Baldwin County Wetland Conservation Plan - Alabama Department ...

Baldwin County Wetland Conservation Plan Final Summary Document
Question 5. Is the observed wetland free of ditches as indicated by the absence of the NWI “d”
special modifier?
Rationale: The presence of ditches significantly alters the hydrologic regime of a wetland
and reduces its ability to hold and slowly release water to the water table or aquifer.
Consequently, the functional capacity to store water is diminished. This variable was
identified remotely through digital NWI data.
Data Column: ditch; subtract 1 point
Question 6: Is observed wetland inside the zone of influence (designated wellhead protection
area for the 10 year time of travel capture zone) of a major groundwater pumping
center (withdrawal rates of three to four million gallons a day)?
Rationale: Depressional wetlands within the Project area depend partly on groundwater
discharge for their hydrologic requirements. Proximity of a wetland to a groundwater
withdrawal well, which lowers the groundwater level within the zone of influence, could
affect the hydrology of a wetland by lowering the water table. A wetland within the zone
of influence of a groundwater withdrawal well would be more likely to exhibit a reduction
in the groundwater table and would thus store more water than a wetland outside the
zone of influence of a large groundwater withdrawal well. Since this variable deals with a
human-induced condition, a “no” response will not count against a particular wetland.
Rather, it will serve as a bonus question allowing a wetland extra consideration if this
variable applies. This variable was identified remotely through digital maps provided by
the EPA.
Data Column: wellhead; 1 point bonus
Sediment/Toxicant/Nutrient Removal
Question 1: Does the adjacent land use surrounding the observed wetland fall into one
of the following land use categories: residential, commercial, industrial,
transportation, mixed urban use or agriculture?
Rationale: The assumption is that developed or agricultural lands which surround a
wetland would increase the nutrient, sediment, and toxicant load (fertilizer, animal waste,
polluted runoff) entering the system. Thus, a wetland in this position would have an
increased opportunity to cycle nutrients and filter water exiting the system. Since this
variable deals with the issue of opportunity rather than functional performance, a “no”
response will not count against a particular wetland. Rather, this will serve as a “bonus”
question allowing a wetland extra consideration if this variable applies. This variable was
identified remotely through digital land use data from FEMA.
Data Column: STN_LULC; 1 point bonus
Wildlife Habitat
Question 1: Is the observed wetland free from government maintained roads?
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