Sediment Science in Kansas

Photo courtesy of USDA, NRCS, Lawrence, Kansas

Introduction

In Kansas and nationally, sediment is a concern for both physical and chemical reasons. Physically, problems caused by excessive sediment may include degraded water quality, degraded aquatic habitat, increased water-treatment costs, decreased channel capacity, clogged water intakes, and loss of water-storage capacity in reservoirs. Chemically, sediment serves as a carrier for various contaminants and, under certain conditions, as a source of contaminants to water and biota. Sediment-associated contaminants include nutrients (nitrogen, phosphorus), trace elements, certain pesticides, and polychlorinated biphenyls (PCBs). Nationally, sediment has been identified as the most important contaminant of concern by the U.S. Environmental Protection Agency. In Kansas, concern about sediment is evidenced, in part, by the fact that the Kansas Department of Health and Environment has developed total maximum daily loads (TMDLs) to reduce sediment loads to several reservoirs in the State. Effective management of sediment requires an understanding of sediment erosion, transport, deposition, and quality and how such processes and characteristics vary spatially and temporally in response to various natural and human factors.

Results

Over the past several years, the USGS has completed several studies in Kansas that have examined various sediment issues including sediment erosion, sediment transport, sediment deposition, sediment quality, and sediment sources. Results of these studies are summarized below.

Sediment Erosion

Erosion is a concern for several reasons. Land-surface erosion removes topsoil, degrades soil quality, and contributes potentially harmful sediment to nearby streams. In-channel erosion of streams also is problematic. Channel-bank and channel-bed erosion represents a persistent threat to property, structures, and habitat located in or near stream channels. Erosion often is increased by various human disturbances including dam construction, channelization, land-use change (e.g., urbanization), and land-management practices (e.g., row-crop production, overgrazing). Nationally, billions of dollars have been spent over the past several decades to control erosion and mitigate its effects (Pimentel et al., 1995; Shields et al., 1995; Morris and Fan, 1998; Tegtmeier and Duffy, 2004).

Several USGS studies have investigated channel erosion in response to human disturbances. To address concerns about possible downstream effects of John Redmond Reservoir on the Neosho River, a study was done to determine whether or not the channel had widened substantially since the reservoir was completed. The post-dam response of the river was determined to be minor with no evidence of substantial widening (Juracek, 2000). In a study to assess the downstream effect of large reservoirs on channel-bed elevation, Juracek (2001) found that degradation lowered channel beds by several feet at some locations (fig. 1). Along Soldier Creek, it was determined that channelization caused substantial channel degradation (widening and deepening). The degradation migrated several miles upstream from the original site of disturbance (Juracek, 2002, 2004a). Additional information on these and other USGS studies is available at http://ks.water.usgs.gov/studies/fluvial/.

Figure 1. Channel-bed degradation in the Big Blue River near Manhattan, Kansas (stream-gaging station 06887000) downstream from Tuttle Creek Dam, as evidenced by change in river stage for the mean annual discharge (2,500 cubic feet per second), 1953-1997.

Sediment Transport

Effective management of sediment requires information on the amount of sediment being transported at specific locations and how sediment transport varies with time. Currently, the USGS operates a suspended-sediment monitoring network in Kansas that provides several types of useful suspended-sediment information. For example, continuous turbidity and streamflow data are used to provide continuous (hourly) estimates of suspended-sediment concentration and load (fig. 2). The information also is useful for evaluating variability in suspended-sediment load in relation to streamflow during individual runoff events, seasonally, and over the long term. Rasmussen and others (2005) used multi-year data from three continuous water-quality monitoring sites to estimate average annual suspended-sediment (and nutrient) loads and yields for the Kansas River. Suspended-sediment information also can be used to document and explain differences among sites (e.g., because of differences in basin characteristics including precipitation, soils, topography, and land management) as well as provide baseline information to assess the effectiveness of implemented erosion control practices. Information on the USGS suspended-sediment monitoring network for Kansas is available at http://ks.water.usgs.gov/rtqw/.

Estimated real-time
suspended-sediment load in Little Arkansas River at Highway 50 near Halstead, Kansas.

Figure 2. Estimated real-time suspended-sediment concentration in Little Arkansas River at Highway 50 near Halstead, Kansas (stream-gaging station 07143672).

