 |
 |
 |
 |
 |
 |
Frequently Asked Questions about the Lake Wingra Watershed
1. What is a watershed?
A watershed is the land area that drains in to a lake or river. Rain
that falls in the Lake Wingra watershed may fall on a roof, then down
a gutter, on to a driveway, down the street, then in to the storm sewers,
and down in to Lake Wingra.
2. Where is the Lake Wingra Watershed?
The watershed is mainly in Madison,
Wisconsin, but also extends in to the adjoining City of Fitchburg and
Town of Madison. Including the lake, Wingra Watershed is a 12 km radius,
mainly to the west of the lake. The lake is part of the Rock River Basin,
which you can surf at EPA's Surf
Your Watershed webpage. The Rock River eventually flows in to the
Mississippi River and drains down to the Gulf of Mexico.
3.Why are watersheds important?
There are no major rivers or streams flowing in to Lake Wingra, so the
lake is mainly fed by springs and stormwater runoff within the watershed.
Therefore, the runoff from the watershed makes up an important part of
the lake water. Runoff often picks up debris and pollutants bringing them
from the watershed to the lake, depending on how the land is used. For
example, think of the differences in runoff quantity and quality between
a parking lot and a garden. The parking lot contributes a lot more water
(because it can't filter in to the ground) and pollution than a garden.
The different land uses in the watershed have a big effect on the quality
and quantity of water in the lake, downstream in Monona, and beyond.
4. What are some of the problems in Lake Wingra, and
what causes them?
Unlike lakes that are polluted by industrial pipes or sewage inflows,
Lake Wingra has no major points of pollution. Instead, lake pollution
is a result of the small amounts of pollutants picked up from all over
the watershed. This is called non-point source pollution. Some of the
recent problems and their causes include:
| Algae blooms | Overfertilization of the lake by: lawn fertilizer running in to the lake, duck waste, pet waste washing down storm sewers, and nutrients stirred up from the lake bottom . |
| Swimming Beach Closures | Beaches are closed when bacteria counts are high enough to potentially cause illness. The bacteria sampled, such as e. coli or fecal coliform, may have increased due to wastes from ducks, swimmers, or pet waste washed in to the lake by stormwater. Algae blooms contribute to beach closures in that blooms are a good place for bacteria to grow. |
| Muddy water | The lake is not very clear because the bottom is frequently stirred up. This condition, known as turbidity, is a result of fine sediments brought in from the watershed by stormwater, and their constant resuspension by carp. |
| Weeds | Aquatic plants, while natural in Lake Wingra, have been a problem in the past. Milfoil, a non-native pond weed, invaded Lake Wingra and was able to grow so much that it caused problems for boats and smelled bad. Natural processes now limit weeds in Lake Wingra to a level considered close to normal. Some advocates are interested in reintroducing native plants that provide habitat and food to wildlife such as wild ducks. |
| Drying of Wingra Fen | The fragile and rare wetland on the west end of the Lake Wingra has shown signs of stress in recent years. there is evidence that pumping from wells has been disrupting the natural flow of springs to the wetland, and solutions are being sought so that those pumping the water could use stormwater, restoring a steady flow of water for Wingra Fen. |
5. What are local governments doing about the problems?
City, county, and state governmental agencies are all working to limit
the amount of non-point source pollution reaching our lakes. Here are
some of the steps local governments have already taken to help keep pollution
out of Lake Wingra:
| Storm sewer interceptors | Local storm sewers include "interceptors", devices which catch some of the bigger debris that flows in to the sewers, and which are cleaned periodically by the city. |
| Storm water detention ponds | Ponds like the one at the Odana end of Munroe Street help to trap sediments such as road sand which are headed for the lake |
| Streets weeping | Street sweeping helps to pick up the sand, debris, and pollutants before they wash down to the lakes. This is most effective in areas where street sweeping is more frequent. |
| Limiting Salt and Sand | Madison is progressive in controlling the salt and placed on roads, thereby limiting the amounts that flow in to the lakes. |
| Changing Homes and Gutters | The Lakes and Watershed Commission, UW Extensions, and DNR all provide information on how homeowners can help by routing their gutter runoff to their lawns, keeping storm sewers clean, and cleaning up after household pets. |
6.What can individuals do to help improve water quality
in Lake Wingra?
Watershed Residents
-
Pile leaves on the curb lawn for collection, so that they don't wash down the storm sewer to the lake.
-
Clean up after pets so that the 'fertilizer' from pet waste doesn't wash to the lake.
-
Route downspouts from roofs so that they flow on to the lawn or garden.
-
Where feasible, build a "rain garden"
-
Use minimal fertilizer and other lawn chemicals, if you use them at all, so that excess won't wash down to the lake.
Everybody
-
Minimize feeding of the ducks in Vilas Park so that they don't concentrate and "fertilize" there.
-
Dispose of all litter generated near the lake in proper containers, and participate in fun activities like lake clean-ups.
-
Join the Friends of Lake Wingra in their efforts to create an active watershed community.
7. How can you get involved in the Lake Wingra Watershed
Community?
Contact Friends of Lake Wingra.
8. What is an Equivalent Residential Unit (ERU)?
An average of the horizontal impervious area of single family residential
units within the city. The horizontal impervious area includes, but is
not limited to, all areas covered by structures, roof extensions, patios,
porches, driveways and sidewalks.
9. What is an Impervious Area?
The area of land, measured in a horizontal plane, that has a surface
that has been compacted or covered with a layer of material so that it
is highly resistant to letting water soak into the ground. It includes,
but is not limited to, semi-impervious surfaces such as compacted clay,
as well as streets, roofs, sidewalks, parking lots and other similar surfaces.
10. What is stormwater?
Water that directly results from a rainfall event.
11.What is a stormwater system?
Includes all natural and manmade drainage elements used to convey
stormwater from the first point of impact with the surface of the earth
to a suitable outlet location internal or external to the boundaries of
the city. The stormwater system includes but is not limited to pipes,
channels, catch basins, curbs, gutters, streams, ditches, wetlands, sinkholes,
pub stations, roadways, detention/retention basins, swales, ponds and
other stormwater conveyance and treatment facilities whether public or
private.
12. What is surface water?
All surface natural and man-made water bodies, including but not limited
to all lakes, rivers, canals, wetlands, sloughs, streams, territorial
waters and the ocean into which stormwater runoff directly or indirectly
discharges.