As valued and well used as Prior Lake and Spring Lake are, there is still much mystery below the surface. Where are certain plant species growing, and why there? Have invasive species treatments been effective?  How does plant growth affect lake clarity? To address these questions, the Prior Lake-Spring Lake Watershed District (PLSLWD) is taking action.

In 2013, the PLSLWD started using a program called BioBase, an Automated Vegetation Mapping program, to determine how lake vegetation is changing over time. BioBase uses sonar to detect a lake’s depth, bottom hardness, and vegetation density. With this information, the PLSLWD can make many comparisons which will help influence management decisions within the district.

To begin with, baseline conditions must be documented. Data is collected for the BioBase program by staff and volunteers who take readings with the sonar equipment. This raw sonar data is then processed and maps are created to illustrate conditions. Once the baseline maps have been established, information can be compared across one season or many years. With enough data, the District can determine if there has been a significant permanent change in vegetation, or if a seasonal fluke in the weather is altering water quality. Nature does not follow strict lines, but it does have patterns we can track. Because the District can detect these patterns with the BioBase program, it can identify trouble spots caused by invasive forces or human interference. View Full Article →