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Wetlands
In 1836, when William Burt
walked this land with his original survey crew, he
drew this map.
The land that was to become
Havenwoods is outlined in red. You will notice a
wetland area in the northeast corner – near where
the education center sits today. People, time,
drainage tiles, and bulldozers completely
transformed this land during the 170+ years since
the survey.
The
wetland in the northeast corner was long ago
drained, filled, and built upon. Today, there are
two wetland areas and a creek at Havenwoods.
South Pond
The South Pond was
constructed in
1983.
The picture below (from
1987) shows a group of kids enjoying a summer
afternoon at the pond. As they scooped for tadpoles
and dragonfly larvae, they learned about the
importance of wetlands for plants, animals, and
people.
In spring, this pond is
usually full of water from snow melt and spring
rains. In most years, it dries up by mid to late
summer. The water level fluctuates because the pond
is fed only by precipitation and runoff.
Nevertheless, it provides a place for leopard frogs
to breed, migrating water birds to rest, and many
animals to drink and find food.
Take time to stop by the
South Pond on your visit. You never know what you
might find.
Leopard frog
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Lincoln Creek
Take a close look at that map from
1836. You’ll notice that
Lincoln Creek didn't even exist! An 1869 plat map
shows a creek, identified in other sources as Mud Creek, just south of
Havenwoods’ western border.
A 1932 topographic map finally shows a creek flowing
through Havenwoods.
At this point
you may be wondering, how does a creek appear out of
nowhere? Our best guess is this: as farmers
converted the lowland forest to farmland, they
needed to drain the land. Lincoln Creek probably
started out as a drainage ditch. As more land was
cleared, the ditch grew.
Slowly during
the 1940s, '50s, and '60s, the city of Milwaukee
encircled Havenwoods. Rain fell on impervious
buildings, roads, and parking lots. With no place to
soak in, the rain followed the slope of the land to
end up in creeks and rivers. By the mid-1970s, Lincoln
Creek couldn’t handle the volume of water that ran
off after big rainstorms.
At some point
it was straightened, an attempt to move more water
faster, but there was just too much water.
Between 1960
and 1997, almost 2000 flooding problems were
reported in the Lincoln Creek watershed, as
basements, ground-level floors, and yards were
flooded.
Each year brought fewer places for the water to go
and more severe flooding.
And that brings us to the
need for flood control . . .
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Flood detention basins
Look back at William Burt's 1836
survey map one more time. Notice the three wetland
areas. By the mid-1970s, those wetlands were long
gone. People had spent years converting wetlands to
farmlands and then cities. They tried to handle
rainwater by making the creeks straight so they
could drain water faster. They even lined them with
concrete to increase the water speed. Sadly, it took
over 150 years to realize that the best way to
handle rainwater is to have wet, open places for the
water to collect and soak in – similar to those
wetlands that William and his survey crew
encountered years ago.
From 1970 to 2000, plans to
construct flood control ponds at Havenwoods were in
the works. In 2000, the Milwaukee Metropolitan
Sewerage District began construction of three
detention basins at Havenwoods. The work here was
part of a comprehensive plan to reduce flooding in
the Lincoln Creek watershed.
This picture from 2002 shows
the work in progress. On the right you can see
Lincoln Creek. The creek was moved east, widened,
and sculpted with graceful curves. A berm (middle of
photo) separates the creek from the detention
basins (left side of photo). During a heavy rainstorm, the floodwaters
flow over the berm to be stored in the detention
basins. Some of the water soaks into the ground.
The rest is slowly released back into the creek
through adjustable weirs. You can see one of the
weirs in the photo just to the right of the person.
Today, the area is still recovering. Animals
like waterfowl
quickly found the ponds. Muskrats, raccoons, deer,
and other mammals come to the water for food and
drink. Toads and other amphibians call from the
basins in spring. It is taking longer for reptiles,
like the Butler's gartersnake, to return to the
area.
Invasive plants are a huge
problem in the basins. They took advantage of the
disturbed soil during construction, and they are
difficult to manage.
Visit the flood control area
for a great view from the pedestrian bridge (in
photo below) and a walk out on the floating pier.
While you are there, take a look at the interpretive
signs which describe the operation of the flood
control structures, the history of the area, and the
vegetation that you can see.
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