Water Treatment Plant

Water Treatment PlantThe City of Defiance Water Treatment Plant draws water from the Maumee River to replenish its 74 acre upground reservoir. Water is then pulled from the reservoir to provide a constant, reliable raw water supply.
The Water Plant laboratory is certified by the Ohio Environmental Protection Agency (OEPA). All plant operators are also certified for chemical analyses. Three employees are also certified for bacteriological analysis.

This facility is a Class IV Water Treatment Plant. The Water Plant is staffed 24 hours per day, 365 days per year.


The City of Defiance Water Treatment Plant is designed to treat water by the following general process:

  1. Raw water enters the Outlet Structure at the reservoir where large debris, leaves, sticks, fish, etc. are removed.
  2. Sodium Permanganate is added prior to the plant for organic removal and to help with taste and odor control.
  3. At the Plant, ferric chloride (a coagulant) is added to help with settling and powdered activated carbon can also be fed at this location to provide additional treatment during an Algal Toxin or severe taste and odor event.
  4. The water flows to the flocculation basins where paddle mixers gently mix the water and chemicals to form particles (floc) which are large and heavy enough to settle out of the water stream.
  5. The water and floc then flow to the sedimentation basins where the floc settles out of the water stream. Settled solids are removed and pumped to sludge lagoons southwest of the plant.
  6. The settled water flows out of the resedimentation basins where ferric chloride (for coagulation) is added. It then proceeds to our four clarifiers where lime (for softening) is added. After mixing in the center of the clarifier, the clear water exits from the outer portion of the clarifier and the solids settles to the bottom. These solids also go to the sludge lagoons.
  7. The settled water then flows to the recarbonation basin where carbon dioxide gas is added to the water to adjust the pH to a neutral level and improve its stability.
  8. Following the recarbonation basin, Phosphate is added to prevent scaling and corrosion in the distribution system pipes. Next the water flows to dual media filters which filter out the particles which were too small and light to settle out in the sedimentation basins or clarifiers. When the filters become dirty, they are backwashed. The dirty backwash water is wasted to the backwash holding tank, and is recycled or pumped to the lagoons.
  9. After conventional filtration, the water proceeds to the Granular Activated Carbon System. This removes very small particles of organic matter, taste and odor compounds, as well as several other chemical contaminants that were too small to be removed in the prior processes.
  10. The filtered water then flows to the clearwells where chlorine is added for disinfection. The water remains in the clearwells for a period of several hours to provide enough contact time for complete disinfection. Fluoride is also added to the water as it enters the clearwells. This is supposed to prevent tooth decay.
  11. From the clearwells the finished water flows to the high service pump station where it is pumped to the distribution system.

Depending on the rate of flow through the plant, this treatment process can take from 12 to 25 hours. At an average daily flow of 3.8 million gallons per day (MGD), the treatment process takes 18 hours. The plant is capable of treating 8.0 MGD.

The Distribution system consists of over 110 miles of waterlines ranging in size from 16 inches to 2 inches with the majority being 6 inches. There are two elevated water towers with a combined capacity of 2 million gallons. There are approximately 1,026 fire hydrants. Defiance also supplies water to Brunersburg, Ayersville and Christi Meadows.

Call Before You Dig - It's the Law

Call 811 Before You Dig (Ohio Utilities Protection Service Website)For Water, Sewer, Electricity and Gas in Ohio call 800-362-2764 or 811.

Ohio law requires that anyone digging contact Ohio Utilities Protection Service (OUPS) at least 48 hours (excluding weekends and legal holidays) prior to beginning their work. Failure to contact OUPS could result in fines or penalties.