Laserfiche WebLink
<br />Hydrology: The sample point also did not meet any wetland hydrology indicators. The soil had <br />no saturated layer despite the restrictive layer and the heavy rainfall. <br />Wetland Point <br />The sample point was located approximately 6 feet beyond the toe of slope at the edge of a small <br />hummock in the basin. Shallow surface water was present 6 inches from the sample location. <br /> Vegetation: The dominant species (green ash, Salix amygdaloides / peach-leaf willow, Rhamnus <br />cathartica / common buckthorn, Phalaris arundinacea / reed canary grass, and Vitis riparia / river bank <br />grape) were all FAC or FACW, so the location passed both the Dominance test and Prevalence index for <br />hydrophytic vegetation. The dominant vegetation also passed the FAC-neutral test for wetland <br />hydrology. <br /> Soils: The top 6 inches of the soil profile was a very dark grayish brown loamy sand. The soil <br />from 6-16 inches was a very dark gray mucky peat with sand. The remainder of the boring to 23 inches <br />depth was a dark gray sand with some peat. The boring terminated at 23 inches, because the soil was <br />too saturated to get a cohesive sample below that point. The location met the S3. 5 cm Mucky peat <br />indicator for Problematic Hydric Soils. It is plausible that the loamy sand surface layer was deposited by <br />run-off; the location may have previously met the A3. Black Histic hydric soil indicator. <br /> Hydrology: The location met the primary hydrology indicators A2. High Water Table (water at 4 <br />inches below grade) and A3. Saturation (surface saturation). <br />Discussion <br />The transect data confirmed the presence of a Deep Marsh / Open Water wetland adjacent to the <br />tennis court area. The wetland type at the wetland transect point is Shallow Marsh. The elevated area <br />surrounding the tennis court is mostly filled in wetland, which took place before the adoption of the <br />Wetland Conservation Act. The wetland edge was marked approximately 12 inches above the toe of <br />slope along the northern and eastern sides of the tennis court. The delineation boundary running west <br />along the park and turning north was marked in the low area based on saturation below 12 inches <br />depth. The surface layer of soil was typically darker within the wetland boundary in this area. The <br />wetland has encroached westerly along the southern edge of the tennis court and may extend beyond <br />the historical wetland footprint. Depth of saturation and soil coloration determined the wetland <br />boundary in this area. <br />The wetland basin maintained a wet footprint in all the historical aerial photos, beginning as a drained <br />field in 1940, and becoming progressively wetter over the years. The drainage ditches were blocked and <br />surrounding development probably increased stormwater runoff. It is reasonable to assume that the <br />wetland areas north and east of the park would qualify as WCA Jurisdictional wetland. The status of the <br />area along the southern edge of the tennis court is debatable. The wetland has a direct connection to <br />Lake Johanna via twin culverts, so it will likely be subject to an Army Corps of Engineers section 404 <br />permit. <br /> <br /> <br />City of Arden Hills - Johanna Marsh Park Tennis Court Rehab Page 5 of 24