QCBFD Water System Update June 2020
Take Home Message RIDOH Absolute Mandate April - May 2020 1. Immediate chemical (chlorine) disinfection 4-log compliant well #1 a. This is an unprecedented concession by RIDOH 2. Submit plans for Pumphouse expansion to DEM/CRMC by June 2021 3. Iron amelioration or third low-iron source well decision by July 2021 4. Terms of execution under ongoing negotiation 5. Chemical 4-log disinfection is NOT negotiable
Take Home Message Once Well #1 achieves 4-log disinfection 1. Boil water advisory will be lifted Unlikely this will happen before September ○ 2. Well #1 will be the ONLY well providing daily water 3. Community MUST conserve water during peak season water demands Months of July and August especially July 4th weekend ○ 4. If Well #2 is required for supplementation or redundant backup Boil Water Advisory will be reinstituted ○
Take Home Message 1. E Coli has NEVER been isolated from the distribution system and has been cleared from Well #2 since October 2019 2. Well #1 sampling continues to show Total Coliform a. Basis for ongoing Boil Water Advisory (BWA) 3. To date, even though we remain on a BWA, water sampling has NEVER revealed E Coli in the distribution system 4. Sampling has NOT revealed ANY bacteria within our distribution system since November 2019 5. Simply put, the water coming out of your faucet has been bacteria free since November 2019
Public Works Committee 1. Committed to providing the community with safe drinking water 2. Immediately removed Well #2 (E Coli) from the water system 3. Engaged three Professional Engineering Firms a. Northeast Water Systems (Essex, RI) i. Water System Operator b. C&E Engineering (Woonsocket, RI) c. WSP Engineering (Madison, CT) 4. With our consultants we have been able to negotiate a path forward with RIDOH
Public Works Committee 1. Given shallow ground water source wells there is significant potential for future water quality, not water quantity, issues 2. 4-log non-chemical disinfection, i.e. UV system a. RIDOH will NOT allow nonchemical 4-log disinfection 3. Chemical 4-log disinfection system for our water source a. Significant technical issues i. Chlorine Disinfection Byproducts (CDP) ii. High iron in Well #2 iii. Constrained well field 4. PWC is committed to a system design which will protect our water quality for years to come
PW Committee options for CBP and Iron amelioration 1. CBP reduction 185 nm UV pretreatment a. Reduces Total Organic Compounds for CBP control 2. Media Filtration a. Will only address elevated iron levels i. Looking at year over year maintenance and operating costs ii. Researching parasitic water loss 3. Membrane Filtration a. Manufacturer needs to determine if system will work for our situation b. Will address several water quality issues:Iron, Nitrates, Organic Compounds, turbidity and bacteria i. Looking at year over year maintenance and operating costs ii. Researching parasitic water loss 4. Sourcing a third well, low-iron, in present wellfield a. DEM/CRMC and RIDOH permitting. No assurance iron levels will remain low
Outline Background ● Definition of terms ● What happened ● What has been done ● Technical issues ● Where do we go from here ● FAQ ●
Background The Central Beach water system is licensed by RIDOH as a Public Water System #RI1647512 to operate a Community public water system; we are subject to and must comply with various regulatory requirements, including: A. Rhode Island’s Rules and Regulations Pertaining to Public Drinking Water [216-RICR-50-05-1] B. Federal Government’s Safe Drinking Water Act C. Federal EPA Total Coliform Rule D. Federal EPA Ground Water Source Rule
Federal EPA Total Coliform Rule (TCR) The Total Coliform Rule (TCR), a National Primary Drinking Water Regulation (NPDWR), was ● published in 1989 and became effective in 1990. The rule set both a health goal (Maximum Contaminant Level Goal (MCLG)) and legal limits (Maximum Contaminant Levels (MCLs)) for the presence of total coliforms in drinking water. EPA set the MCLG for total coliforms at zero because there have been waterborne disease outbreaks ● in which researchers found very low levels of coliforms. The MCL levels are based on the positive sample tests for total coliforms (monthly MCL), or for total coliforms and Escherichia coli (E. coli) or fecal coliforms (acute MCL). The purpose of the 1989 TCR is to protect public health by ensuring the integrity of the drinking water ● distribution system and monitoring for the presence of microbial contamination. Applies to ALL Public Water Systems ●
Federal EPA Ground Water Rule (GWR) The EPA issued the Ground Water Rule (GWR) to improve drinking water quality and provide protection from disease-causing microorganisms. Water systems that have ground water sources may be susceptible to fecal contamination. In many cases, fecal contamination can contain disease causing pathogens. The purpose of the Ground Water Rule (GWR) is to reduce disease incidence associated with harmful microorganisms in drinking water. The GWR applies to public water systems that use ground water as a source of drinking water. The rule also applies to any system that delivers surface and ground water to consumers where the ground water is added to the distribution system without treatment. The GWR was published in the Federal Register on November 8, 2006.
