In the summer of 2013, the Merrimack River Watershed Council partnered with Groundwork Lawrence on an EPA Urban Waters grant to revitalize the Spicket River. Urban waterways can easily become polluted with sewage and runoff so we were monitoring the Spicket River to ensure safety standards are met. Groundwork Lawrence provided data for the Spicket River using a YSI probe device. They tested early in the morning while the water is still cool and the DO is at its lowest. The results below are from their first months of testing. For more information about what Groundwork Lawrence is doing to improve the surrounding community go to their website at groundworklawrence.org.
“Conductivity is a measure of the ability of water to pass an electrical current”. Conductivity can be affected by temperature because warmer water carries a higher conductivity. Discharge and runoff to streams can change the conductivity. The conductivity of rivers in the United States ranges from 50 to 1500 µmhos/cm. Streams supporting good mixed fisheries have a range between 150 and 500 µhos/cm. Higher or lower conductivity could indicate that the water is not suitable for certain aquatic species. Significant changes in conductivity could indicate runoff or some other source of pollution.
Dissolved Oxygen (DO):
Dissolved oxygen (DO) is oxygen that is dissolved in water. Water systems both produce and consume oxygen. Oxygen is gained from the atmosphere and plant photosynthesis and is lost by respiration of aquatic animals, decomposition, and oxygen consuming chemical reactions. If more oxygen is consumed than is produced, the DO levels will decline which will have adverse effects on sensitive animals. Dissolved oxygen is an indicator for good fish health.
pH is a term is used to indicate how basic or acidic a solution is ranked on a scale of 0 to 14, with pH 7 being neutral. pH is an important factor that can limit the distribution of species in aquatic habitats. Different species thrive in different ranges of pH, but most aquatic organisms can withstand a range between pH 6.5-8. pH outside this range causes stresses in many species and can result in decreased reproduction, decreased growth, disease, or death.
Temperature can alter water density and the solubility of oxygen and other chemicals. Fluctuating temperatures and extreme temperatures could be stressful to aquatic life.
Total Dissolved Solids is the concentration of organic and inorganic materials dissolved in water. These substances can be from runoff or pollution discharge.
The amount of light transmission due to absorption and scattering as affected by suspended sediments.
There are many common forms of nitrogen in aquatic ecosystems. The most important in terms of nutrient impairment is nitrate because of its abundance and mobility on land and water.
Of the total phosphorus in aquatic systems, about 25% is considered to be biologically available. The organic and inorganic forms of phosphorus vary significantly in their reactivity and availability for biological productivity.
Dissolved inorganic phosphorus and organic phosphorus. Ortho-phosphates are the most biologically available form of phosphorus, but only counts for a small percentage of less than 10% of the total phosphorus in aquatic systems.
Definitions from EPA.gov