Nutrient monitoring volunteers gather water quality samples once a month from May through October. Volunteers most often collect samples for total phosphorus, but sometimes collect samples for nitrogen and total suspended solids as well. Sites for nutrient monitoring are often special projects areas such as regions with TMDL or 9 Key Element Plans.
Volunteers must be engaged in a local coordinator or DNR-led project, and must have one year of baseline data collection completed in order to begin nutrient monitoring. To express interest in nutrient monitoring, please contact your local WAV Coordinator.
What We Monitor
Phosphorus is the most visible, widespread water pollutant in Wisconsin. High levels of phosphorus can trigger excess algae and plant growth in lakes and streams. When these excess plants die and decompose, oxygen levels drop dramatically and can lead to fish kills.
Streams act like conveyor belts, delivering phosphorus directly to lakes. Additionally, phosphorus is associated with excess sediments covering stream bottoms, the most common biological impairment in streams. Phosphorus in streams and lakes originates naturally from rocks, but its major sources today are usually associated with human activities: soil erosion, human and animal wastes, septic systems, detergents and runoff from farmland or lawns.
Phosphorus testing
An analysis of phosphorus often includes both total phosphorus and soluble reactive phosphorus. Volunteers will sample for total phosphorus, which is considered a better indicator of nutrient status because its levels remain more stable than soluble reactive phosphorus. Total phosphorus includes particulate phosphorus—which is attached to bottom sediments and contained in plant and animal fragments suspended in water—and soluble phosphorus. Soluble reactive phosphorus dissolves in water and readily aids plant growth, but its concentration varies widely over short time periods as plants take it up and release it.
At times, monitoring sites will be selected for additional nutrient parameters including total suspended solids and nitrogen.
The goal of this monitoring is to characterize the total phosphorus concentrations most commonly occurring in the streams during the primary algae and aquatic plant “growing season” of May through October.