How We Monitor

We monitor pH, dissolved oxygen, turbidity, and temperature with equipment purchased from the HACH Company, which has their world headquarters in Loveland, Colorado. The equipment purchased for this project came with a price tag ranging from $600 to $900 each. Over the first three years of the project the commission has invested in 15 meters (five pH meters, five dissolved oxygen meters, and five turbidimeters). The program has also received, by generous donation, six meters (two of each type) from FPL Maine Energy Hydro, Inc., and three meters (one of each type) from The Nature Conservancy. With eight complete meter sets, we have the basics necessary to undertake a project that monitors 27 locations over a four-day period every other week.

pH MeterpH

To monitor pH we use the HACH sensION2 Portable pH/ISE Meter with Platinum Series pH electrode (Catalog #51725-10). This meter has a measurement range of 0 to 14 units. We also record temperature data from this meter with it’s built in thermometer. The temperature range for this meter is -10 to 110° C. These meters must be successfully calibrated by the volunteers each morning prior to testing, and in some cases, the meters are recalibrated when used for multiple testing on the same morning.

Dissolved Oxygen MeterDissolved Oxygen

To monitor dissolved oxygen we use the HACH sensION6 Portable Dissolved Oxygen Meter with 15 meter probe (Catalog #51850-12). This meter has a measurement range of 0 to 20.0 milligrams of oxygen per Liter of water. We record the temperature data from this meter as well. The temperature range for this meter is 0 to 50° C.

TurbidimeterTurbidity

To monitor turbidity we use the 2100P Portable Turbidimeter (Catalog #46500-00). This meter has a measurement range of 0 to 1,000 nephelometric turbidity units (NTUs).

Temperature

ThermometerAlthough we gather temperature information from both our pH and Dissolved Oxygen meters, we have a non-mercury Pocket Thermometer (Catalog #26763-00) as well. The range for this device is -5 to45° C. Our primary temperature readings are taken from the pocket thermometer.

Escherichia coli

Our volunteers gather water samples for the E. coli testing by using a sterile 100 ml container. In order to obtain coliform information our volunteers must obtain a 100 milliliter sample of water, taken at least 6 inches below the surface. These samples are obtained below the surface to ensure that there are no possible contaminates from the surface water that could alter the results. These samples are put on ice for transportation to Katahdin Analytical Services. The holding time for coliform is not to exceed six hours.

Total Kjeldahl Nitrogen

Our volunteers gather a 250 mL water sample for testing at the laboratory. This sample is also transported on ice to the lab. Although holding times for nutrients (on ice) is a few days, these samples are handed over to Katahdin Analytical Services at the same time as the E. coli.

Total Phosphate

Our volunteers gather a 250 mL water sample in a container that has undergone a special acid wash procedure. The reason behind the acid wash is that phosphorus is an extremely sensitive parameter and this will help ensure a clean bottle and an accurate testing result. This sample is transported on ice back to the Commission Office where we add 1 mL of sulfuric acid and then freeze the sample until it is transported to the University of New Hampshire.

Orthophosphate

Our volunteers again gather a 250 mL water sample in a container that is transported on ice back to the Commission Office. Once back in the office, we filter the sample through a special material and pour the water into a bottle that has underdone the same acid wash procedure as the one used for the total phosphate sample. This sample is also frozen until transported to the University of New Hampshire.

Alkalinity

The testing procedures for this parameter is the same as total Kjeldahl nitrogen. The volunteer gathers a separate 250 mL water sample that is transported on ice to Katahdin Analytical Services for testing.