AWWA DPOC56514

The Stage 2 Disinfectants and Disinfection Byproducts Rule (D/DBPR) will require Community Water Systems to conduct an Initial Distribution System Evaluation (IDSE). The IDSE is intended to identify new compliance monitoring sites within the water distribution system that more accurately reflect sites representing high total trihalomethanes (TTHM) and haloacetic acids (HAA5) levels than those sites currently used for compliance. They will be based either on system specific monitoring or other system specific data that provides equivalent or better information on site selection. Systems will recommend new or revised monitoring sites to their State/Primacy Agency based on their IDSE study. For systems without DBP formation problems, conducting an extensive monitoring program to meet the IDSE requirements may yield little valuable information for the cost incurred. Water utilities in this situation may be better served by conducting a system specific study that produces information useful to the utility beyond fulfilling the requirements of the IDSE. In lieu of conducting an extensive monitoring program to identify distribution system locations with high DBP levels, the City of Golden, Colorado has conducted a system specific study as allowed by the Stage 2 Rule. This study will provide comparable or superior selection of new monitoring sites that target high DBP levels. In order to achieve this goal, two primary components must be understood: water quality changes and hydraulic conditions in the distribution system. This paper will present the integrated hydraulic and water quality model used to predict DBP formation in the Golden distribution system. This paper also focuses on distribution system modeling, along with operational issues. With regards to Golden, results of new monitoring site selection are discussed. Finally, recommendations are given for other utilities considering IDSE system specific studies.

Product Details

Edition:

Vol. - No.

Number of Pages:

2

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1 file , 92 KB