The Susquehanna River Basin Commission (SRBC) on Thursday released a report detailing existing or baseline water quality conditions in most of its small watersheds within the basin, which overlies the Marcellus Shale.

According to its 16-page report, the SRBC is initially focusing on data collected from monitoring stations at 37 priority watersheds within the basin, mostly smaller streams in northern Pennsylvania and the southern tier of New York. The basin has 51 watersheds.

The SRBC said it started collecting data from the watersheds in 2010 when it formed the Remote Water Quality Monitoring Network (RWQMN).

“One of the objectives of the RWQMN is to determine if natural gas development and/or other activities are causing adverse impacts on water quality,” SRBC Executive Director Paul Swartz said. “As with any rigorous, data-based monitoring effort, this is not a short-term process, and so we have been letting the science dictate our schedule.”

“By letting the scientific process play out, we now have good, solid baseline water quality data on 37 of the 51 monitoring stations. As a result, if water quality conditions change in the future, the comparative data will help us determine if the changes are within normal ranges or likely caused by pollution events related to natural gas drilling or other activities.”

According to the SRBC, every monitoring station is equipped with sensors measuring water temperature, pH, dissolved oxygen, conductance and turbidity. The commission said it would also periodically collect water samples on-site for use in more than 20 additional tests in a laboratory.

The SRBC said local anomalies would require more in-depth analysis at six of the 37 initial test sites, all in Pennsylvania. Those test sites are Blockhouse Creek in Lycoming and Tioga counties; Kitchen Creek in Luzerne and Sullivan counties; Trout Run in Clearfield County; Meshoppen Creek in Susquehanna and Wyoming counties; Starrucca Creek in Susquehanna and Wayne counties, and Bobs Creek in Blair and Bedford counties.

The anomalies included elevated pH levels at two monitoring stations and conductance spikes, also at two monitoring stations.

About 85% of the Susquehanna River Basin — which measures 27,510 square miles, including half of Pennsylvania and parts of New York and Maryland — overlays the Marcellus Shale. It is managed by the SRBC, a compact set up by the federal government in 1971. Representatives from the three aforementioned states and the Army Corps of Engineers serve as commissioners.