Sediment Deposition

While in-stream sediment deposition may degrade aquatic habitat, the current priority concern regarding sedimentation in Kansas is lost water-storage capacity in reservoirs. In particular, sedimentation is a concern because it reduces the function of reservoirs for various important uses including water supply, flood control, and recreation.

Since 1996, the USGS has completed about 25 reservoir sediment studies in Kansas (fig. 3). Available information (projected through 2005) for five large reservoirs indicates that conservation-pool, water-storage capacity lost because of sedimentation ranges from less than 10 percent for Cheney Reservoir (Mau, 2001), Hillsdale Lake (Juracek, 1997), and Webster Reservoir (Christensen, 1999), to about 25 to 40 percent for Perry and Tuttle Creek Lakes (Juracek, 2003; Juracek and Mau, 2002). Among the smaller reservoirs, water-storage capacity lost because of sedimentation has been documented at about 50 percent or more for Crystal and Mission Lakes (Juracek, 2004b). Compared in terms of mean annual sediment yield from the basins, the five large reservoirs range from 0.03 acre-feet per square mile for Webster Reservoir to 1.59 acre-feet per square mile for Perry Lake (table 1). Sedimentation in Perry Lake has occurred at a rate almost twice as fast as originally projected by the U.S. Army Corps of Engineers.

Figure 3. USGS reservoir sediment studies in Kansas

Table 1. Mean annual sediment yield and mean annual precipitation for selected reservoir basins in Kansas. (source: Juracek, 2004b).

Reservoir basin	Sediment yield (acre-feet per square mile per year)	Mean annual precipitation (inches)
Small reservoir basins
Mound City Lake	2.03	40
Crystal Lake	1.72	40
Mission Lake	1.42	35
Gardner City Lake	.85	39
Otis Creek Reservoir	.71	33
Lake Afton	.66	30
Large reservoir basins
Perry Lake	1.59	37
Hillsdale Lake	.97	41
Tuttle Creek Lake	.40	30
Cheney Reservoir	.22	27
Webster Reservoir	.03	21

In an attempt to explain differences in sediment yield among reservoir basins in Kansas, Juracek (2004b) compared estimated mean annual sediment yields for 11 reservoirs with factors that affect soil erosion. Specifically, the factors included were precipitation, soil permeability, slope, and land use. The analysis indicated that only the relation between mean annual sediment yield and mean annual precipitation was statistically significant (at the 0.05 level of significance). That is, as mean annual precipitation increased, mean annual sediment yield also increased. Thus, for the 11 reservoirs included, mean annual precipitation was the best predictor of sediment yield. Given the pronounced decrease in precipitation from east to west across Kansas, a similar east to west decrease in reservoir sedimentation rates is likely.

Sediment Quality

Sediment quality is an important environmental concern because sediment may act as a sink for various contaminants and, under certain conditions, as a source of contaminants to the overlying water column and biota (Baudo and others, 1990; Zoumis and others, 2001). Examples of sediment-associated contaminants include phosphorus, trace elements, certain pesticides, and PCBs. Once in the food chain, some sediment-derived contaminants may pose an even greater concern because of bioaccumulation. Sediment-associated contaminants also are a concern because they tend to persist in the environment. For example, even after the source of a particular contaminant has been eliminated in a basin, it may take several decades before newly-deposited sediment in a reservoir recovers to baseline concentrations of the contaminant (Van Metre and others, 1998; Juracek and Ziegler, 2006). Information on sediment quality is important for reconstructing historical conditions, providing a baseline for future assessments, providing a warning of potential problems, understanding effects of human activity, and providing guidance for management (e.g., TMDLs). Important issues requiring sediment-quality information include reservoir eutrophication, aquatic habitat, and dredging.

