Frequently Asked Questions

Equipment
Submitting Data
Lake Data
Getting Involved
Remote Sensing

Equipment

Where do I get new equipment if my equipment is broken?
Contact your region coordinator and they will help you get new equipment.

What if I did not receive my equipment??
If you did not receive sampling equipment or supplies contact your region coordinator.

Submitting Data

I'm having problems with the Secchi Line. Are there other ways I can enter my data into the system besides the Secchi Line?
You can enter your data online. Here are instructions for how to get started.

Do I mail in the data sheet after every day I monitor?
No, instead use the data sheet until there are no more lines left on the sheet for that particular lake. Each lake and each site should be entered on separate data sheets. If you entered your data online, you don't need to mail in a paper copy. If you phoned in your data on the Secchi Line, be sure to mail a paper copy of your datasheet by November 1.

Should I take readings more than once a month to make data better?
You may monitor Secchi clarity more often than every other week. Volunteer Mary Jane Bumby writes that she enjoys "stalking" for impacts of non-point source pollution on Big Green Lake. She also observes that sever impacts can disappear after only one day, so frequent checks might be important if you have a special need for this type of documentation. Temperature and dissolved oxygen profiles tend to be much more stable than clarity, but you can read these more often than five times per year if you desire. On the other hand, please mail chlorophyll and total phosphorus samples to the lab no more than four and five times respectively per year for analysis. Thanks!

Lake Data

I forgot to send in my data sheets and reports were already sent?
Send Central Office your data sheets in the return envelopes that we provided for you. We will enter the data and then send you an updated report.

There is a mistake in my data.
Contact Central Office-Madison and we will correct the mistake for you and then send you a new report.

What are the minimum D.O. levels at which different fish species can survive?
As D.O. levels drop, stress is put on the fish to find oxygen from anywhere. This point for warm-water fish (like largemouth bass or bluegill) is 5.0 mg/L and for cold-water fish (like trout and salmon) is 6.0 mg/L. Remember that cold water holds more oxygen than warm water. If the D.O. drops down near 2 mg/L for a few hours, large fish kills likely will result.

Why do we take Total Phosphorous and Chlorophyll samples at certain depths?
At 3-feet deep (with a Van Dorn) or 0-6 feet (with an Integrated Sampler), the sampler will be in the epilimnion (top layer) of the lake, so it should give a good representation of how much is being mixed throughout the entire epilimnion. We wouldn't want to sample at the surface because chlorophyll and phosphorus would be greater there than at the bottom of the epilimnion.

What if my TSI for Secchi, TP, and Chl are quite different? What does this mean?
Lakes tend to vary quite a bit, even from day to day. So, if you were to take a reading following a large rainstorm, you may notice a low Secchi reading due to suspended solids (giving the water a murky, brown color), but the chlorophyll and phosphorus readings will remain the same. This is because there hasn't been enough time for changes to occur within the lake. Also, if your lake has a lot of plants, it could skew the TSI values slightly. The main thing to remember is that the TSI is not definitive; it is designed to give you an idea of the type of lake you sample on.

How do I know if there is a trend in the data on my lake?
If there seems to be a rise of fall on your TSI or Secchi graphs with the data points over time, it may indicate some type of trend is going on in your lake. However, remember that lakes naturally vary from year to year depending on many different conditions, so don't be alarmed if suddenly your Secchi average is much lower one year than the previous.

How do I get another annual report for my lake or for other lakes?
You can contact Central Office-Madison and request an annual report, TSI graph, or Secchi graph for any lake we have data for, including another report from your own lake. Also, now you can use the Lake Water Quality Data page to access reports online.

On my annual report, a lab comment for a chlorophyll sample said "Chl holding time exceeded by 14 days." What are the implications for my data? What does the comment mean?
The comment is immaterial to how you interpret or use your data. It means the state lab received more samples than they could process within the recommended holding time for the sample. Here?s what happens: The lab receives your sample. If the ice is melted, they measure and record the temperature of the contents. They put the chlorophyll sample in the freezer and refrigerate the phosphorus bottle. If they can?t process the sample within 28 days, the recommended holding time, they note the number of additional days until they could process it. During this time, the sample IS frozen, so very little degradation occurs. The note just means a small amount of accuracy may have been lost due to the delay. This potential loss of accuracy is inconsequential, but for quality assurance purposes, it still needs to be noted on your annual report.

Why does the Secchi disc value increase after a rainstorm?
Logically, one would think that a rainstorm would add mud or debris to a lake and make the water more murky. Sometimes this is true and the water clarity will decrease. But sometimes just the opposite happens. Algae thrive in warm, calm water, and the Secchi disc value will be low. A rainsotrm may lower the water temperature. Because algae don't survive as well under cooler conditions, they die off. Associated winds may also mix the algae that were congregated near the surface down into the water column. Both factors will result in improved water clarity. Weather observations can be critical to interpreting the Secchi disc and staff gauge data. If possible, use a rain gauge to record the amount of rainfall between readings or read the local paper for this information.

Is my Lake Susceptible to Acid Rain?
The alkalinity of a lake is a measure of its ability to buffer acid rain and snow. The DNR has pH and alkalinity measurements for most of the lakes in the state and can categorize which lakes are sensitive to acid rain and which are not. While much of the precipitation that falls on the state is acidic (pH between 4.4 and 4.7), the majority of lakes in the state are not sensitive to acid rain and snow beacuse of their high alkalinities or ability to buffer the precipitation.