Background on Testing Requirements The TCR and GWR require we obtain monthly samples of both wells and the distribution system (usually taken at a kitchen tap from a residence) If a well sample is positive ● Sample is repeated ○ If a distribution sample is positive ● Sample repeated ○ 2 further samples (one upstream and one downstream also obtained) for a total of 3 ○ 4 positive samples in one calendar month trigger a Level 1 or 2 assessment ● + distribution samples high risk of triggering an assessment ○
QCBFD Water System Early History 1. Early & mid 1920s: Howard Thorp sell lots located in Quonochontaug Central Beach (QCB), Charlestown, RI. Deeds contain provisions for access to water lines to the properties.: 2. 1 930: QCB vote to form Quonochontaug Central Beach Fire District (QCBFD). The enabling legislation includes provisions among other things the right to “construct and maintain its own water works, mains, and other necessary apparatus for supply water within its limits for fire, domestic and manufacturing purposes” At this time the water system was seasonal 3. 1948: QCBFD agrees to acquire the water system properties from Thorp. At this time the system’s well and pump house were located in the area that is now the playground and ball field 4. 1948-9: Well #1 was developed (created) and a new pump house constructed in the current wellfield north of Seabreeze Avenue 5. 1965: Well #2 was added in the same area approximately 100’ west of Well #1
QCBFD Water System Modern History 1. 1982: The seasonal distribution system was converted to a year round system ; PVC pipe was laid for the distribution system 2. 1990: Two hydropneumatic storage tanks added to allow for water storage 1775 gallons each (1000 gallons usable storage per tank) 3. 1997: Pumphouse enlarged to allow for calcite pH adjustment system 4. 1999: Hydropneumatic tanks relined 5. 2008-2010: Major water system upgrade performed a. 8000 gallon storage tank installed with UV lamp to recirculate and sterilize water in storage tank b. Control panel for seamless well pump duty cycle control and improved online remote monitoring c. Upgraded water system pH and corrosion control treatment
Water System Storage Well 1 Tank 8000 Gallons Well Field 1 Pumphouse Well Field 2 Distribution Well 2 Well 1 and Well 2 are both shallow Groundwater Source wells
Well Water to Storage Tank Storage Tank Pumphouse 8000 Gallons Feed from Well 1 Particulate Water Storage Tank pH adjuster and corrosion Filter inhibitor for Copper and Lead Feed from Water Pumps Monitoring Control Panel Well 2
Water Tank to Distribution Storage Tank Pumphouse 8000 Gallons Water Pumps UV Disinfection Water Pump Recycling unit Control
Pumphouse (External)
Terminology Total Coliform (TC) ● ○ C oliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially harmful, waterborne pathogens may be present or that a potential pathway exists through which contamination may enter the drinking water distribution system. Presence of coliforms indicates the need to look for potential problems in water treatment or distribution. E Coli (EC) ● Fecal bacteria from human or animal waste considered to be harmful bacteria and require ○ immediate action. TC+, TC-, EC+, EC- ● Water sample results (return) are positive (present) for Coliform (TC+) and E Coli (EC+) or ○ negative (absent) for Coliform (TC-) and E Coli (EC-). Often reported as TC-/EC- or TC+/EC-, etc
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