Circuit Court’s decision on Hydrologic Connectivity Further Muddies the Clean Water Act

Several circuit courts heard cases this year as to whether entities needed a Clean Water Act (CWA) permit for discharges to groundwater that may enter a “water of the United States” via hydrologic connectivity. Another court decision on groundwater’s applicability to CWA this week has added an additional variation in the circuit courts.

This week’s split decision by the Sixth Circuit Court of Appeals held that the Tennessee Valley Authority was not required to obtain a permit for discharges reaching surface water via groundwater. The decision does not contend that groundwater is not hydrologically connected to surface water, but rather that groundwater is not a “point source” under CWA, and therefore CWA permits are not required.

The fourth, ninth, and sixth circuit courts each heard cases on the topic and came to conflicting decisions as to whether a CWA permit under the National Pollutant Discharge Elimination System would be required. CWA permits are traditionally only required for discharges to a “water of the United States,” which groundwater is not currently considered.

The conflicting court decisions raise the likelihood the U.S. Supreme Court may take up the issue to resolve whether CWA applies to “indirect” discharges to surface waters, such as those that may reach surface water through groundwater.

The U.S. Environmental Protection Agency issued an information request on the topic this year, and a task force of NGWA members prepared comments that were filed, while also noting states are best suited to regulate groundwater quality. The EPA is yet to take action since the request for comments. Congress expressed an interest in providing clarity on the issue at a Senate hearing earlier this year as well.