City of Minneapolis, Hennepin County, and
the Mississippi Watershed Management Organization, which is based in Minneapolis.
Rising to these challenges, the project team
developed an innovative stormwater collection and reuse system, a circulatory snowmelt
system, and a low-impact landscape design.
Although largely invisible to the thousands
of people who pass through the station each
day, these novel approaches to stormwater management are
among the station’s most notable features.
The first of its kind in Minnesota, the stormwater collection system captures rainfall and snowmelt runoff year-round from the plaza on the third level, from two large
green roofs, and from the light-rail bridge and station platforms. Rainwater and snowmelt enter surface drains on the
plaza and the bridge and flow through pipes to two cisterns
located below the bridge on the station’s second (ground)
level. The two 15 by 15 ft cisterns have a combined storage
capacity of 40,000 gal. Stored temporarily in the cisterns,
the stormwater is pumped at a rate of 9 gpm to the HERC,
which passes the water through a sand filter and reuses it in
various industrial processes.
Because every square inch of the site was needed for com-
muters and other users of the station, the area around the
station afforded little room for snowplows, and there was
even less room for shoveled snow. In devising a solution, the
project team took advantage of the waste
heat from the nearby HERC and created a
system for melting snow. All of the station’s
concrete surfaces and the HERC parking ar-
eas form part of an integrated snowmelt sys-
tem designed by the Minneapolis-based firm
Michaud Cooley Erickson.
After a snowfall, accumulated snow is melted by approximately 50 mi of glycol-filled tubing that runs beneath a significant part of the station’s pavements and plazas. Once the snow has melted, the glycol is
returned to the HERC, reheated, and then routed back through
the tubing in a continuous process. This system will eliminate
the maintenance and labor costs associated with shoveling and
plowing snow and distributing sand and salt, which is normally used in the winter to help melt residual snow and ice. The
snowmelt system will also extend the life of all of the project’s
concrete since it will reduce the amount of expansion and contraction that the concrete undergoes in response to the melting
and refreezing that are typical of a Minnesota winter. All told,
including runoff from melted snow, the water system will capture approximately 3 million gal of runoff per year and convey
it to the HERC, reducing the center’s overall demand on the municipal water supply.
In addition to the system for collecting and reusing runoff, Target Field Station implements several low-impact
landscape and stormwater collection
Situated in a highly urbanized
site, the 104,000 sq ft Target
Field Station was carefully laid
out to accommodate elevated
light-rail train tracks and a sup-
porting bridge, as well as such
features as pedestrian plazas
and a 1,000-seat amphitheater.
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