AWWA MTC93028

The City of Brighton, Colorado, has a primary water supply of five shallow alluvial wells located within 1 1/2 miles of the South Platte River. The principal water quality concern is nitrate. The city studied reverse osmosis using various types of membranes for the following objectives: 1) confirm nitrate rejection values and stability; 2) determine THM precursor rejection values; 3) assess the long-term fouling tendencies of the raw water; 4) evaluate the relative fouling tendencies of the membranes; 5) confirm membrane performance projections for feed pressure and delta-P; 6) obtain concentrate water quality data required for the concentrate discharge permits. This paper discusses test results in detail, including membrane performance, nitrate rejections, conductivity rejections, THMFP precursor rejection, specific flux, feed pressure, delta-P, fouling tendency of raw water, and concentrate discharge permit data. The pilot tests demonstrated that RO could meet the city's water quality goals.