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The Natural Lands Trust
staff occupied a farm house in the Hildacy Preserve until more
operational office space was needed. The Natural Lands Trust’s new
10,000 square foot headquarters was constructed adjacent to the
farmhouse on an old foundation of a garage. At the time of
construction, the organization also received a grant to complete a
long-planned project to convert a pond on the property into a wetland. The pond was a man-made spring-fed pond called Hildacy and was converted
into a wetland in Spring 2002, taking nearly a year to complete. The
pond had suffered from stagnant waters, high nutrient levels, bacteria,
algae blooms, and little biodiversity in and around the pond due to the
lack of oxygen within the water. Nearby runoff was discharging into an
overloaded unnamed tributary to Crum Creek, leading to water quality
and quantity issues in the Schuylkill River watershed.
The runoff is now
collected from a 2-acre area surrounding the wetland and is filtered for
pollutants and sediments before returning into the ground to recharge
aquifers. For a site plan of the design, click
here. The design of the landscape around the new building included
native plantings of pinxterbloom azaleas, serviceberry, rosebay
rhododendron and mapleleaf viburnum, which mitigate the problem of
stormwater run-off generated by the new construction. This stormwater
treatment wetland measures about 8,000 square feet and was created to
detain stormwater as flood prevention, decrease environmental
pollutants, educate the public, and benefit wildlife since native plants
provide habitat and a source of food. A sediment forebay receives water
from the roof of the new office, and measures 20 by 45 feet.
The water was first
drained from the pond, and fish were relocated. The basin was filled
with soil, some of which came from the excavation associated with the
new headquarters building. The basin was graded to different depths,
and NLT staff planted 16 trees, 150 shrubs, and over 500 wetland
perennials. Flood-tolerant species such as bulrush, arrowhead, soft
rush, and pickerel weed were planted. For a complete plant list, click
here. Dead logs were placed in the wetland to create additional animal
habitat. Mallard ducks and Kingfishers are regularly sighted in the wetland, and Red-winged
Blackbirds nest there.
Additional plantings
have since been added to reinforce the buffer between the tributary and
the wetland. Invasive species monitoring is also part of the continuing
maintenance plan. The sediment forebay has not yet needed to be cleaned
out and should not need to be cleaned for many additional years since it
simply receives most water from the headquarter’s roof.
The
organization wishes to raise awareness about the importance of wetland
ecosystems and effective management of stormwater runoff. The project
serves as a demonstration site to educate the public, and interpretive
signage has been erected to document the wetland project. About 7,300
visitors come to the preserve per year.
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