Some of the fondest memories from my youth involve helping my dad play "shade-tree mechanic" on a warm summer day. Now, keep in mind that this was back in the days before cars had computer systems, CD players, or OnStar systems. Back then when you locked your keys in your car you either had to find a trusty coat-hanger or a misguided-youth who just happened to have a "slim-jim" at his disposal.
No matter what seemed to be malfunctioning under the hood of our mammoth orange Pontiac, Dad would almost always begin his Saturday auto repair ritual by standing before the open hood, putting his arm around one of us kids...and with a trusty screwdriver in hand, begin pointing out the various components of the engine.
"Now let's see," he would say.
"The carburator seems to be carburating..."
"The alternator seems to be alternating..."
"The pumps seem to be pumping..."
"And the pistons...," he would say with a sly grin.
"Why they seem to be working just fine!"
We were always certain that this would be the time that dad would slip-up and say a word that we weren’t allowed to utter.
When it came to keeping the family car in top-shape, Dad always had a sense of humor and took a holistic, or broad-ranging, approach in order to keep his family safe.
As with our 1972 Pontiac Lemans, the most effective way to protect your drinking water customers is to implement a program that considers security from the "source to the tap." What the good folks over at the Environmental Protection Agency call a "multiple barrier approach."
A multi-barrier approach looks at all of the components that make up your treatment system so that one day you will be able to take your system manager by the hand and tell him:
"Now let’s see…”
"The filter seems to be filtering..."
"The pumps seem to be pumping..."
"The agitators seem to be agitating..."
"And the piston pump... Why it seems to be working just fine!"
In this issue of the Safe Drinking Water Trust eBulletin we will take a "holistic" look at multiple barrier approaches to public water (and health!) protection.
Additional Resources
Safe Drinking Water for Public Water Systems: An Overview of A Diligent Approach
www.gov.ns.ca/enla/water/docs/DrinkingWaterDueDiligenceOverview.pdf [1]
Drinking Water Security for Small Systems Serving 3,300 or Fewer Persons
www.epa.gov/safewater/watersecurity/pubs/very_small_systems_guide.pdf [2]
From the Source to the Tap and Everything In Between
Implementing drinking water protection from "source to tap" is generally referred to as the multi-barrier approach. In this scenario, multiple barriers are put in place to stop contamination along the drinking water delivery system.
A multi-barrier approach looks at all of the components of a drinking water system and identifies safeguards needed to create trust and provide safe drinking water. The components include source water protection, drinking water treatment, and distribution systems. The safeguards will include management, technical barriers, and education.
The multi-barrier approach is an integrated system that prevents or reduces the contamination of drinking water, from source to tap, in order to reduce risks to public health.
On their own, each of these safeguards may not be counted on to prevent contamination, but together they offer greater assurance that drinking water will be clean, safe, and reliable.
The "barriers" generally referred to by drinking water security experts are:
Risk Prevention: Focuses on the selection and protection of your drinking water source
Risk Management: Focuses on the protection provided by water treatment and system operations
Monitoring and Compliance: Focuses on your system's ability to detect and fix problems in the source and/or distribution systems
Individual Action: Awareness and education of your consumers
In a nutshell, we are talking about good ol' capacity development—the development of your system's technical, managerial and financial ability to provide safe and affordable drinking water to your customers.
Additional Resources
EPA's Small System Capacity Development Guide
www.epa.gov/safewater/smallsys.html [3]
The Association of State Drinking Water Administrators (ASDWA) Capacity Development Links
www.asdwa.org/index.cfm?fuseaction=Page.viewPage&pageID=764 [4]
Risk Prevention
The best way to protect drinking water is to keep contaminants from entering source water. Multiple federal, state, and local laws, programs, and individual actions help communities identify sources of drinking water and potential threats. This work enables communities to take appropriate steps to protect the watershed.
When selecting a source, systems should be aware of potential problems such as contamination caused by agricultural drainage, urban runoff and other factors.
When selecting sources, systems also should consider:
The basic quality of the raw water (Does it contain pathogens, high turbidity, or other harmful chemical elements?)
The risk of future contamination
The source's ability to meet your system’s future needs
Once you have a source in operation, it is important that you protect it. This can be accomplished through a number of watershed and water source protection activities including regulatory approaches, physical barriers such as fences and mandatory setbacks, and educational campaigns.
