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Photo
by Matt Kelly
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| The
garage-site stream has plunge pools that slow
the flow of the water, tree trunks and root wads to direct
the water and armor the banks from erosion, and a detention
basin to hold 100-year floodwaters. Trees and rocks from the
site are being used in building the stream channel. |
Changing water ways
By Matt Kelly
The
University is taking an innovative regional approach to storm-water
management, and state officials are praising the approach.
About
1,200 feet of Meadow Creek in the Dell will be brought back to
the surface as part of a plan for handling storm-water runoff
from portions of the Grounds, the Emmet Street parking garage,
the proposed arts precinct and the planned Massie Road multi-purpose
arena. The Universitys master plan calls for designing upstream
areas to control drainage in order to limit erosion, flooding
and the speed that water runs off into the citys storm drain
network.
The
regional approach is not new, but this combination of best management
practices and stream renovation is probably more innovative than
anything I know about in the state, said Richard Cooper,
an urban program engineer for the Virginia Department of Conservation
and Recreation. He has approved the Universitys storm-water
master plan and is reviewing its implementation plans.
The
University is a good citizen and cares about the environment,
said Lee Mallonee, landscape architect for Biohabitats
Inc., which designed the streams in the project. What is
truly remarkable here is the Universitys willingness to
look at all of its property and handle storm-water management
regionally, not just site by site. This kind of overall planning
is very cutting edge.
The
idea initially came in a mid-1990s report on the Universitys
water resources by Andropogon Associates, which first suggested
opening, or daylighting, Meadow Creek. Judith Nitsch
Engineers, who created the storm-water master plan, refined it
by incorporating the creek into the storm-water management steps
of several University projects.
Were
changing the approach to storm-water runoff from an engineering
problem to an environmental and aesthetic asset for the University
Grounds, said University landscape architect Mary Hughes.
The
majority of Meadow Creek on University Grounds was channeled into
underground pipes in the 1950s when the topography of the area
was changed to accommodate the McCormick Road dorms. The creek
starts on Observatory Hill and winds through an underground pipe
beneath Facilities Management, the Dell, under the Central Grounds
Parking Garage and Nameless Field, then comes to the surface on
the north edge of Carrs Hill Field, just before running
under the CSX railroad tracks. On the other side of the tracks,
it is an open stream that runs around the southern and western
edges of the Lambeth Field residence area, before going underground
again to cross Emmet Street. It flows open along Emmet Street
to Copley Road, where it enters the city storm drain at the low
point of its watershed on University Grounds. By slowing the flow
of storm water higher upstream, there is less impact when it enters
the city system.
Landscaping
at the Massie Road arena will be designed to accommodate drainage,
with water runoff from the arena channeled into grass swales containing
native plants to act as bio-retention filters and slowing the
flow.
The
Universitys approach links several projects with a single
regional system, instead of having individual detention basins
on each site. It also complies with the Chesapeake Bay Directive,
which calls for more creative management of storm water within
the bay watershed. Cooper has accompanied Hughes and Nitsch to
make presentations about the Universitys plan before government
and university audiences in Roanoke and Richmond.
For
the Dell, Biohabitats designed a low-flow stream to run to a one-acre
pond near the front of Lambeth House with an outlet into the underground
pipe. The existing pipes are being left intact and the stream
is being designed so that water flows exceeding 15 cubic feet
per second will be diverted from the above-ground channel and
flow into the pipe. Without the overflow pipe, the Dell would
flood during heavy rains, Mallonee said.
Hughes
said opening water to air and sunlight improves water quality,
and Linda K. Blum, an associate professor in the environmental
sciences department, will conduct research over several years
to gather data on the process.
Hughes
said the changes to the stream should reduce flooding at the Emmet
Street and Ivy Road intersection.
While
the construction of the Meadow Creek part is scheduled to start
in the spring, the re-channeling of the nameless tributary that
runs through the Emmet Street garage site is under way.
Biohabitats
designed the garage-site stream to have plunge pools
that slow the flow of the water, tree trunks and root wads to
direct the water and armor the banks from erosion, and a detention
basin to hold 100-year floodwaters. Trees and rocks from the site
are being used in structuring the stream channel.
David
Sweet, project manager at the Emmet Street garage, said the stream
was placed to accommodate not only the garage but also the student
housing planned for the front of the site.
Its
a win-win situation all the way around, Cooper said.
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