The USGS has completed several studies of sediment quality in Kansas that mostly have focused on reservoir bottom sediments. Sediment concentrations of total nitrogen and total phosphorus varied substantially from site to site but typically were relatively uniform over time at specific locations. Trace element concentrations were spatially variable and substantially affected by human activity at some sites. Generally, arsenic, chromium, and nickel concentrations exceeded threshold-effects guidelines for toxic biological effects but were less than probable-effects guidelines. Conversely, cadmium, copper, lead, mercury, and silver concentrations typically were less than the threshold-effects guidelines. For zinc, the results were mixed. Human effects included copper concentrations increased above the probable-effects guideline by copper sulfate applications to control algal blooms, and lead concentrations increased above the threshold-effects guideline by the historical use of leaded gasoline (Juracek, 2004b). At one location affected by historical lead and zinc mining, cadmium, lead, and zinc concentrations were increased far above the respective probable-effects guidelines (Pope, 2005; Juracek, 2006). Organochlorine compounds (i.e., certain pesticides, PCBs) typically were either not detected or detected at concentrations less than the threshold-effects guidelines. The frequent detection of DDE indicated that the historical use of DDT was widespread in Kansas (Juracek, 2004b). Additional information on sediment quality in Kansas is available at http://ks.water.usgs.gov/studies/ressed/.

Sediment Sources

Of fundamental importance for reducing sediment loads and yields is a determination of the sources of sediment for a given stream or reservoir. The sediment-source question can be answered both geographically and geomorphically. The geographic aspect involves the quantification and comparison of sediment loads for selected basins through the establishment and operation of a suspended-sediment monitoring network. The geomorphic aspect involves a sampling, chemical analysis, and comparison of source materials (e.g., channel banks, cropland soils, and grassland soils) with suspended or deposited sediment to ascertain the relative contribution from each source. Determination of the sediment contribution from specific source types is necessary for the design of effective sediment management strategies (Walling, 2005). Because the relative contribution of sediment from different sources can vary within and between basins and over time, basin-specific information on sediment sources is needed.

Using a combination of several chemical tracers, an investigation of sediment sources for the Perry Lake Basin (northeast Kansas) indicated that, while the relative importance of channel-bank and surface-soil sources varied among the subbasin reservoirs, channel-bank sources were dominant for Perry Lake. Thus, the importance of channel-bank sediment sources increased with distance downstream in the Perry Lake Basin (Juracek and Ziegler, 2007).

Ongoing Studies

Characterization of suspended-sediment loading to and from John Redmond Reservoir, 2007-2009

Sediment is accumulating more quickly in John Redmond Reservoir than in other federal impoundments in Kansas. The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, initiated a study to characterize suspended-sediment loading to and from John Redmond Reservoir. Turbidity sensors were installed at two U.S. Geological Survey stream gages upstream (Neosho River near Americus and the Cottonwood River near Plymouth) and one stream gage downstream (Neosho River at Burlington) from the reservoir to compute continuous, real-time (15-minute) measurements of suspended-sediment concentration and loading. Real-time data from this study is available on the USGS real-time water-quality web page http://ks.water.usgs.gov/rtqw/. A report describing the results of this study is scheduled for publication in October 2008. Here is a spreadsheet of mean-daily values of streamflow, sediment concentration, and sediment loading calculated from 15-minute data.

References

Baudo, R., Giesy, J.P., and Muntau, H. eds., 1990. Sediments—chemistry and toxicity of in-place pollutants: Ann Arbor, MI, Lewis Publ., 405 p.

Christensen, V.G., 1999. Deposition of selenium and other constituents in reservoir bottom sediment of the Solomon River Basin, north-central Kansas. U.S. Geological Survey Water-Resources Investigations Report 99-4230, 46 p.

Juracek, K.E., 1997. Analysis of bottom sediment to estimate nonpoint-source phosphorus loads for 1981-1996 in Hillsdale Lake, northeast Kansas. U.S. Geological Survey Water-Resources Investigations Report 97-4235, 55 p.

Juracek, K.E., 2000, Channel stability downstream from a dam assessed using aerial photographs and stream-gage information. Journal of the American Water Resources Association, v. 36, n. 3, p. 633-645.

Juracek, K.E., 2001, Channel-bed elevation changes downstream from large reservoirs in Kansas. U.S. Geological Survey Water-Resources Investigations Report 01-4205, 24 p.

Juracek, K.E., 2002, Historical channel change along Soldier Creek, northeast Kansas. U.S. Geological Survey Water-Resources Investigations Report 02-4047, 23 p.

