How does your lake compare?
If you want to compare your lake to lakes across the state or across the nation, you should check out the Lake Comparison Tool from the EPA.
Read on for some help using the Lake Comparison Tool with LMVP data.
The EPA Lake Comparison Tool, with Stockton Lake clarity (Secchi Depth) entered.
To use the tool, you enter the indicator (the data type you want to compare), your lake’s value, the year (you must type something here, I just typed 2024), and select MO from the pulldown list. The Lake Name section is not required. See the picture above for an example.
To find a Missouri lake’s long-term average value, go to the LMVP website’s homepage and click a lake on the map (scroll down to see the map). In the popup window, you’ll see average values for the parameters we measure. Use these numbers in the Lake Comparison Tool and see how any of our lakes are doing compared to Missouri or the USA. See the image below.
Finding Stockton's long-term average clarity at the LMVP website. If you want to find a single year’s average value for a public LMVP lake, you can use our LMVP Data Viewer. You'll need to convert feet to meters for the Lake Comparison Tool.
The Lake Comparison Tool looks at data from the National Lakes Assessment (NLA). This is a project that recurs every 5 years. Our lab has monitored Missouri’s lakes for the NLA since the project began in 2007. You can read about our 2022 experience here. The NLA is a large-scale effort designed to assess the state of the nation’s lakes. EPA uses a probability-based random selection process for each ecological region of the nation to assure that all lakes larger than 2.4 acres (1 hectare) and at least 3.3 feet (1 meter) are represented. Note that the lakes sampled for the LMVP tend to be larger and deeper.
In the example above, Stockton Lake had more water clarity than any Missouri lake sampled for the NLA project. This puts Stockton in the 100th percentile. While other Missouri lakes may have more clarity, they were not sampled for the NLA.
A few things to note:
The Lake Comparison Tool compares your lake to all lakes sampled during a specific NLA year, regardless of lake size or what the watershed holds. The smallest NLA lake sampled in 2022 was 2.5 acres.
For several reasons, water quality varies over time (you can read about it here) and NLA data may not take that into account because most NLA lakes are sampled just once. LMVP lakes are sampled many times each season to try to account for this variability.
Water quality differs at different parts of a lake. NLA lakes are sampled midway between the primary inflow and the dam, while LMVP lakes are typically sampled at the dam.
The results of the 2022 NLA effort are available at the EPA website.