Winter discharge of coalbed methane water in the Powder River Basin, Wyoming

ABSTRACT

The heat transported with coalbed methane (CBM) water is shown to influence the thermal, flow, and ice characteristics of the Powder River, the principal river draining the Powder River Basin, Wyoming, during winter. The writers suggest how management of CBM water discharge from numerous tributary streams will minimize potential adverse influences on river channel stability and ecology. Their study, conducted over two winters (2009–2010 and 2010–2011), indicates that besides augmenting the river's natural flow, a substantial winter influence of CBM water discharge was the formation of open-water leads typically extending up to several kilometres along the river. The leads result from warm coherent plumes of CBM water discharge that gradually cool and dissipate when exposed to frigid air. Lead formation alters flow thalweg alignment, concentrating flow along the lead, and plays a potentially significant role for biota along the river. The leads were observed to attract fish, birds, and other wildlife during winter.

Keywords:

• Coalbed methane
• product water
• ice
• channel stability
• eco-hydraulics

Additional information

Funding

This work was supported by the US Geological Survey, Wyoming Water Research Program [DOIUSGS43613P27].