Daily Archives: August 12, 2014

Lake Mead drying up? Why are you surprised? It’s in a desert!

” Once-teeming Lake Mead marinas are idle as a 14-year drought steadily drops water levels to historic lows. Officials from nearby Las Vegas are pushing conservation but also are drilling a new pipeline to keep drawing water from the lake.” click here

Impact of source water quality on THM and HAA formation

Xue C, Wang Q, Chu W, Templeton MR The impact of changes in source water quality on trihalomethane and haloacetonitrile formation in chlorinated drinking water. Chemosphere. 2014 Aug 4;117C:251-255. doi: 10.1016/j.chemosphere.2014.06.083.

This study examined the formation of disinfection by-products (DBPs), including nitrogenous DBPs, haloacetonitriles (HANs), and carbonaceous DBPs, trihalomethanes (THMs), upon chlorination of water samples collected from a conventional Chinese surface water treatment plant (i.e. applying coagulation, sedimentation, and filtration). Reductions in the average concentrations (and range, shown in brackets) of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) from 4.8 (3.0-7.3) μg/L and 0.52 (0.20-0.81) μg/L in 2010 to 2.4 (1.4-3.7) μg/L and 0.17 (0.11-0.31) μg/L in 2012, respectively, led to a decrease in HANs and THMs from 5.3 and 28.5μg/L initially to 0.85 and 8.2μg/L, as average concentrations, respectively. The bromide concentration in the source water also decreased from 2010 to 2012, but the bromine incorporation factor (BIF) for the THMs did not change significantly; however, for HAN the BIFs increased because the reduction in DON was higher than that of bromide. There was good linear relationship between DOC and THM concentrations, but not between DON and HANs.

Click here for full paper (fee).