Equipment

There have been changes in the equipment Citizen Lake Monitors have used. This page will give you detailed information on each sampling device. Volunteers have been collecting chlorophyll, phosphorus, temperature, and dissolved oxygen on their lakes since 1990. These parameters are necessary to determine a Trophic State Index value for their lake. The sampling takes an average of about 3-4 hours and involves not only on-lake procedures, but also taking samples back home for processing and mailing the phosphorus and chlorophyll samples to the State Lab of Hygiene in Madison. We thank the volunteers that have dedicated their time to take these water samples!

We can thank one of our regular Secchi disc volunteers for the ingenious "Wisconsin Self-Help Monitoring Water Sampler." Paul Anderson, native to Madison, is the inventor of the Mason Jar. Click on the picture of the Mason jar for a more detailed picture.

The water is collected with a simple device - an ordinary Mason jar - with a few adjustments. The jar is filled part way with cement to make it heavy. The lid is equipped with two tubes - one to let water in and one to let air out. The tubes are stoppered and with the lid screwed on, the jar is lowered to whatever depth is necessary. At that point, the volunteer pulls on the stopper cord and "pulls the plugs," allowing that water to go in one tube and the air that was in the jar is forced out. When you are sitting in the boat, all you see are air bubbles rising to the surface. When the bubbles stop, you know that jar is full!

When the full Mason jar is hauled to the surface holding water from a specific depth, the work begins. Volunteers begin the test to determine how much dissolved oxygen is in the water.

Two phosphorus samples are also collected: one 1 foot below the top of the lake and one 1 foot above the bottom of the lake. In most lakes, phosphorus eventually sinks to the bottom of the lake and accumulates in the sediment. Thus, we expect that there will be more phosphorus at the lower depths. If there is no oxygen in the bottom waters, the phosphorus may leak out of the mud and be pushed up into the water column. Algae blooms may result.

Finally, some volunteers monitor chlorophyll. Chlorophyll is a pigment found in all green plants, and is responsible for the green color. We are interested in monitoring chlorophyll in the lake because it is an indication of how much algae is present.

Van Dorn Sampler

The Mason jar was easy to use, but it leaked water. To ensure good samples, (Self-Help) Citizen Lake Monitoring decided to go with a standard-type sampler in 1992.

A variety of Van Dorn samplers have been used throughout the history of the Citizen Lake Monitoring Network. Through the years samplers have been modified, but the method of using each type is the same. Currently there are four different Van Dorn samplers that the volunteers use. Volunteers use either a messenger-release or tug-release water sampler to collect the samples. The sampler is basically a clear plastic tube with rubber stoppers at each end. The bottle is prepared for sampling by pulling the looped ends up and over the release pins and clasp them together to hold the stoppers open.

The sampler is lowered to the appropriate depth, as indicated by a red and black mark on the rope. With the stoppers open the water will enter the plastic tube. Once the sampler is at the appropriate depth, the brass messenger is dropped down the line to snap the sampler closed with the water sample inside. If the sampler is a tug-release sampler the volunteer tugs the rope and the sampler closes with the water sample inside.

The water sample is then ready for testing. Volunteers will test dissolved oxygen using either the LaMotte Dissolved Oxygen kit or the CHEMets Dissolved Oxygen kit. The volunteers will also prepare the phosphorus and chlorophyll samples to mail them to the State Lab of Hygiene for analysis.

The integrated sampler is a white PVC pipe (collection tub) with a PVC ball that acts as a water locking mechanism. The ball fits into the "collection end" of the integrated sampler and fits into a male reducing adaptor on the end of the IS. The sampler is slowly lowered vertically into the water, to the 6ft depth, as indicated by a red mark on the pole. The ball has a specific gravity (weight) so that when you lower the IS into the lake, the ball rises into the tube. There is a pin so that the ball can only go so far up into the tube. When you pull the IS back into the boat, the weight of the water in the IS pushes the ball back into the adaptor, sealing the water into the tube. There is 970 mls of water contained in the sampler that is ready to be tested.

Now that the water is in the juice jug, it is ready for testing. Volunteers will test dissolved oxygen using either the LaMotte Dissolved Oxygen kit or the CHEMets Dissolved Oxygen kit. The volunteers will also prepare the phosphorus and chlorophyll samples to mail them to the State Lab of Hygiene for analysis.