Taking a watershed view of Watkins Creek

Did you know you live in a watershed? Everyone does! When rain falls onto the ground, it has to go someplace - the low spot in your yard, a pond, a nearby stream or river. The area draining into that low spot, pond, stream, or river is called its watershed.

Watkins Creek’s watershed includes most of the southern half of Spanish Lake as well as portions of Bellefontaine Neighbors, Glasgow Village, and Black Jack. If you live, work, go to school, worship, or shop south of Parker, north of I-270, and east of the North County Recreation Complex, your home, business, school, or place of worship is likely to be in Watkins Creek’s watershed. The watershed extends a little south of I-270 east of Lewis and Clark, up to the top of the first ridge south of the highway. The watershed comprises about 4,309 acres of land. The main channel of Watkins Creek originates across Parker from the Pennyrich Farms subdivision and travels about 6.1 miles to the Mississippi River, into which it drains.

When rain falls anywhere within Watkins Creek’s watershed, eventually it will flow into Watkins Creek, carrying along with it litter, loose soil, or harmful substances like oil, road salt, animal wastes, or sewage. Too much of any of these can impair the water quality of Watkins Creek and its tributaries, making it difficult or impossible for fish and other wildlife to live in the stream. Children or adults who may be using Watkins Creek or its tributaries for recreation could be harmed if some pollutants are present at high enough levels.

The Clean Water Act of the EPA requires all waters of the U.S., including Watkins Creek, to be fishable and swimmable. Each state sets standards for pollutants that violate the Clean Water Act. For any pollutant exceeding the standard set by the Missouri Department of Natural Resources, the stream is put on the so-called 303(d) list for that pollutant. Once that happens, DNR is supposed to develop a plan to reduce the level of that pollutant.

In Watkins Creek’s case, it is on the 303(d) list for two pollutants, E. coli bacteria and chloride. E. coli bacteria exist in the digestive tract of animals, including humans. Because E. coli enters a stream from animal and human sewage, they serve as a marker for the presence of sewage, which may contain other kinds of dangerous organisms. Watkins Creek exceeds DNR’s standard for E. coli.

It also exceeds DNR’s standard for levels of the chloride ion. The chloride ion comes from salt. While any stream has a small amount of naturally occurring salt in it, if the salt content gets too high, it kills the small insects, snails, worms, and other small aquatic animals that serve as part of the food web in a stream, which leaves some fish with nothing to eat. The most likely source of excess salt in a stream is salt applied to de-ice roads, sidewalks, driveways, and parking lots during the winter. When the snow or ice melts, the salt dissolves in it. The salty water enters the storm drains that drain into the Watkins Creek system. Other possible sources of excess salt are improperly stored road salt (large amounts of salt are stockpiled by municipal and county street departments for winter use; if these piles are not properly contained, salt can enter the environment), industrial waste drainage, and human sewage or animal waste (both contain some salt).

DNR monitors for these pollutants only near the mouth of the creek. Watkins Creek has several unnamed tributaries, smaller streams feeding into Watkins Creek, as well as many small drainageways entering the creek from different parts of the watershed. In order to reduce E. coli and chloride levels in Watkins Creek, we need to have some idea of how these pollutants are distributed across the watershed. Are there some parts of the watershed that contribute most of the E. coli or most of the salt? Knowing this would help to develop a good plan to reduce these pollutants.

For this reason, our Stream Team has monitored several different sites throughout the watershed as part of the Cooperative Stream Investigation project mentioned in the first post of this blog. The next few posts will look more closely at some of the sites.

The Critters of Watkins Creek

On October 19, our Stream Team sampled for macroinvertebrates at one of the sites that we monitor, at the east end of Coal Bank Road. We kicked up the creek bottom in order to trap the macroinvertebrates (invertebrates such as insect larva, snails, and worms that are large enough to see without magnifying equipment), herein after referred to as critters, in a net. We also rubbed the larger rocks in the sampled area in order to dislodge and collect the critters that make rocks their home. Then we sorted them out and counted how many of different kinds of macroinvertebrates we found in the portion of creek bottom that we stirred up. After counting, and photographing a few of the critters, we returned them back to the creek so they could continue to live their lives.

One of the good things about counting critters is that it’s easy to do. We only need to be able to stir up the bottom and rub on rocks, hold the net in place, see the critters on the net, and move them into the collection container (ice cube trays) with tweezers. Children can do it as well as adults. Another good thing is that many of the critters we study spend several weeks to months living in the creek bed. Some of them, like mayfly and stonefly larva, are very sensitive to harmful changes in water chemistry during the time they are larva. Some others, like aquatic worms, can live even in water so polluted that nothing else survives. By counting the different kinds of critters, then using a scale that Missouri Stream Team developed that rates each kind of critter for how sensitive it is, we can determine if Watkins Creek has excellent, good, fair, or poor water quality. If the sensitive critters are there, it means the water quality has been good for the last several months. You can learn more about water quality monitoring and the Missouri Stream Team programs from their website. Besides all that, it’s fun to play in the creek! How often do we adults get to do something fun that also does good?

How does Watkins Creek rate? Unfortunately, not as well as we’d like. At best it has fair to good water quality at the lower end of the stream. And the water quality may be on a downward trend; 2010 and 2011 data show fewer kinds of critters than does the 2008 and 2009 data, rating only fair both years. If this is so, we don’t know why.

Here’s a photo of three of the mayfly nymphs we found.

You can see the gills on the abdomen (between the legs and the tails) of the nymph on the upper left. Mayfly nymphs breathe with their gills like fish do. Most kinds need good water quality in order to live and thus are considered a marker of good water quality; some kinds can live in lower-quality water. I don’t know what kind of mayfly nymphs these are, however. Mayfly adults are delicate-looking flies that live only a very short time, hours to a few days. The nymph stage can live for several weeks to months.

Here’s a photo of a damselfly nymph.

In this case its gills (more properly, lamellae) are the three tail-appearing structures on its back end. Damselfly nymphs are considered somewhat sensitive to pollution but less so than mayfly nymphs. Adult damselflies look similar to dragonflies, but hold their wings more toward the vertical when at rest than dragonflies do.

And here is a picture of the area that we monitor, looking upstream. This is one of the nicest locations that Watkins Creek has to offer, and it’s easily accessible off of Coal Bank Road.