60
THE COUNTY’S NATURAL ENVIRONMENT
PLANNING ISSUE
Wetlands, which quietly
provide numerous local
benefits, are not completely
protected by federal and
state permits.
What’s New
•
Constructed wetlands, which are shallow marsh
systems planted with emergent vegetation, have
become more widely used as stormwater management
in new developments. Constructed wetlands developed
in the county over the past 10 years are effective in
pollutant removal, mitigation of peak rates of
stormwater, reduction in runoff volume and in
providing wildlife habitat benefits.
Geology
Climate
Hydrology
Floodplains
Air Quality
Steep Slopes
Soils
Wetlands
Woodlands
Wildlife
Natural Areas Inventory
Wetlands
Wetlands provide many benefits including erosion control,
flood retention, water quality improvement, groundwater
recharge, and wildlife habitat. They can also be attractive
and provide open space and recreation opportunities.
Wetlands are identified by the presence of hydric soils,
surface water, and wetland vegetation. The
(NWI), prepared by the U. S.
Department of the Interior, Fish and Wildlife Service,
generally identifies 6,931 acres of wetlands that are one acre
in size and larger within Montgomery County. More
detailed wetland delineations based upon hydrology, soils,
and plants have been performed on various areas of the
county. Typical county wetlands are riverine or pallustrine
due to their association with adjoining streams and rivers.
These types of wetlands are important since they can filter
out impurities in stormwater flowing into streams. The
wetlands also provide flood storage and offer unique habitat
for unique and endangered species such as the Muhlenberg
bog turtle (Clemmys Muhlenbergii).
In the past, some wetland areas in the county were drained or
filled for development. Over the last several decades,
changes to wetlands have been regulated so that any loss of
wetland area is mitigated with replacement wetland areas.
Though many replacement wetlands are on site, some larger
created wetland areas have been developed at several off site
locations including the Norristown Farm Park and along the
Sandy Run in Whitemarsh Township.
Though state and federal permits are required for most
construction activities in wetlands, these actions alone do
not protect wetlands. Other measures by local government
including zoning restrictions that provide setback
requirements and lot size restrictions on properties
containing wetlands, vegetation protection standards, and
open space acquisition and set aside requirements have
been used to ensure that wetlands continue to provide
local benefits.
Wetlands which contain aquatic and amphibious animals,
and different species of grasses, sedges, and wild flowers are
important habitat. They provide nesting sites for waterfowl
as well as resting spots for migratory species. Most aquatic
Many wetlands such as this one in Lower Pottsgrove Township are
preserved as open space.
Vernal ponds provide important habitat for water fowl, reptiles and
amphibians.
