Wetland Project Background
In April 2023, A3 Environmental Consultant’s joint venture with Olson Ecological Solutions (A3E+OES) conducted a wetland project for an approximately 1.2-acre parcel planned for minor development by the landowner in Section 1, Township 40 North, Range 10 East, located in Medinah, Illinois in DuPage County. The purpose of the wetland delineation was to determine the location and size of wetlands associated with the potential placement of a pole barn. The project boundary was surrounded by residential lots and adjacent to a degraded cattail wetland on the north. Historically, the land use was as a pasture with the same wetland adjacent to the north.
Wetland Project Location
The wetland delineation was conducted on a 1.2-acre parcel located in Medinah, Illinois, in DuPage County. The site was bounded on the north by a cattail wetland with the remainder of the parcel surrounded by residential lots, which tapered to the east with a gravel access path. The location of the site was summarized in the Property Location Map in the Tieri Project Delineation Report 2023.
Wetland Project Scope
The consultants from A3E / OES conducted the wetland delineation in April 2023 using the technical guidelines as described in the Army Corps of Engineers Wetland Delineation Manual (Environmental Laboratory, 1987) and the Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Midwest Region (U.S. Army Corps of Engineers, 2010). The scope of the project included off-site procedures and a field investigation.
Wetland Project Methodology
The off-site review of the study area included an analysis of maps and aerial photography, determination of normal precipitation, and a review of wetness signatures on recent aerial photography. The field investigation took place over one day on April 10, 2023. After confirming the project boundary, the site was examined for the presence of natural or human induced changes affecting vegetation, soils, and hydrology, and was traversed in several places. Suspected wetland areas were explored with mapped hydric soils, saturation, or inundation visible on aerial imagery, areas indicated as wetlands by the National Wetlands Inventory, floodplains, and areas appearing as wetlands on historic imagery. Drainage patterns and depressions in the landscape were looked for, and a final walk-through of the entire site was conducted. Wetland boundaries were marked with flagging and GPS points were recorded to communicate a complex boundary to the U.S. Army Corps of Engineers (USACE).
Wetland Project Findings
The desktop analysis included an assessment of features in the project boundary to determine areas inclined to have potential wetlands based on the presence of hydric soils, wetland features, flood hazard risk, topographical features, and wetness signatures from aerial imagery. The project area was located along a terrace which had a slight slope. The highest area of elevation was to the southwest, decreasing in elevation as the property extended to the north boundary where it met the fringe of the cattail wetland. Three types of soil were present on the site: Markham silt loam, 2 to 4 percent slopes (531B) representing 75% of the property with 6% hydric rating; Muskego and Houghton mucks and Drummer silty clay loam were strong indicators of wetland presence in those areas. The wetland features identified within the project boundary included emergent vegetation, standing water, and hydrophytic plant communities. The flood hazard risk analysis revealed that the project area was located within the 100-year floodplain, with some areas having a high flood hazard risk due to the proximity to the adjacent creek. The topographical analysis showed that the site had a gentle slope, which contributed to the flow of water towards the cattail wetland on the northern boundary. The aerial imagery analysis provided wetness signatures that further supported the presence of wetlands in the project area. Overall, the desktop analysis revealed that the project area had significant wetland features and that the proposed development would require careful consideration and mitigation measures to avoid or minimize any adverse impacts to the wetlands.
In conclusion, the wetland project report for the Medinah, Illinois property in DuPage County provides detailed information about the site’s environmental conditions, including historical and current site features, wetland descriptions, and the methodology used in the investigation. The report is a valuable resource for landowners, developers, and regulatory agencies involved in the planning and development of the site. With the information provided in this report, all parties can make informed decisions about the use and protection of the wetlands on the property. The report also highlights the importance of conducting thorough wetland delineation studies to ensure the preservation of these valuable resources.
