March and April are typically very busy months for the Ground Water Investigation Program of the Montana Bureau of Mines and Geology (MBMG). Ongoing projects in the Gallatin Valley provide an excellent example.
In March, a team led by Tom Michalek conducted a synoptic run of the streamflow measurements on the Gallatin River, the East Gallatin, and other major tributaries. Over the two days, the team - consisting of personnel from MBMG's Butte and Billings offices - used acoustic doppler and electromagnetic technologies to put together a snapshot of flow conditions in the northern Gallatin Valley. During this time of year, not much is happening in the way of natural flow changes or irrigation diversions, so this is a great time to collect data on hydrologic relationships among tributaries, streams, and groundwater. These data also increase our understanding of general stream behavior, including identification of gaining and losing reaches, inputs from springs and groundwater, and seasonal variability of flow.
In addition, two week-long aquifer tests were conducted in April near the town of Belgrade, MT. These tests consist of pumping a single well at a constant rate, and measuring the consequent effects on water levels in the pumped well, in addition to nearby wells across the landscape. Hydrogeologists use this information to estimate flow properties of aquifer materials and the hydraulic connection (or separation) between different layers of the aquifer.
These are common field research activities for MBMG water scientists working all over Montana. Keep a look out - maybe you'll see them out there!