What is a parameter?
A parameter is something you can measure scientifically. Certain parameters give a concrete idea of how well a river, lake or swim beach can support fish and other wildlife, and how safe or suitable they may be for human uses like swimming, boating or fishing. A few examples of water quality parameters are temperature, acidity (pH), dissolved oxygen levels, and bacteria levels.

Don't we already know our river and streams parameters?
Water quality parameters change constantly. For many rivers and lakes, the only source of scientific data is volunteer monitoring organizations like PRW.

How do these numbers translate into something meaningful?
There are many resources on the internet to help you interpret water quality data. The EPA is one example:

• Dissolved Oxygen (DO)
• Fecal bacterial indicators such as E. coli
• Other parameters such as pH, temperature, phosphorus, nitrates, total solids, conductivity, turbidity and total alkalinity