AWWA JAW56577

The Idyllwild Water District (IWD) andPine Cove Water District (PCWD) aresmall California groundwater systemsdrawing from soft, mildly acidicsource waters with high carbon dioxide contentand dissolved inorganic carbon concentrations.After both systems exceeded one orboth of the lead and copper action levels in1993 and 1994, IWD and PCWD investigatedaeration as a way to increase pH andreplace inhibitor or other chemical additions.Following pilot-testing, full-scale deepbubble aeration systems went online in bothwater districts in October 1998. By January1999, IWD and PCWD easily met the leadand copper action levels. In addition, radon(Rn) samples from PCWD showed a 99%reduction in Rn levels, ensuring compliancewith upcoming Rn regulation. Furthermore,the use of aeration for corrosion controlsimplified treatment and improved waterquality in most respects.When source water chemistry is appropriate,aeration treatment offers a simple andinexpensive substitute for chemical dosingfor corrosion control of lead and copper.Many smaller water systems struggle withoperating chemical feed systems and selectingchemical dosages for phosphate corrosioninhibitors. For a modest initial capital investmentand with good planning, water systemswith the appropriate chemistry can use aerationto take the place of chemical dosing forcorrosion control while removing Rn beyondany regulatory proposals. The end result iscost-effective, operator-friendly treatmentthat can simultaneously resolve other potentialwater quality issues. Includes 33 references, tables, figures.

Product Details

Edition:

Vol. 94 - No. 3

Published:

03/01/2002

Number of Pages:

13

File Size:

1 file , 1.8 MB