Additional Resources
EPA Source Water Protection Page
cfpub.epa.gov/safewater/sourcewater/ [5]
Pennsylvania Source Water Assessment and Protection Program
www.dep.state.pa.us/dep/deputate/watermgt/wc/Subjects/SrceProt/SourceAssessment/default.htm [6]
Risk Management
Public water systems are the first line of defense to reduce or eliminate contaminants in source water. The Safe Drinking Water Act, which regulates these systems, develops standards and provides guidance to help systems reach the goal of providing safe and reliable drinking water.
Systems must collect and treat water, hire trained and qualified operators and have an emergency response plan in case of natural disaster or terrorist attack.
In order to provide adequate protection water systems must:
Meet the appropriate state’s minimum design and construction standards
Develop asset management plans that provide for a sound infrastructure
Meet all state and federal drinking water standards
The risk management portion of the multiple barrier approach also requires a commitment to developing and establishing appropriate security tools and developing an Emergency Response Plan (ERP) that shows how the system will respond in an emergency.
Additional Resources
National Science Foundation (NSF) Water System Risk Management Guide
www.nsf.org/business/newsroom/pdf/RiskManagement.pdf [7]
Virginia Water Resources Research Center Risk Management Guide
www.vwrrc.vt.edu/sws/infosources.asp?page=riskmgt&show=Government-United_States [8]
Monitoring and Compliance
Dealing effectively with risks to drinking water requires constant evaluation of the water quality. Water is monitored at the source; at the treatment plant, after it has been treated and disinfected; at the distribution system, which delivers water through pumps and pipes to your customers' homes; and in some cases, at the consumer's tap. Remember, when systems have difficulty meeting regulations and providing safe, reliable drinking water, enforcement actions can be (and generally are) taken by the state primacy agency.
Even if your system receives its water from the purest mountain streams…it is important that you follow all state and federal monitoring guidelines. All it takes is a small break down in your distribution system to create a big problem. In particular, contamination of treated water can be caused by:
Line breaks
Low water pressure
Problems with storage tanks
Cross-connections
Any good monitoring and compliance barrier will definitely include a cross-connection and control program.
A cross connection is any physical connection between the public water supply and any piping or arrangement that contains any foreign liquid or substance. A cross connection creates the potential of contamination of the public water supply as a result of backflow.
Backflow is literally the reversal in the normal direction of flow within a water system which can turn a cross connection into a health hazard. This can occur when water systems are working on lines or at times when water pressure is lost.
According to the EPA, this reversal of pressure in a water system may be "freakish and unpredictable."
Generally, the best way to prevent cross connections from being a problem is to identify potential sources of backflow and require that backflow-prevention devices be installed. The legalities of requiring these devices to be installed and that all systems being connected to your water distribution system meet certain requirements can be addressed by implementing a CCC (Cross Connection Control) policy for your system. For help developing your own CCC policy, see the resources listed below.
Additional Resources
University of Southern California Study: Prevalence of Cross-Connections in Household Plumbing Systems
www.usc.edu/dept/fccchr/epa/hhcc.report.pdf [9]
EPA's Cross-Connection Control Manual
www.epa.gov/safewater/pdfs/crossconnection/crossconnection.pdf [10]
Individual Action...The Final Barrier!
Constant vigilance to protect water before it becomes your drinking water is essential and involves all of us. An informed, involved and supportive public is the foundation of drinking water protection.
What we do in the watershed can directly impact the quality of water that arrives at the treatment plant. The more you know about drinking water, the better equipped you are to help protect it.
The best way to utilize the support of your customers is to educate them on the importance of protecting our drinking water sources.
Take the time to remind them that whether your tap water comes from surface or ground water, all drinking water sources are vulnerable to a variety of contaminants from a variety of activities.
The origin of contaminants might be in their neighborhood or many miles away. When rain falls, it picks up and carries away pollutants, depositing them into lakes, rivers, wetlands, coastal and even underground sources of drinking water. Because we know these activities have the potential to contaminate the source of our drinking water, we must enforce and support these four major barriers to protect our source water from contamination.
Preventing pollution is critical to protecting drinking water from contamination and reducing the need for costly treatment. Community involvement and individual action are key to providing a safe supply of drinking water.
So, talk to your community members and educate everyone about the importance of taking care of your drinking water source!
To learn about the sources of water in your community and sources of pollution, go the EPA's "Where you live: Search your community" website and enter your zip code to view detailed information about where the water from your shower head came from and what might be in it. Go to:
epa.gov/epahome/commsearch.htm [11]