The Embarras River rises inside Champaign County, and its upper reaches run through detention ponds, the southern part of the University of Illinois campus and Meadowbrook Park in south Urbana. The Kaskaskia River also rises in Champaign County, near Urbana. Where a river begins does not tell you where water will go on a particular lot.
Key takeaways
- The Embarras River rises inside Champaign County, and its upper reaches are the part that passes through Champaign and Urbana.
- Upper Embarras water runs through detention ponds near Windsor Road and U.S. Route 45, the southern campus and Meadowbrook Park.
- The Kaskaskia River also rises in Champaign County near Urbana, so the county has more than one river that begins here.
- A river's source is not a flood map. Water reaches a property by the ground, drainage and grade around it.
- To check an address, ask the local building office or drainage authority, and look at the lot's grade and drains yourself.
Where does the Embarras River begin?
The Embarras River rises inside Champaign County. Its upper reaches run through the southeast of Champaign, the southern part of the University of Illinois campus and Meadowbrook Park in south Urbana.
The river's upper course is the part that touches the two cities. Water there moves through urban drainage, detention ponds and open land, and the route it takes is shaped by the ground and the drains around it. Those details change from one block to the next.
The University of Illinois Library's guide to Illinois waters describes the river's course and the places it passes. It is a useful starting point for understanding the river, and it is not a record of any one property.
Where does the Kaskaskia River begin?
The Kaskaskia River also rises in Champaign County, near Urbana. Its headwaters are in the county, and the river runs on from there, well beyond the county line.
The Kaskaskia's beginning in the county is a fact about the river's source. It does not tell you that the river has flooded any particular street near Urbana, and this guide does not claim that it has.
A person who wants to know how the Kaskaskia behaves near a particular property should ask the local drainage authority, the building office or the state agency that records river levels. The crew reads the water on site, rather than using the river name.
Why does the river's source not tell me about my lot?
Water reaches a property by the route the ground gives it. A lot's grade, its drains, the ditches beside it and any low corner decide whether a storm or a flood will reach the house, whatever river is named on the map.
Two houses on the same river can have very different experiences. One sits on a higher lot that drains away, and the other sits at a low corner where water collects. The river is the source of the wider water, but the building's own ground decides how it arrives.
The same applies to storm water. A detention pond or a blocked drain can send water toward a house even when the nearby river is not high.
How do I check my own address?
Look at the grade of the lot, the position of the drains and ditches, and where the water went the last time it rained hard. Then ask the local office that keeps drainage and building records, which can show what is known about your address.
Walk the lot after a heavy rain and note where the water stands and where it runs. Check the gutters and downspouts, the window wells, the garage threshold and any low corner. Photograph what you see.
Ask the building office for the records for your address. The City of Champaign and the City of Urbana building departments answer questions on repairs and permits inside their cities, and the drainage authority for the area can answer questions about ditches and culverts.
Compare what you see on the lot with the records the local office holds. A ditch that is marked on a drainage plan, a culvert that is listed as the outlet for the block, or a pond that is recorded as serving the subdivision all help explain the route water takes, even when the record does not show how much water it carries in a storm.
What does the regional flood record tell a homeowner?
The U.S. Geological Survey reported that the upper Embarras River basin had main flooding in Illinois in December 2015. That is a regional record. It does not describe a particular street, and it does not predict the next event.
A regional record shows that river flooding has happened in the basin. It helps a homeowner understand that the river can reach a building here, and it is a reason to know the route the water would take.
It is not a measure of risk for a particular address. For that, the lot itself and the local records are the better source.
Do the rivers affect water in homes that are not near them?
They can, indirectly. A high river can back up storm drains and raise the water table, and storm water from a wide area can reach a low lot far from the river. The route, not the distance, decides the effect.
A storm drain that empties toward a river can back up when the river is high. Water can then come up through floor drains in buildings that are some distance from the river itself.
The crew checks the drains and the route on each call, rather than assuming the river is the reason.
What should I do if I want to prepare my property?
Know where your main shut-off is, keep the power route to the lower rooms clear, check the grade and the gutters, and keep a list of the people and phone numbers to call. A plan made before a storm is easier to follow than one made during it.
Clear the gutters and downspouts so they carry water away from the foundation. Check that window wells are clear and that the ground slopes away from the house. Those are the routes most likely to bring water inside.
Keep the line's number in your phone. A call can be made at any hour, and the crew will tell you what to do until it arrives.
Who manages the rivers and the ponds?
Rivers, drainage and stormwater ponds are managed by public agencies and by the owners of the land and the ponds. This company does not manage them and cannot change how they work.
A question about the river's level, its records or a pond's maintenance should go to the agency or owner responsible for it. The crew can tell you which route the water took to reach your building, which can help that conversation.
A blocked ditch or drain on private land is the owner's responsibility. A blocked public drain is the authority's.
What is a watershed, in plain terms?
A watershed is the area of land that drains into one river or one lake. Every drop of rain that falls inside it finds its way toward the same outlet, by surface runoff, ditches, storm drains or streams.
Champaign County contains parts of more than one watershed, and the Embarras and the Kaskaskia both begin inside the county. A building's place in a watershed tells you where its rain ultimately goes, but not how fast the water will arrive at the foundation.
The speed and the route are set by the ground, the paved surfaces, the drains and the slope of the lot. That is why two addresses in the same watershed can see very different water in the same storm.
How does a detention pond affect a property downstream?
A detention pond holds storm water for a time and releases it more slowly than it arrived, so that the peak flow reaching a stream or a drain is lower. The pond does its job by holding water, and it can overflow when a storm exceeds that capacity.
Downstream of a pond, the water it releases still needs a route. A ditch, a low corner or a drainage path that was not designed for the flow can carry it toward a building. For that reason, a pond that works as intended can still be the source of water that reaches a house.
Who maintains a pond and its outlet depends on the site. The owner of the land, a developer's association or a public authority may hold that duty, and questions about a particular pond should go to the one that maintains it.
Frequently asked questions
Does the Embarras River flood Champaign?
The upper Embarras runs through the southeast of Champaign, and the regional record shows flooding in the basin in December 2015. Whether a particular Champaign property is reached depends on its own ground and drainage.
Does the Kaskaskia River flood Urbana?
The sources describe the Kaskaskia as rising in Champaign County near Urbana. They do not describe a flood on a particular Urbana street.
Where can I see the flood records for my address?
Ask the local building office and the drainage authority for your area. The crew can also describe the water route it sees on your lot.
Is a river's source the same as a flood zone?
No. A river's source is where it begins. A flood zone is a mapped risk area, and that is a separate record kept by the public agency that maintains it.
Does this guide tell me my risk?
No. It explains where the rivers begin and why that does not decide the water on a lot. Your risk depends on your address, and the local records and a site visit are the way to check it.
What should I ask the drainage authority?
Ask who maintains the ditch, culvert or pond nearest the property, what the outlet is, whether the drain has been cleared recently and whether the authority keeps records of past blockages or overflows for the area. Write down the answers and the date.
Is a wet lot a sign that the river is the cause?
Not by itself. A wet lot can come from rain that falls on the property, from runoff across neighboring ground, from a blocked drain or from a river that is high. The crew reads the route and the timing, and the answer is usually a combination.
Sources
- University of Illinois Library, Illinois Waters guide
- Wikipedia, Kaskaskia River
- U.S. Geological Survey
This guide is general information for Champaign County homeowners, not a substitute for an on-site inspection. Prices are estimates. See our disclaimer.