2.5.4 Wetlands

Approximately 14 percent of the land area within the Gleason Lake subwatershed is shown on the National Wetland Inventory as wetland. 

Table 6.  National Wetlands Inventory wetlands in the Gleason Lake subwatershed.

Circular 39 Type

Area (acres)

Cowardin Class

Area (acres)

Seasonal

4.1

Emergent

261.1

Wet Meadow

0.5

Forested

17.3

Shallow Marsh

256.5

Scrub Shrub

16.6

Deep Marsh

16.3

Unconsolidated Bottom

243.6

Open Water

227.3

 

 

Scrub Shrub

16.6

 

 

Forested

17.3

 

 

TOTAL

 538.6

 

 538.6

Source: Minnesota DNR.

In 2001-2003 the District undertook a Functional Assessment of Wetlands 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 6 above, which shows wetland acreage and type from the National Wetlands Inventory completed in the 1980s, Table 7 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 8).  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 7.  Dominant wetland type in the Gleason Lake subwatershed as assessed in the Functional Assessment of Wetlands.

Circular 39 Type

Area (acres)

Seasonal

12.3

Wet Meadow

13.4

Shallow Marsh

213.2

Deep Marsh

15.4

Open Water

127.6

Scrub Shrub

9.0

Forested

60.2

Lakes

15.3

Not typed

5.1

TOTAL

 471.5

Note: Based on field assessment.  Excludes those areas determined in the field not to be wetlands, and stormwater ponds clearly excavated out of upland.   Includes some small areas that were not field assessed.

Source: MCWD 2003 Functional Assessment of Wetlands.  See Figure 11.

Table 8.  Wetland management classifications of wetlands in the Gleason Lake subwatershed as determined in the Functional Assessment of Wetlands.

Classification

Number

Area (acres)

% of total

Preserve

33

121.6

25.0

Manage 1

42

132.0

27.2

Manage 2

25

118.8

24.7

Manage 3

72

113.4

23.1

TOTAL

 172

 485.8

 

Note:  The FAW excluded large lakes and wetlands less than ¼ acre in size; those areas are included in the NWI, so total will not match Tables 6 or 7.

Source: MCWD 2003 Functional Assessment of Wetlands.  See Figure 12.

The Gleason Lake subwatershed has a wide scattering of small wetlands across the subwatershed.  Two large wetlands – on the east side of Gleason lake and just south of TH 55 –scored highly on vegetative diversity, fish and wildlife habitat, or aesthetics (see Figure 13).  Other high quality wetlands include those riparian to Gleason Lake.

Some of the wetlands were also evaluated for restoration potential.  Factors considered were the ease with which the wetland could be restored, the number of landowners within the historic basin, the size of the potential restoration area, the potential for establishing buffer areas or water quality ponding, and the extent and type of hydrologic alteration.  Only a few small wetlands of moderate restoration potential are located throughout the subwatershed, and one small wetland with high potential for restoration (see Figure 14).