prepared by Vancouver Coastal Health, December Page 28 of 31

29 APPENDIX 6 MUNICIPAL UTILITY OPERATORS CERTIFICATION Page 29 of 31

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31 APPENDIX 7 PERMIT TO OPERATE Page 31 of 31