Your Watershed: Spending a day in the creek
June 17, 2017
I couldn't believe it. I watched as my phone slowly and gently sank its way to the bottom of Rifle Creek, in the clear, cold, and fast-moving water downstream of Rifle Falls.
It was mid-May and I was out with Nate Higginson, the watershed technician for the Middle Colorado Watershed Council, and Chad Mickschl, a hydrologist for the Bureau of Land Management. We were out collecting water samples along East Rifle Creek, West Rifle Creek, Rifle Creek and Government Creek.
The Middle Colorado Watershed Council collects water samples twice a year (once in the spring before peak runoff and once in the fall) for a multiyear study we are doing on Rifle Creek and its tributaries because of a 303(d) listing.
Section 303(d) of the Clean Water Act requires all states to assess the quality of their waters. Every two years, Colorado generates a list of rivers and streams that exceed water quality standards, known informally as the 303(d) listings. Any waters that exceed standards are considered impaired and are subject to further analysis and testing.
In previous testings, Rifle Creek was slightly high in selenium, a metal naturally found in sedimentary rock. As part of our multiyear study on Rifle Creek, the Middle Colorado Watershed Council is collecting data to determine if the high selenium level was a unique event (runoff could have been high at the time of testing, from heavy rain or excess snowmelt), if Rifle Creek is chronically impaired (runoff needs to be managed), or if levels of selenium fluctuate throughout the year and how that can be managed.
Interestingly, Rifle Creek was taken off the 303(d) listing in a recent testing cycle (meaning, the levels are within normal range again!), so now we are investigating if our data corroborates these findings.
Selenium can enter waterways through runoff, which includes natural weathering, irrigated lands and surface disturbance (a broad term that can mean everything from roads to mining). Without getting into too much geology, all the red rock sandstone and gray limestone that surround us in Garfield County is filled with selenium, because it is sedimentary rock. When water flows across our landscape and into the river, it carries with it soils and sediment and all the metals in that sediment. While runoff is a natural and expected process, there are ways to manage runoff and mitigate the sediment (and therefore contaminants) that enter our waterways.
As with many things in life, selenium is good in moderation. It is an essential metal, meaning animals cannot create it and need to get it from the environment. When levels get to be too high however, selenium can be toxic and there are reports larval deformities in aquatic invertebrates and toxic effects on fish eggs and reproduction.
Selenium is a common contaminant. In 2012, the state assessed 71,000 miles of rivers and streams throughout Colorado. Of those miles, 12,000 were found to have some impairment. Upon further breakdown of the impairments, selenium alone was responsible for about 7,000 miles, the most prevalent in the rivers by far. The next most prevalent was Escherichia coli, a bacteria found in the gut of warm-blooded organisms, including humans, contaminating about 2,000 miles of rivers or streams. The remaining contaminants were responsible for about 1000 miles or less each. This is to say, selenium, for better or worse, is common in Colorado.
Which brings me back to Rifle Falls.
Nate and Chad were actively in the river, collecting water samples to be sent to a lab to determine exact levels of metals, minerals, and other suspended solids that might be in the water. They also determined the flow of the river, what the river bottom consisted of, and the composition and quality of bank vegetation. I was on the bank collecting pictures, and occasionally using a sensor to determine water temperature and pH levels.
I extended my hand over the clear river, snapped a great photo of Chad and Nate, and then … plop.
The water was clear, and after the slow motion descent to the river bottom, I acted fast. I reached the 2 feet down, grabbed my soaked phone off, dried it off as best I could, set it in the sunshine and waited.
Now, after a good dry, and a lot of patience, it works great. I like to think that speaks well to the quality of the water, but we will give the final and official report when our study on Rifle Creek is complete. In the meantime, enjoy the rivers and streams this spring, just be sure to protect your electronics.
Annie Whetzel is the Community Outreach Coordinator at The Middle Colorado Watershed Council. The council works to evaluate, protect and enhance the Middle Colorado River Watershed through the cooperative effort of watershed stakeholders. To learn more, go to http://www.midcowatershed.org or go to facebook.com/midcowatershed.