Florence County Land Conservation Department staff monitor lakes for aquatic invasive species presence/absence, water clarity, dissolved oxygen, pH, conductivity, and temperature.

Aquatic Invasive Species Distribution in Florence County

Statewide Distribution of Aquatic Invasive Species

Aquatic Invasive Species Distribution in the Michigan Upper Peninsula

To view lake maps, clarity and chemistry data, select the town where the boat landing is located:

Town of Aurora

Town of Commonwealth

Town of Fence

Town of Fern

Town of Florence

Town of Homestead

Town of Long Lake

Town of Tipler

What does the data mean?

To learn about how this data relates to fish, see the "Water Quality Parameter Guide for Selected Fish Species" from the UW Extension Citizen Lake Monitoring Network Training Manual.

Fish species distribution in the county.

The following explanations were adapted from the UW Extension Citizen Lake Monitoring Network Training Manual:

Clarity  was determined using a black and white Secchi disk.  Clarity is one factor used to determine the trophic state of a lake and it is dependent on factors such as water color, turbidity, algae, etc.  A single Secchi reading will not tell you a great deal of information, but multiple readings over several years can indicate whether or not lake clarity is changing. 

Dissolved oxygen was determined using a Hach HQ40d multi parameter meter.  The dissolved oxygen probe was inoperable for a short time, so some lakes may not have dissolved oxygen data.  The amount of dissolved oxygen in the water is determined by water temperature (e.g., cold water holds more oxygen than warm water), atmospheric pressure, and biological productivity.  Low dissolved oxygen levels can cause a release of phosphorus and sediments into the water column. In extreme cases, low dissolved oxygen can result in the elimination of the cold-water fishery and other bottom-dwelling animals.

pH was determined using a Hach HQ40d multi parameter meter.  A pH of 7 is neutral, lower values are acid and higher values are alkaline.  A pH of 6.5-8.5 is the normal range; only extreme ranges may cause an adverse effect on the fish population.  It is believed that zebra mussels cannot survive extreme pH ranges. 

Conductivity was determined using a Hach HQ40d multi parameter meter.  Conductivity is expressed in terms of electrical conductance and measures total amount of electrolytes or ionized materials. Conductivity is dependent on geology, watershed size, source of ions (e.g., runoff), evaporation, etc.  Conductivity varies greatly from lake to lake. 

Temperature was determined using a Hach HQ40d multi parameter meter.  The temperature profile data will tell you whether your lake mixes or stratifies.  Typically, shallow lakes mix constantly through normal wind and wave action.  Because of this mixing, temperature and dissolved oxygen values remain about the same from the surface to bottom.  In contrast, deep lakes usually stratify or divide into distinct temperature layers during the summer months. The warm water stays at the top and the cold water stays at the bottom. The zone at which the temperature changes most abruptly is called the thermocline.  Normally, deep lakes stratify during the summer months and mix during the spring and fall.  Summer stratification determines the depths which certain fish species may be found. 

If you have any questions or would like more information,
please contact Maureen at 715-528-5940