Why Does NDEE Monitor Streams?
Nebraska’s streams and rivers provide essential resources to the residents of our state. These streams supply irrigation and drinking water, support diverse fish and wildlife communities, offer numerous recreational opportunities, and are integral to the state’s industry and electricity production. However, many of these streams also serve as conveyances to dispose of agricultural, industrial, and municipal wastewater and runoff. Assuring that Nebraska’s streams can safely support these numerous, and at times, conflicting uses is the responsibility of the NDEE.
Regular stream monitoring allows NDEE to determine if water quality conditions meet state and federal standards to safely support the assigned designated uses. If the monitoring data indicate a water quality problem, NDEE uses these data to locate potential pollutant sources and develop point and non-point source pollution control plans. Regular monitoring also allows NDEE to recognize trends in stream water quality that may lead to more efficient and effective pollution controls. Finally, NDEE uses stream monitoring data to generate a portion of the Water Quality Integrated Report to submit to the United States Environmental Protection Agency, as required by the federal Clean Water Act. This report is submitted in April of even numbered years and is used by NDEE as part of the prioritization process for the development of pollution control or watershed management plans.
History of the Ambient Stream Monitoring Program
NDEE has maintained a network of stream monitoring sites since the inception of the agency in 1971. In the early 1970s, 365 sites were monitored on a quarterly basis to gather baseline data on streams where there was limited information. In 1978, the program was reorganized to consist of 90 sites that were monitored monthly. The program was again restructured in 2001 to a network of 97 sites and sampling has been conducted monthly at each of these sites ever since. Additional changes to the ASMP network were made in 2016 when four sites were added to the network, bringing the total number of sites sampled to 101. Approximately 1,212 water quality samples are analyzed annually for the 32 parameters collected for this program
Where and When is the Monitoring Done?
The Ambient Stream Monitoring Program (ASMP) consists of 101 fixed monitoring sites designed to collect data from all 13 of Nebraska’s major river basins. Samples are collected from each site on the first week of each month, year-round with monitoring assistance provided by the US Army Corps of Engineers (USACE) and South Platte and Middle Niobrara NRDs. The map shows the locations of the 101 monitoring sites sampled as part of the Ambient Stream Monitoring network.
How were the Monitoring Sites Selected?
Nebraska’s ASMP was designed to evaluate surface water quality in each of the State’s 13 major river basins. To achieve this goal, the 13 major basins were subdivided by geology, land-use, soil type, and topography. Three types of monitoring sites were then established in each basin: indicator sites, stream integrator sites, and basin integrator sites. Indicator sites are located on streams that drain areas of homogenous land-use, soil type, and geology, and provide background water quality information for the predominant ecoregions of each basin. Stream integrator sites are located at key intersections in the drainage network so that the most significant tributaries or contaminant sources in a basin are sampled by at least one of these sites. Basin integrator sites are located at the bottom of each major basin and provide insight into the water quality of the entire river basin.
What is Monitored?
NDEE monitors numerous water quality parameters to establish general water quality trends and to ensure each stream is able to support its designated uses. The following parameters are collected at each site every month:
• water temperature
• dissolved oxygen
• total suspended solids
• nitrate/nitrite nitrogen
• kjeldahl nitrogen
• total phosphorus
• E. coliIn addition, atrazine samples are collected at all sites from May through September. Arsenic, selenium, calcium, magnesium, and sodium are collected at all sites quarterly, as are a complete suite of metals at each basin integrator site.
More information about all surface water impairments is available in the 2018 Water Quality Integrated Report. This report combines the Clean Water Act 303(d) impaired waters list with the 305(b) summary of the health of Nebraska’s surface waters. This report is available on NDEE’s website at http://dee.ne.gov or directly at http://dee.ne.gov/publica.nsf/pages/WAT234
To contact program experts, call (402) 471-4709 or (402) 471-4264.