You are here:
Surface and ground water quality in a restored urban stream affected by road salts
Citation:
COOPER, C. A. AND P. M. MAYER. Surface and ground water quality in a restored urban stream affected by road salts. Presented at The 2009 GSA Annual Meeting , Portland, OR, October 18 - 21, 2009.
Impact/Purpose:
to examine the impact of restoration on water quality
Description:
In 2001 research began in Minebank Run, MD to examine the impact of restoration on water quality. Our research area was to determine if road salts in the surface and ground waters are detrimental to the stream channel restoration. The upstream reach (UP), above the Baltimore I-695 Beltway, was restored in 1998/99, with post-restoration monitoring. The downstream reach (DOWN) was restored in 2004/05 with pre- and post-restoration monitoring. Stream gauges and piezometers were installed in the stream channel and floodplain of Minebank Run along multiple transects in both reaches. Statistical analysis identified significant differences in salinity (EC), the road salt related chemistry (Na & Cl) and secondary soil related chemistry (Ca, Mg & SO4) between UP and the greater concentrations in the DOWN surface water. Also identified were significant differences between the UP and DOWN ground water chemistry; the DOWN wells all have significantly greater salt concentrations than the corresponding depths in the UP wells. The DOWN ground water salts were significantly greater in the right bank (RB) than the left bank (LB) for Na, Cl, Ca and SO4 concentrations but Mg concentrations were greater in the LB. During wetter periods (e.g. during as road salts applications) associated research on the pre-restoration water levels had a toward the stream gradient, but during drought the RB could reverse gradient. The RB cation chemical composition was dominated by Na and was more variable than the Ca dominated LB. The restoration affected the groundwater quality. The DOWN-LB was completely restructured, leading to a significant decrease in the Na in the post-restoration wells. There are significant increasing Na trends in those LB wells. Significant increasing trends also occur for the Cl in these LB wells. Whether the current increasing trends will stabilize at the pre-restoration concentrations is unknown. If the continuously increasing trend in the surface water salinity is indicative, then well water trends are also expected to persist. Salt concentrations are not at levels which are detrimental to the stabilizing vegetation in this restored stream.
URLs/Downloads:
SURFACE AND GROUND WATER QUALITY IN A RESTORED URBAN STREAM AFFECTED BY ROAD SALTS
SURFACE AND GROUND WATER QUALITY IN A RESTORED URBAN STREAM AFFECTED BY ROAD SALTS.