2.5.4 Wetlands

Approximately 18 percent of the land area within the Schutz Lake subwatershed is shown on the National Wetland Inventory as wetland (see Table 5).

Table 5.  National Wetlands Inventory wetlands in the Schutz Lake subwatershed.

Circular 39 TypeArea (acres)Cowardin ClassArea (acres)
Seasonal2.3Emergent59.4
Shallow Marsh57.0Forested0.9
Deep Marsh5.0Unconsolidated Bottom109.7
Open Water104.7  
Forested0.9  
Total169.9 169.9

Source: Minnesota DNR

In 2001-2003 the District undertook a Functional Assessment of Wetlands (FAW) on all wetlands greater than one-quarter acre in size. This assessment used a variant of the Minnesota Routine Assessment Method. In contrast to Table 5 above, which shows wetland acreage and type from the National Wetlands Inventory completed in the 1980s, Table 6 below shows the acreage and type as assessed in the field. Using the results of that analysis, individual wetlands were assigned to one of four categories – Preserve, and Manage 1, 2, or 3 (see Figure 12 and Table 7). Wetlands that were evaluated as Exceptional or High on certain ecological or hydrologic values were assigned to the Preserve category. The balance of evaluated wetlands were assigned to a category based on this assessment of current functions and values, with Manage 1 wetlands exhibiting higher values and Manage 2 and 3 moderate or lower values. Refer to the Functional Assessment of Wetlands (2003) for details of methodology, classification, and management recommendations.

Table 6.  Dominant wetland type in the Schutz Lake subwatershed as assessed in the Funtional Assessment of Wetlands.

Circular 39 TypeArea (acres)
Seasonal5.1
Wet Meadow54.8
Shallow Marsh14.4
Deep Marsh36.4
Open Water3.2
Scrub Shrub0.3
Forested13.9
Lakes106.0
Not Typed4.3
Total238.4

Note: The FAW excluded large lakes and wetlands less than 1/4 acre in size; those areas are included in the NWI, so total will not match Tables 5 or 6.

Source: Minnesota DNR.  See Figure 12.

The Preserve wetlands within the Schutz Lake subwatershed were classified as such because of their landscape location and their ability to provide downstream water quality protection (see Figure 12).

There are numerous wetlands in the subwatershed that the FAW identified as being of high or moderate restoration potential (see Figure 14). Several wetlands along the central drainage corridor were identified as high restoration potential, along with some wetlands on Arboretum property.