Water Quality Monitoring

Several years ago the number-one question we received was, “How is the quality of the water?” To answer that question, we relied on the knowledge that Class A and AA waters stretch over vast segments of the rivers within the corridor and also that the rivers have a relatively natural and unspoiled look. But, there was something missing. Did we actually know the quality of the water? Were we really striving towards our agency mission to “protect public health, safety and quality of life…” by not first obtaining scientific data before answering the question being asked? The decision was made, and when the budget caught up, the Saco River Basin Water Quality Monitoring Program officially began in 2001.

The data was now being gathered with the intention that after a few years we would be able to answer this common question regarding water quality with actual data to back it up. However, there surfaced another question: “Why start a water quality monitoring program?” What was once, in our minds, the obvious answer to that question is now not so apparent.

What exactly are we trying to accomplish with this program? We have eight years of data now. Is that enough? Is it really necessary to continue monitoring when the results don’t drastically change from year to year? The simple answer, although never obvious, is yes, sampling for quality is an on-going process. Rivers are in a constant state of change. Without continued monitoring you have essentially taken a snap shot of one moment in time. While a photo can speak a thousand words, a living documentary can reveal volumes.

A sustainable water quality monitoring program is based on five important steps:

  1. Generally characterize water quality.
  2. Understand general condition of water.
  3. Determine if degraded water quality exists.
  4. Decide if a further study is needed to diagnose and possibly solve problems.
  5. Continue and broaden understanding of water quality.

It takes time to effectively progress through each of these levels. Take the first two steps as an example. In order to characterize and understand the general condition of the water with any certainty, you would first need to look at no less than three to five years of baseline data. In looking at this raw data you would be searching for trend patterns which may reveal consistent problem areas. These types of patterns may or may not be discovered, or even exist in the three to five year time frame. If the baseline data doesn’t show any patterns then a longer time frame of data collection is needed.

Once it is determined that there are well defined patterns, and those same patterns have been studied to create a representation of what water quality exists, you can take another step.

The next level is entirely based on the patterns observed. If there were “problem areas” noted then you would proceed to step 4 and further monitor the trouble spots to determine what the source is, if any, of the pollution. If there was no degradation noted, you would jump to step five.

The fifth step — the most important step for future protection of the rivers — is to continue with the program. That is the only way to maintain a working knowledge of the water and the land uses surrounding our rivers.