AWWA ACE70890

This powerpoint presentation presents a case study of the City of Northampton,Massachusetts, operating an unfiltered public water supply system usingits surface water reservoirs until January 2008, via a filtration waiver granted by the MassachusettsDepartment of Environmental Protection (MADEP) in February 1996. Thewaiver was made possible because the City was able to comply with theSurface Water Treatment Rule criteria for avoiding filtration. However, inNovember 1999, the City reported an exceedance of six-month rollingaverage coliform concentration in its source water, thus exceeding theavoidance criteria. Also, distribution system samples indicated an average HAA5 level of 77 ug/L, exceeding theStage 1 Disinfection Byproduct Rule HAA5 limit of 60 ug/L. As a result,MADEP concluded that the system could no longer consistently maintainthe filtration avoidance criteria and could not meet the (then) recentlypromulgated Stage 1 DBPR limits. The City was issued an AdministrativeConsent Order requiring the construction of the Northampton WaterTreatment Plant. Coincident with the startup of this new WTP, the Cityhas initiated the IDSE sampling program designed to characterize DBPconcentrations within the distribution system. This paper summarizes data that demonstrates the financial and water quality impacts of convertingfrom an unfiltered public water supply to a modern, conventional facility. A before-and-after analysis of the impact on water user charges,compared to both the previous unfiltered system and to other communitiesin Massachusetts, is presented. This paper also serves as a case studyfor other utilities either currently operating with a filtration waiver orpossibly seeking a waiver as a result of reclassification to groundwaterunder direct influence (GWUDI) of surface water. Includes figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2009

Number of Pages:

34

File Size:

1 file , 1.5 MB