What's New
This area does not yet contain any content.

Great Bend Region Fall 2010 Sample Results

Volunteers sampled 202 stream sites on Friday, September 17th between 3 and 5 p.m.  Results of their efforts are presented below.

Temperature - Samplers measured temperature in the field directly from the stream at the time of sample collection. Temperature is an important parameter as it is the regulator for aquatic communities - all plankton, bug, and fish species have a preferred temperature. Temperature also controls the amount of dissolved oxygen present in the water - cooler temperature waters hold more dissolved oxygen. Finally, temperature controls the rate at which chemical reactions occur, such as the conversion of nitrate-nitrogen to ammonia-nitrogen. Higher temperatures are shown in darker colors. Several factors affect temperature including riparian buffers or shading, watershed inputs, and surrounding land uses. Highest temperatures were measured in small, headwater streams. Temperatures measured during 2010 generally mimic those measured in 2009 with higher temperatures measured in streams where water levels were shallow and/or the water is generally exposed to direct sunlight.

pH - Samplers measured pH from water samples at the staging location. Water pH is a measure of the amount of hydrogen ion available in the water. Water pH determines the solubility and biological availability of chemicals, including nutrients such as nitrogen and phosphorus, and metals, like copper or lead. Typical pH levels in streams measure 6.5 to 8.5. pH levels are indicative of the geological materials in the drainage area. Additionally, the amount of photosynthesis occurring in the stream can affect pH levels. This means that streams where high levels of algae occur result in higher pH levels. Higher pH levels are shown in darker colors, while lower pH levels are displayed in lighter colors. Further observation is necessary in those tributaries where low pH levels were measured. When compared with 2009 levels, 2010 pH levels generally measured higher. This is especially apparent in the western portion of the watershed especially Kickapoo and Little Pine creeks in Warren County. Additional elevated pH levels were observed throughout the northern and southern portions of the watershed in Burnett and Wea creeks. These levels were generally associated with locations where algae blooms were noted during sampling.

Transparency - Samplers measured water transparency using transparency tubes. Water transparency in streams reflects the distance downstream that you can see through the water. Tubes measured 114 centimeters, so any values greater than 114 centimeters exceed our ability to detect a change in water transparency. Low numbers (10 cm) indicate poor transparency, while those in the 70 centimeter (2 foot) range indicate good transparency.

Orthophoshate - Phosphorus is typically the nutrient which limits the productivity in aquatic communities.  Phosphorus can be measured in many forms including orthophosphate or soluble reactive phosphorus. This form of phosphorus is the soluble, organic, readily available form of phosphorus. Higher phosphorus concentrations typically lead to higher levels of productivity. Increased productivity can result in increased concentrations of algae or plants, which can result in decreased dissolved oxygen concentrations, taste and odor problems, and create poor habitat for aquatic communities. Concentrations of orthophosphate measuring higher than 0.05 ppm are of concern. These subwatersheds will be further reviewed to identify potential nutrient sources in these locations.

Nitrate/Nitrite - Nitrate-nitrogen and nitrite-nitrogen, like orthophosphate, represent the available nitrogen in an aquatic system. Nitrogen is also available in the atmosphere and can move from the air into the water by nitrogen-fixers. Nitrogen can readily convert between different forms, especially nitrate and nitrite. Conversion to and from ammonia also occurs when dissolved oxygen is available in the system. Nitrate and nitrite concentrations are displayed below with darker colors representing higher concentrations. Nitrate-nitrogen concentrations measuring higher than 2 ppm can inhibit aquatic communities. Concentrations higher than 10 ppm violate the state water quality standards. Nitrate-nitrogen concentrations mimic those found during the Fall 2009 sampling blitz. Generally, sites which exhibited high nitrate-nitrogen concentrations in 2009 also exhibited high nitrate-nitrogen concentrations in 2010.

Alkalinity - Samplers measured alkalinity from water samples at the staging location. Alkalinity and hardness also reflect the geological materials present in the drainage area. Alkalinity is a measurement of the base concentration in water. Nitrates, dissolved ammonia, orthophosphate, silicate, and hydroxides all generate higher alkalinity concentrations. As with pH, darker colors indicate higher alkalinity concentrations, while lighter colors reflect lower alkalinity concentrations.

Hardness - Samplers measured hardness from water samples at the staging location. Hardness is a measure of the mineral content including calcium and magnesium present in surface water. Hardness measurements less than 200 represent slightly hard water, while hardness measuring higher than 720 is considered hard water. Like alkalinity measurements, the predominance of dark subwatersheds suggests that the test strips did not contain a high enough detection level to correctly measure hardness in our watershed.

E. coli - E. coli is an indicator organism used to monitor pathogen concentrations with surface waters. E. coli is present in the intestines of all warm-blooded mammals and can survive and reproduce outside of the body. Untreated sewage, combined sewer overflows, polluted discharges, input from animals, and source populations can all contribute E. coli to surface waters. In Indiana, concentrations measuring greater than 235 colonies/100 mL are deemed non-supporting of their designated use. In the figure below, those watersheds which do not meet water quality standards are shown in darker colors.

Back to Blitz