On a Wing and a Prayer: A Wetland Mitigation Dilemma
Background:
Oil spill by Northstar Refinery Company of Duluth
$80,000 in settlement
Short amount of time to set plans in motion
Goal: restore lost wetland attributes, mainly to benefit migratory birds
Northstar Wetland
12 acre
Old dirt road and odd berm; Snowmobile trail
through site
Expanses of meadow and bog (pre-established
wetland)
Slightly above water table
Biggest Problem:
Road, berm, and snowmobile trail
Invasive grass over half the site (low habitat
diversity); could remove invasive grass and plant
native grass to improve species diversity—need
broad-spectrum herbicide plus 4 annual
treatments ($12,000). Hopefully, native plants will
reestablish.
Potentially benefit: coots, red-winged blackbirds,
yellow-headed blackbirds, snapping turtles, and
wood ducks
Lack of trees; need deeper water (could build
pond—expensive and little drainage to potential
pond)
Could build a dike (embankment) but this is
expensive
Recommended: Build berm and put culverts in old
road to improve water flow patterns ($21,000)
$33,000: Water moving through site, treat invasive
grass (and hope native species move in).
Native grass might spread clonally or by seed onsite
Pike Point
3 acre
Former industrial site; asphalt road with no
wetland qualities
Adjacent to St. Louis River—increased chance
that migratory birds would use habitat
800 feet lower
Remove road and re-do site, but without
planting new grass, they could get a bunch of
weeds
Could create mix of open water and emergent
vegetation with lots of edge to support target
wildlife species
While beneficial, a wooded swamp and wet
meadow are too expensive.
Planting costs would include windbreak to
reduce coal dust blowing onto the site
Issue: cost; need to spend a lot of money to
get land to be the same quality as Northstar is
now
$61,000 for removing road and debris, fill and
regarding to create wetland; let seeds blow in
Would cost $160,000 for revegetation
Questions:
1. Wetland mitigation is “wetland enhancement, restoration, creation and/or
preservation project that serves to offset unavoidable wetland impacts”
(www.ducks.org). Wetland restoration “reestablishes or repairs the hydrology,
plants and soils of a former or degraded wetland that has been drained, farmed or
otherwise modified since European settlement. The goal is to closely approximate
the original wetland's natural condition, resulting in multiple environmental
benefits” (Minnesota Dept of Ag). I think wetland restoration is more to restore the
ecosystem to its natural state, while wetland mitigation is to benefit human
interests while still restoring the wetland. Also, mitigation can be on- or off-site.
2. The main goal of the USFWS is to use the $80,000 to clean up the pollutant at
Northstar and then restore the damage to the wetland habitat and wildlife. They will
do wetland mitigation to fix the sort of balance in the ecosystem that was harmed by
the oil spill. With this balance, they can restore the exact habitat that was harmed or
restore a similar habitat for the same cause. The goal is a direct response to the
pollutant spill at the refinery, but their goal extends past just fixing the damage, as
they hope to make the restored wetland a home for migratory birds.
3. The refinery should be responsible for cleaning up the pollutant because the effects
will not be temporary if they leave the oil in the wetland. If someone makes a mess
they should clean it up! And a spill will effect the water wildlife which is essential to
a wetland ecosystem.
4. The team needs to remove the road at Pike Point in order to have space for the
wetland. At Northstar, the road goes through the wetland, but is not so big that it
takes up all the space at the wetland. Also, if the team removed the road at
Northstar, the road would just be moved to another wetland. The team is probably
more eager to change the landscape of Pike Point because they are basically starting
from scratch there, while at Northstar, there is already an established wetland.
5. The landscape at Northstar is already flat and there is little water flowing from the
watershed into the wetland. The ecosystem that has already taken hold is this area
is probably best for that landscape because that is how natural selection works. The
landscape is lower in elevation at the Pike Point location so more water probably
drains to that area. Also, if they make this area deeper, it would probably blend into
the channel that leads to the St. Louis River. This would lead to many possibilities in
future habitats for the area.
6. If the team applies herbicide to Northstar, but the native grasses don’t grow back,
then they could have opportunistic weeds occupy the area and cause more trouble.
Also migratory birds may not find this location because it is not along the river. If
they don’t change the watershed pattern here, the wetland could also dry up. At Pike
Point, weeds could take over the area or coal dust could cover the new plants and
they could die. Also, the mitigation of Pike Point would be very expensive.