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The City of Springfield is located within the Springfield Plateaus section of the Ozark Plateaus physiographic province in southwest Missouri. Bedrock underlying Springfield and the surrounding area is dominantly limestone and dolostone with well-developed karst features. Springfield is located within Missouri's primary karst area, which is operationally defined as an area containing more than 10 sinkholes per 100 square miles. Sinkholes are so prevalent in the Springfield urbanized area that they are sometimes used as stormwater conduits. These conduits often lead to nearby streams that ultimately route stormwater to the James River.
Springfield's population presently is 150,000 and has grown 1.3 percent over the last 10 years. Impervious areas have increased by 5 percent within this time and contribute a substantial amount of runoff to the local stream network, which includes Wilson Creek and Pearson Creek (click here for map). The surrounding Greene County is expected to have an increase in population of about 65,000 by the year 2020. Based on the expansion in urban areas and the increasing population, streams and rivers receiving stormwater and other non-stormwater discharges are likely to show additional adverse water-quality effects.
Wilson Creek and Pearson Creek are major contributors to the James River water budget. As a result, these streams can contribute a substantial load of contaminants to the James River. Wilson creek, Pearson Creek, and the James River are listed on Missouri's 303 (d) list for development of Total Maximum Daily Loads (TMDLs). Wilson Creek and Pearson Creek are listed as having unknown toxicity with affected reach lengths of 14 and 1.5 miles, respectively. The James River is one of the main water sources for Table Rock Lake and has been implicated as the source of increased nutrient loading to the lake. A 57 mile reach of the James River is considered a high priority site for establishing TMDLs for nutrients and other unknown toxic constituents.
Wilson Creek and its tributaries drain a large part of Springfield and have shown adverse water-quality effects over the last several decades. Harvey and Skelton (1968) described the hydrology of Wilson Creek and its relation to Rader Spring during base flow and stormflow conditions. Results of this study show that discharge from Rader Spring contains a substantial part of effluent from the Southwest Sewage Treatment Plant. This study also notes that seismic testing shows numerous caves and fissures not apparent from topography that can carry and store large quantities of water and contaminants.
Pearson Creek is located on the eastern side of Springfield in an area of growing urbanization. Due to the karst nature of the area, runoff from the commercialized areas to the west is being routed through complex natural conduits to Jones Spring, which becomes a tributary to Pearson Creek. The potential for serious water-quality degradation within this basin was realized in the late 1970's following an intensive hydrologic investigation by the USGS and Missouri Department of Natural Resources. While the sensitivity of this stream has been noted, no studies have been done to assess the quality of Pearson Creek and to determine the nature of the alleged toxicity.
Based on the current status of Wilson Creek and Pearson Creek, the USGS will conduct an intensive water-quality investigation that will focus on organic and trace metal contamination in relation to the alleged toxic conditions of these waters. The data will be used to calculate loads of each contaminant in water that drains to the James River. This study is expected to provide needed information to the regulatory community for implementing sound resource management practices.
Samples will be collected from 6 sites (click for list of sites) and will be analyzed for an extensive list of water quality parameters including major cations and anions, trace metals, nutrients, indicator fecal bacteria, and pesticides (two sites). In addition to these water quality parameters, acute toxicity will be determined using the MICROTOX toxicity testing system. Toxicity tests will be performed on extracts from semi-permeable membrane devices (SPMDs) that will be deployed both long-term (30 days) and during storm events.
Samples from the six sites will be collected during high and low base flow conditions and from four storm events. One storm event will be sampled during each season (spring, summer, fall, winter). Samples will be collected following at least a 72 hour period of no runoff. Ideally, all six sites would be collected during the same storm event; however, rainfall intensities are highly variable even in this small study area around the city of Springfield. As a result, oftentimes only a subset of the six sites will be sampled in any one storm event, but every effort will be made to sample each of the six sites once during each season.
To provide data for the calculation of constituent loads, the USGS located the water-quality data collection sites with stream gages. Prior to the start of this project, three stream gaging stations existed in the Wilson Creek watershed. The USGS constructed three additional gages for the purposes of this project. One was constructed near an old gage site on Wilson Creek and two were constructed in the Pearson Creek watershed.
Contact address:
Joseph M. Richards, Hydrologist
U.S. Geological Survey
1400 Independence Rd, Mail Stop 100
Rolla, MO 65401
PHONE: 573-308-3568
FAX: 573-308-3645
EMAIL:richards@usgs.gov
U.S. Department of the Interior, U.S. Geological Survey
Maintainer: Rita Choate, Webmaster
Updated: January 12, 2005
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URL: http://mo.water.usgs.gov/current_studies/richards/spfd/spfd2.htm