How Do you Judge Water Color?
The best way to measure water color is to use the Secchi disc as a background. If your Secchi disc reading is low (1.5-6 feet), lower the disc about two inches below the water surface; if the Secchi disc reading is greater than 6 feet, lower the disc about two feet into the water. Compare the color of the water to the white color of the disc. Then ask yourself the question: Does the white color of the disc still appear white, meaning the water is clear, does it appear green, or is it brown? Circle the appropriate color on the post card and on your data form. Many of you are reporting changes in water color as the season has progressed. Summer algae blooms may have shifted the water color from clear to green. As algae die off, the water may again be clear. A heavy rainfall and associated mud washing into the lake may change the water color to brown. Water color and changes in water color may be one indicator of water quality. Remember though that some lakes are naturally "stained" lakes, with tea-colored water which does not reflect poor water quality. Many of you can expect to see further changes in water color as the weather cools off, water temperatures start to drop, and as many lakes "turnover" in the fall. Remember to use the Secchi disc to judge the color.

Why do we measure clarity out in the middle of the lake, in the "deep hole" where the water is usually clearer and conditions are quite different than most swimming areas?
Secchi clarity monitoring is intended to give a general picture of the lake's overall health. Algae flourish in warm, calm water, or can accumulate into dense blooms. Similarly, sediment flowing into a lake may not have a uniform distribution. Just as you measure your core body temperature when you are feverish, the best indicator of the lake health is measured in the central or deepest location of a lake. If you notice near-shore water quality conditions are markedly different than your Secchi monitoring site, feel free to add this observation to your data record, making sure to indicate the observation is from the near-shore area.

Getting Involved

How do I join Wisconsin's Citizen Lake Monitoring Network?
Contact your region coordinator and they will train you and supply you with equipment.

Can I start taking Chemistry on my lake?
Contact your region coordinator and they let you know if we have funds available. You can also apply for a Lakes Grant. For more information on grants visit the Lake Grant website

How do I start a Lake Organization?
For more information on starting a lake organization visit the UW-Extension Website (exit DNR) or contact: Lake Specialist UW Extension, College of Natural Resources UW-Steven's Point Steven's Point WI 54881-3897 Many lakes already have organizations in place that deal with issues or concerns about a certain lake or group of lakes. You can attend a local lake organization meeting and present your Annual report.

What other organizations and programs can I join to help improve my lake?
Other organizations include watch programs that watch for different animal or plant species in and around a lake. There are many volunteer opportunities within the DNR; you can monitor aquatic plants, zebra mussels, purple loosestrife, and eurasian water milfoil. You can also become an Island Watch volunteer or be Lake Facilitator. If you are interested in volunteering Contact your region coordinator. You can also join LoonWatch promoting preservation, understanding, and enjoyment of common loons and their aquatic habitats in the Lake Superior region. For more information visit the LoonWatch website or contact: Sigurd Olson Environmental Institute Northland College Ashland, WI 54806-3999 (715) 682-1220 There are many monitoring opportunities for Youth. Interested youth groups, school groups, teachers, and other adult leaders can apply to monitor a lake in their community by visiting the Adopt-A-Lake website or contacting the Adopt-A-Lake Coordinator at (715) 346-3366.

How do I apply for a lake grant?
The best thing to do is to look at the Lake Grant website and check out the guidelines and application process.

Can I send in an article for Lake Tides?
The best way to submit an article is to send it to the WDNR Central Office in Madison. If you have any questions about Lakes Tides you can contact Jennifer Filbert. You can now see the Lake Tides Articles on-line.

What can be done about the weeds on my lake?
Weeds are bad in many parts of the state. The remedy will vary from lake to lake. First, all lake weeds are not bad, and most provide valuable food and habitat for wildlife. However, where excessive or undesirable plant growth prevents you from enjoying your lake, action can be taken. The main alternatives are harvesting by hand or machine, fiberglass screening materials laid on top of the plants, or chemical application. An overall lake management plan should be prepared before choosing the best alternatives(s) for your lake. To remove plants near your pier, you may want to use a rake or pull up the plants by hand. A good place to dispose of the plants is your garden. Our volunteer Ed Holbach on Lake Monona in Dane County can testify to the wonderful mulch lake weeds make! Harvesting by machine requires an investment of money and time, but much more surace water acreage can be covered. Fiberglass screening can be laid on top of the weed beds in the early spring before the plants start to grow, blocking light penetration. Chemicals can be used as a last alternative, but only with a permit from the DNR, and supervision during the actual spraying.

What is my data used for?
Most of the data is used by those who do the sampling, so they get a feel of how their lake cycles every year. Some data has been used in published reports by limnologists and water resource planners. See our complete list of examples.

What if my lake group wants to test the lake for bacteria or other tests not done through the Citizen Lake Monitoring Network?
The State Lab of Hygiene offers environmental testing for bacteria. See the Environmental Health Division webpage for prices and details. The Environmental Task Force Lab also offers additional lake tests beyond the normal Citizen Lake Monitoring Network tests (chlorophyll and phosphorus). Another option is to apply for a Lake Grant to do other tests. The best first step is to talk to your Region Coordinator.

Remote Sensing

What is the Remote Sensing Study about?
It is attempting to use a satellite to predict the trophic state of lakes using observations from space and data from the ground at a lake. For more information go the Remote Sensing page or the Satellite Lake Observatory Initiative (Exit DNR).

What remote sensing path am I in?
Your path will be listed at Remote Sensing on our website. If your path number is not there contact Central Office-Madison.

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