We sample water to gauge its quality. We look at the chemistry to see if pollutants are present. We look at the underwater invertebrate life to judge water quality by what is able to live in it.
This section presents results of our chemical and biological assessment. We colour-code the results for ease of reading, and we are guided by the criteria used by the EPA in describing levels of water quality. The colours used are:
Bad:
Red
Poor:
Orange
Moderate:
Yellow
Good:
Green
High:
Blue
For biological indicators we use a three-part traffic light code:
Good:
Green
Moderate:
Amber
Poor:
Red
For some indicators we colour code only where safe levels are exceeded, then we code Red.
Score +5 to +9: Good - Green
Score -4 to +4: Moderate - Orange
Score -9 to -5: Poor - Red
Less than 6 mg/L:
Poor - Red
Greater than 0.04 mg/L:
Poor - Red
Greater than 0.01 mg/L:
Poor - Red
Less than 4 mg/L: High - Blue
Equals or greater than 4, less than 8 mg/L: Good - Green
Equals or greater than 8, Less than 18 mg/L: Moderate - Yellow
Equals or greater than 18, less than 25 mg/L: Poor - Orange
25 mg/L or higher: Bad - Red
P less than 0.025 mg/L: High - Blue
P equals or greater than 0.025 and less than 0.035 mg/L: Good - Green
P equals or greater than 0.035 and less than 0.05mg/L: Moderate - Yellow
P equals or greater than 0.05 and less than 0.1mg/L: Poor - Orange
P equals or greater than 0.1mg/L: Bad - Red



Our chemical reference levels for Nitrate NO3 and Phosphorus P correspond to the reporting conventions used in the EPA document Water Quality in 2022: An Indicators Report.
Our biological sampling system, the Citizen Science Stream Index (CSSI) is described at: https://lawaters.ie/citizen-science/
The development and validation of the CSSI is reported at: https://cora.ucc.ie/server/api/core/bitstreams/63d54b7f-9965-43d0-8e30-3b67c6bb1010/content
The levels where we flag Red for dissolved Oxygen, Ammonia NH4 and Nitrite NO2 derive from a directive 2006/44/EC from the EU Parliament and Council, 6 Sept 2006 on the quality of water to support salmonid life.