Water Supply/Chloramination Process

Water Supply Information/Chloramination Process
Response to Erin Brockovich Letter
Drinking Water Criteria Document for Chloramines

Erin Brockovich Letter
UPDATED - March 15, 2013 Press Release
UPDATED - Public Meeting Schedule and Locations
EPA’ History of Drinking Water Document
Water Supply System Timeline
Water Supply System Presentation
Plan Development Report Presentation
UPDATED - List of Community Water Systems using Chloramines
Additional Sources and Reference Literature
EPA’s Frequently Ask Questions and Answers Document


City of Broken Arrow Water Customer:

On August 20, 1979, the Broken Arrow City Council executed a thirty-one (31) year agreement with the Oklahoma Ordnance Works Authority (OOWA), a public trust, to purchase treated water disinfected with chlorine. The effective date of this agreement was January 1, 1982 and the corresponding original expiration date of the agreement was December 31, 2012.

Presently, this agreement has been extended through December 31, 2013 by amendment No.1 to the contract.

Nearly a decade ago, city leaders began the concerted effort to position the City of Broken Arrow for the future with respect to our water supply system.

On February 16, 2004, the Broken Arrow City Council formally established the Long Range Water Supply Committee and tasked this committee with the following responsibilities:
  1. to study and evaluate the community’s then-current water supply system
  2. to investigate, analyze, examine and develop potential alternatives of water supply
  3. to make recommendations to the Council in order to position the City of Broken Arrow for the future with respect to its water supply.

This committee consisted of local business and industry leaders within the community, residents and key city staff personnel.

During the course of the evaluation, the committee retained the professional engineering services from HUB Engineers, Inc. to investigate the community’s water distribution system. HUB developed a system-wide water model and calibrated the model against the recorded water usage at the time of modeling.

After countless hours of effort, the committee concluded for a 50-year planning horizon the city should consider taking advantage of the navigational channel of the Verdigris River that maintains a minimum water depth through an intricate system of locks and dams. This fixed water depth in turn established a controlled water level along the original Verdigris River where the City of Broken Arrow retains water rights granted by the Oklahoma Water Resources Board (OWRB).

This unique situation provides our community with a substantial amount of raw, untreated water that should be available even during times of increased drought conditions. With the growing national concerning about the potential effects of climatic change specifically on water resources, the City of Broken Arrow is uniquely positioned along a plentiful body of water that must be maintained at specific depth in order to provide sufficient amount of water to transport goods through the navigational watercourse.

In addition, the committee concluded a new water treatment plant was necessary to provide our community better control over our future with respect to water supply. In concert with the new plant, the committee recommended the city negotiate a contract to purchase supplemental water from either OOWA or another secondary water source such as the Tulsa Metropolitan Utility Authority (TMUA).

On March 6, 2006, the City Council adopted the above recommendations of the Long Range Water Supply Committee. Shortly after the approval of this plan, the City began conducting a source water analysis and performing extensive bench-scale testing on the Verdigris River water.

By June 2007, the test results revealed one of the biggest challenges associated with the treatment of the Verdigris River water is the ability to control or minimize the potential for the formation of disinfection byproducts (DBPs) due to the use of chlorine products as the primary disinfectant.

Other alternatives were likewise investigated and examined during the course of this bench-scale testing including enhanced coagulation, use of chemical pre-oxidants such as chlorine dioxide, permanganate and powder activated carbon and the use of ozone for pre-treatment. Enhanced coagulation demonstrated positive results. The results of the chemical pre-oxidants demonstrated no clear benefits, while ozone demonstrated significant modifications and alterations in the aquatic organic matter. Ultimately, the City concluded the use of chloramines as the secondary disinfection process effectively stops the chlorination disinfection byproduct formation.

In addition to the bench-scale testing, the City also conducted pilot testing of four (4) different membrane filtration processes in accordance with Oklahoma Department of Environmental Quality (ODEQ) regulations.

On April 24, 2010, the ODEQ approves the Membrane Filtration Pilot Study Report. This approval effectively allows the City to design and subsequently construct a new state-of-art, membrane filtration water treatment facility.

After negotiations with OOWA for a supplemental, water purchase agreement proved to be unsuccessful, the City sought to negotiate an agreement with TMUA. On January 26, 2011, the City of Broken Arrow through its public trust, the Broken Arrow Municipal Authority, executed a forty year agreement with the TMUA to purchase up to 20 MGD of supplemental water with no minimum restrictions.

On February 7, 2012, the City through BAMA awards and authorizes the execution of a contract to construct a new 20 million gallon per day (MGD) water treatment plant to Crossland Heavy Contractors, Inc.

The work includes several critical elements such as a new 150 million gallon (MG) pre-sedimentation basin, modification to the existing pre-sedimentation basin to increase its capacity, a new raw water pump station and corresponding raw water transmission line, a pre-treatment basin, a membrane filtration and administration facility, a 6 MG clearwell for finished water storage, a high service pump station and a new enhanced lagoon system. The worked is scheduled for completion in July 2014 and is presently on schedule.