Grand Forks County Soil Conservation District
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Grand Forks County Soil Conservation District
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Turtle River Watershed Assessment: Preliminary Data By: Kyle Glazewski Watershed Coordinator We are seeking assistance from individuals living in the Turtle River Watershed. We have a survey set up at http://turtleriverwatershed.speedsurvey.com The survey addresses water quality concerns and interest in cost share to implement conservation practices on land within the watershed. If you are interested in getting assistance for improvements to your Turtle River Watershed land, please take a few minutes and complete the survey. Overview As of November 2007, we have completed the field work portion of the Turtle River Watershed Assessment. This project began in December 2005 with the sampling of Larimore Dam. The field monitoring picked up with the spring runoff of 2006 and sampling of streams continued on a weekly basis during open water season through the end of the project. Winter sampling consisted of monthly samples taken at Larimore Dam. The following document will outline activities of the Turtle River Assessment including:
NOTE: This document is looking at the preliminary data. It is NOT intended to be an all-encompassing analysis of the project. This is merely to provide our land owners in Grand Forks County with some idea of what has been going on and an idea of what we’re seeing so far. More analysis needs to be done, but I wanted to provide an update to those who may be curious. Stream sampling Stream sampling was conducted on 8 stream sites located in the Turtle River Watershed. These sites were located north of Manvel across the county to Larimore (see map). During spring runoff (spring thaw thru the month of May), water samples were collected from each site twice per week. From June until November, water samples were collected once per week. Sampling was more frequent in the spring due to the higher rate of water movement which increases potential for pollution. The 8 stream sites each have a unique identification number, and the locations are: 385368—1 mile north of Larimore at bridge along CR-18 385387—located in Larimore Golf Course 385369—1 mile east and 1.5 miles north of Larimore rest area (N of Hwy 2) 385370— ~0.5 mi west of Turtle River State Park at bridge crossing on Hwy 2 385371—bridge 1 mile north of Mekinock on CR-3 385372—CR-11 at bridge 1.5 miles west of CR-5 385373—CR-11 at bridge 0.5 miles west of CR-5 385375—3.5 miles north of Manvel
Figure 1: General Watershed Map
Figure 2: General Map with Streams
Figure 3: Stream Sample Sites Testing Water samples were collected and shipped to the North Dakota Department of Health’s Environmental Laboratory in Bismarck for analysis. Each sample was tested for a wide array of variables including:
Total Suspended Solids (TSS): TSS are the solid materials, both living and non-living, that are found in the water. This includes soil, organic material, agricultural or industrial runoff. It is anything that the water is carrying (suspended). This variable is related to the clarity of the water. Phosphorus: Phosphorus is a necessary nutrient for plant growth. It is found in fertilizers, animal waste, industrial waste, septic tanks, storm sewers, and erosion from construction sites. Excessive phosphorus causes excessive aquatic plant growth and algal blooms to occur in the water. When these plant materials die and decay, they remove oxygen from the water, which will impair other living organisms such as fish. Nitrogen: Nitrogen is another nutrient necessary for plant growth. It is found in many of the same sources as phosphorus. Nitrogen can also cause excessive plant growth and removal of oxygen from the streams. Additionally, nitrogen can cause a condition in humans or other animals that limits the blood’s ability to carry oxygen, and the blood can look brown instead of red. Nitrogen can cause a shortness of breath in cattle, and nitrate poisoning can cause them to froth at the mouth, suffer convulsions, appear blue around the muzzle and have a bluish tint around the eyes. Moderate poisoning is believed to cause poor growth, infertility, abortions, and vitamin A deficiencies. Fecal Coliform: Fecal coliform is found in agricultural or storm water runoff and pet wastes. Animal feeding operations can be a major source of fecal coliform if runoff is allowed to flow into streams, or if cattle are wading in streams while producing waste. A person swimming or wading in water contaminated with high fecal coliform levels can get sick by swallowing the water, or getting water in cuts in the mouth, nose, ears, or the skin. Diseases such as typhoid fever, hepatitis, gastroenteritis, dysentery, and ear infections can be caused from high fecal levels. Charts with data will be updated soon!! Posted:6/5/08
Field Testing In addition to the water sample collection, additional data was collected in the field. This information includes:
Riparian Assessment In September 2007, we conducted a riparian assessment on the Turtle River Watershed. 75 sites were randomly selected by the Environmental Protection Agency (EPA). At each site we conducted the Stream Visual Assessment Protocol (SVAP) and the Rapid Geomorphic Assessment (RGA).
Figure 4: Riparian Assessment Locations SVAP The Stream Visual Assessment Protocol is an NRCS tool used to evaluate the physical condition of the stream within the assessment area. There are several different factors that are evaluated.
Each of these factors will get a score between 1 and 10. The overall score will give us a rating from poor to excellent.
Figure 5: SVAP Scores Looking at the overall scores, there is a high percentage of sites that are in poor condition according to our SVAP scores. We definitely have room for improvement in the watershed. Riparian zones would be the focus when we look for solutions to improve the SVAP scores. Riparian areas are going to add habitat for fish, insects, and other invertebrates. These areas are also going to help reduce nutrient enrichment and sedimentation problems within the streams. The Rapid Geomorphic Assessment (RGA) is a tool developed by the National Sedimentation Laboratory. RGAs were developed to provide a means of assessment through which the geomorphic mechanisms acting upon a stream channel at a particular site can be gained at a particular point in time. In other words, RGAs are used to judge how much erosion and deposition is taking place within a stream’s reach. More unstable streams tend to be eroding and down cutting (incising) quite a bit, which can lead to unstable stream banks. Knowing the stability of a stream may help to determine if Best Management Practices (BMPs) or bioengineering techniques should be used to help prevent erosion. Several factors were considered when assessing the stream’s stability such as: 1) Primary bed material—is the bottom of the stream primarily clay, silt, sand, gravel, boulders, or bedrock? Larger materials such as gravel or boulders provide more stability. 2) Degree of incision—is the stream downcutting (eroding)? 3) Degree of constriction—is the stream narrowing as it flows downstream? 4) Streambank erosion 5) Riparian woody vegetative cover—is there sufficient plant material to help hold the soil along banks in place? 6) Occurrence of bank accretion—is the stream depositing material on its banks? 7) Simon’s Channel Evolution Model—streams change constantly, and they can be classified into 6 stages based on how much erosion, deposition, downcutting, or widening is taking place with the stream. Stages 1, 2, and 6 are generally stable. Stages 3, 4, 5 are generally unstable. See below for more details. (Channel Evolution Model image, USGS 1992)
Simon's Channel Evolution Model - image from http://www.stormh2o.com/sw_0503_identifying_a.html The six stages of Simon's Channel Evolution Model are as follows: Stage I: The
waterway is a stable, undisturbed natural channel. noted from http://www.ars.usda.gov/is/AR/archive/dec03/state1203.htm
Figure 6: RGA Stability
Figure 7: RGA Stream Stage As you can see from the maps, there are a lot of unstable areas along the Turtle River and its tributaries. We will have to consider the stability and stage of the stream when deciding what BMPs to implement. Stage 4 streams are the most difficult to implement BMPs because they are actively downcutting and widening. If a stream is at a stage 1, it will be easier to work on. If your area of the stream is unstable and a stage 4, it doesn’t mean we don’t want to put in any BMPs, it just means that we need to carefully consider our options, so we do not waste time and money putting in something that probably won’t work. Each situation is unique, and would have to be evaluated for each interested land owner. Watershed Info: |
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