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City of Milwaukie Johnson Creek Facility
6101 SE Johnson Creek Blvd.
Milwaukie, OR 97206
Function and Facts
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Responsible for the supply and distribution of drinking water.
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Serves approximately 6,500 residential and commercial customers.
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System comprised of 100 miles of water lines, 3 storage reservoirs, 7 wells, 2 pressure boosting stations, and 2 treatment plants.
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Complies with all State and Federal regulations.
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Milwaukie’s wells are able to provide about 5.8 million gallons a day (mgd).
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The annual average daily demand is approximately 2.48 million gallons per day (mgd) in 2001.
Revenue Sources
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The Water Division's main source of revenue is water use fees.
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Water use fees can only be used to operate, maintain, and improve the water system.
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System Development Charges (SDC) are collected from developers and homeowners.
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SDC funds can only be used to improve the system where new development causes increased demand on the water system.
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Water Capital Reserve funds are water use fees that have been set aside for future capital projects, such as building a new intertie (i.e. an interconnection permitting passage of water between two or more water systems) or other major project, so that water rates don't have to be increased to pay for capital.
Why Be Concerned?
Most water systems in the United States and Canada have good sources of water and/or sophisticated treatment plants to convert impure water to meet drinking water standards. Millions of dollars are spent to make the water potable before it enters the distribution system so most water purveyors think that their supplies are not in jeopardy from this point on. Studies have proven this to be wrong. Drinking water systems may become polluted or contaminated in the distribution system through uncontrolled cross connections. Cross connections are installed each day in the United States because people are unaware of the problems they can create. Death, illness, contaminated food products, industrial and chemical products rendered useless are some of the consequences of such connections. As a result, many hours and dollars are lost due to cross connections.
What Is A Cross Connection?
A cross connection is a point in a plumbing system where the potable water supply is connected to a non-potable source. Briefly, a cross connection exists whenever the drinking water system is or could be connected to any non-potable source (plumbing fixture, equipment used in any plumbing system). Pollutants or contaminants can enter the safe drinking water system through uncontrolled cross connections when backflow occurs. Backflow is the unwanted flow of non-potable substances back into the consumer’s plumbing system and/or public water system (i.e., drinking water). Backflow, to a certain degree, occurs continuously in every public water and/or plumbing system. There are two types of backflow: backsiphonage and backpressure. Backsiphonage is caused by a negative pressure in the supply line to a facility or plumbing fixture. Backsiphonage may occur during waterline breaks, when repairs are made to the waterlines, when shutting off the water supply, etc. Backpressure can occur when the potable water supply is connected to another system operated at a higher pressure or has the ability to create pressure, etc. Principal causes are booster pumps, pressure vessels, elevated plumbing, etc. Backflow preventers are mechanical devices designed to prevent backflow through cross connections. However, for backflow preventers to protect as designed, they must meet stringent installation requirements.
Where Are Cross Connections Found?
Cross connections are found in all plumbing systems. It is important that each cross connection be identified and evaluated as to the type of backflow protection required to protect the drinking water supply. Some plumbing fixtures have built-in backflow protection in the form of a physical air gap. However, most cross connections will need to be controlled through the installation of an approved mechanical backflow prevention device or assembly.
Some common cross connections found in plumbing and water systems include:
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Wash basins and service sinks.
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Hose bibs.
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Irrigation sprinkler systems.
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Auxiliary water supplies.
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Laboratory and aspirator equipment.
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Photo developing equipment.
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Processing tanks.
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Boilers.
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Water re-circulating systems.
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Swimming pools.
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Solar heat systems.
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Fire sprinkler systems.
For further information, contact your local water purveyor or the PNWS/AWWA Cross-Connection Control Committee through the PNWS office at (877) 767-2992.
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