Juracek, K.E., 2003. Sediment deposition and occurrence of selected nutrients, other chemical constituents, and diatoms in bottom sediment, Perry Lake, northeast Kansas, 1969-2001. U.S. Geological Survey Water-Resources Investigations Report 03-4025, 56 p.

Juracek, K.E., 2004a, Historical channel-bed elevation change as a result of multiple disturbances, Soldier Creek, Kansas. Physical Geography, v. 25, n. 4, p. 269-290.

Juracek, K.E., 2004b. Sedimentation and occurrence and trends of selected chemical constituents in bottom sediment of 10 small reservoirs,, eastern Kansas. U.S. Geological Survey Scientific Investigations Report 2004-5228, 80 p.

Juracek, K.E., 2006. Sedimentation and occurrence and trends of selected chemical constituents in bottom sediment, Empire Lake, Cherokee County, Kansas, 1905-2005. U.S. Geological Survey Scientific Investigations Report 2006-5307, 79 p.

Juracek, K.E., and Mau, D.P., 2002. Sediment deposition and occurrence of selected nutrients and other chemical constituents in bottom sediment, Tuttle Creek Lake, northeast Kansas, 1962-1999. U.S. Geological Survey Water-Resources Investigations Report 02-4048, 73 p.

Juracek, K.E., and Ziegler, A.C., 2006. The legacy of leaded gasoline in bottom sediment of small rural reservoirs. Journal of Environmental Quality, v. 35, p. 2092-2102.

Juracek, K.E., and Ziegler, A.C., 2007. Estimation of sediment sources using selected chemical tracers in the Perry Lake and Lake Wabaunsee Basins, northeast Kansas. U.S. Geological Survey Scientific Investigations Report 2007-5020, 53 p.

Lee, Casey J., Rasmussen, Patrick P., and Ziegler, Andrew C., 2008 Characterization of suspended-sediment loading to and from John Redmond Reservoir, east-central Kansas, 2007–2008, U.S. Geological Survey Scientific Investigations Report 2008–5123, 25 p.

Mau, D.P., 2001. Sediment deposition and trends and transport of phosphorus and other chemical constituents, Cheney Reservoir watershed, south-central Kansas. U.S. Geological Survey Water-Resources Investigations Report 01-4085, 40 p.

Morris, G.L., and Fan, J., 1998. Reservoir sedimentation handbook: McGraw-Hill, New York, various pagination.

Pimentel, D., Harvey, C., Resosudarmo, P., Sinclair, K., Kurz, D., McNair, M., Crist, S., Shpritz, L., Fitton, L., Saffouri, R., and Blair, R., 1995. Environmental and economic costs of soil erosion and conservation benefits. Science, v. 267, p. 1117-1123.

Pope, L.M., 2005. Assessment of contaminated streambed sediment in the Kansas part of the historic Tri-State Lead and Zinc Mining District, Cherokee County, 2004. U.S. Geological Survey Scientific Investigations Report 2005-5251, 61 p.

Rasmussen, T.J., Ziegler, A.C., and Rasmussen, P.P., 2005. Estimation of constituent concentrations, densities, loads, and yields in Lower Kansas River, northeast Kansas, using regression models and continuous water-quality monitoring, January 2000 through December 2003. U.S. Geological Survey Scientific Investigations Report 2005-5165, 117 p.

Shields, Jr., F.D., Bowie, A.J., and Cooper, C.M., 1995. Control of streambank erosion due to bed degradation with vegetation and structure. Water Resources Bulletin, v. 31, n. 3, p. 475-489.

Tegtmeier, E.M., and Duffy, M.D., 2004. External costs of agricultural production in the United States. International Journal of Agricultural Sustainability, v. 2, n. 1, p. 1-20.

Van Metre, P.C., Wilson, J.T., Callender, E., and Fuller, C.C., 1998. Similar rates of decrease of persistent, hydrophobic and particle-reactive contaminants in riverine systems: Environmental Science and Technology, v. 32, p. 3312-3317.

Walling, D.E., 2005. Tracing suspended sediment sources in catchments and river systems. Science of the Total Environment, v. 344, p. 159-184.

Zoumis, T., Schmidt, A., Grigorova, L., and Calmano, W., 2001. Contaminants in sediments—remobilisation and demobilization: The Science of the Total Environment, v. 266, p. 195-202.