Wednesday, August 1, 2012
Other than water, what does the rain bring?
No alarm needed this morning. Thunder was crackling and rain falling well before the 6 a.m. clang of the set clock. Rainfall on the eastern shore evokes different feelings for different people. Farmers, for example, are happy that their parched corn might survive to adulthood. My mind then moves to the ramification of the rain in the Chester River Watershed, where the drops hit and and, ultimately, what it collects as it flows down hill off the fields and into the Bay. It’s a light rain so it’s unlikely that there will be runoff. Where will the water end up and what will it bring with it?
Yesterday I was over at Foremans Branch on Chino Farms in Chestertown talking with Ted Kimble and Henry Davis about siting a most sophisticated water quality sampling station. Ted’s going to work with Choptank Electric to drop the electric service in, that will power the station. Henry will work his magic clearing the long grass and shrubs so the system can be installed and serviced without a threat of contracting poison ivy. We’re talking with Dr. Jim Gruber to make sure that this project doesn’t interfere with his bird banding research. We also had to know how high the water gets during slamming rainfall that happens during Nor’easters and hurricanes. So much to do before we take our first sample.
The fancy gizmo will pump water quietly from Foremans Branch to the sensors and then gravity will whisk it back to whence it came. The sensors will let us know what is coming off of the fields and through the grounds from the farm, woods, and grasslands into the water. During dry times we’ll know that the contributions we’re measuring are leaking into the water through the ground. When it rains we originally would have expected to see spikes in stuff coming into the water because of runoff. Our friend Judy Denver up at USGS says that’s probably not the case. We’ll likely see water quality improve during these “freshets”. That’s because the additional water dilutes the nutrients and other “additives” from the farms and roads. Even though the water quality improves, the volume of water flowing through the system is so high that, overall, the amount of extraneous materials entering the system is still elevated. Look at it this way. If you have a gallon of water with a pound of sugar in it, it tastes like sugar water. If you have five gallons of water with two pounds of sugar in it, there is more sugar, but it doesn’t taste as sweet. So rain and runoff probably worsens water quality. Doug, did you say “Probably?”. Yes, I did.
Once we install this Hach Water Quality measuring station we’ll investigate the truth of this assertion. Water temperature, salinity, conductivity, pH (acidity), dissolved oxygen, turbidity (how dirty the water is), nutrient content, and water level data will be sent to our website every fifteen minutes. Coupled with a weather station on the farm we’ll be able to see the relationship between rainfall and water quality. Communicating with the farm we’ll be able to see how farming practices, including fertilizer application, relates to changes in the chemistry of the water flowing through Foremans Branch down to the Chester River. We’re hoping to have this information on line for everyone to see. This will change that "Probably" to an answer with more certainty. I’ll let you know when we throw the switch. Get in touch if you have questions. Doug Levin is the Associate Director, Center for Environment & Society @ Washington College and can be reached at firstname.lastname@example.org.
This is the site where we originally thought the water quality installation was going.