Why Does NDEQ Monitor Streams?
Monitoring streams helps NDEQ determine what the current water quality is, as well as answer questions about whether the water is safe for people and/or livestock to consume, for recreation, for consumption of fish, , drinking, and for industrial or agricultural uses. This monitoring also helps NDEQ make assessments that are used for implementing watershed improvement programs, and to prepare the Integrated Report to the United States Environmental Protection Agency, as required by the federal Clean Water Act (sections 303(d) and 305(b)). NDEQ can also uses the information to assess how effective its programs are in improving water quality.
Where and When is the Monitoring Done?
Monitoring is done at 97 fixed locations across the state on a monthly basis. The map below shows the locations of the monitoring stations.
How are the Monitoring Sites Chosen?
Some of the monitoring sites are chosen to represent the water quality of basins with complex combinations of potential sources of pollution. Other sites are at the outlets of basins where conditions are fairly uniform, while still others monitor streams with the most strict water quality standards for aquatic life.
What is Monitored?
NDEQ monitors for several different water quality parameters to be able to assess stream water quality. Monthly samples are collected at all sites for ammonia, chloride, nitrate-nitrite, total nitrogen, total phosphorus, and total suspended solids. Quarterly samples for selenium and arsenic are collected at all sites, and for various other metals at sites representing watersheds with a complex mix of pollution sources for various metals. Spring/summer samples for herbicides are collected at all sites.
History of the Ambient Stream Monitoring Program
NDEQ has maintained a network of stream monitoring sites since the agency began its work in 1971. In the early 1970’s, 365 sites were monitored on a quarterly basis to gather information on these streams where there had previously been little to none. The number of sites was reduced to 290 in 1975, which is also when monthly monitoring beganbut were monitored monthly rather than quarterly. Several more reductions in the size of the network occurred in the years since, mainly because of budget constraints. In 2008, 97 stream segments were sampling was done on 97 stream segments across sampled across the state, with a total of 2,326 samples being collected.
Impairments and Sources
The most common impairment to Nebraska’s stream quality is fecal bacteria. Potential sources of these bacteria are livestock/feedlot and stormwater runoff and improperly functioning septic tanks. Though not as common an impairment as fecal bacteria, atrazine is also a contributor to degraded stream quality in Nebraska. The source of atrazine is runoff from cropland.
For more information on the quality of Nebraska’s streams, call (402) 471-4249, or refer to the Surface Water Integrated Report at: http://deq.ne.gov/NDEQProg.nsf/OnWeb/TMDL