Yard Drainage and Flooding

Your yard plays an important role in protecting your home from flooding.  A properly graded yard can minimize minor drainage problems and prevent more serious flooding conditions. 

Proper Yard Grading

In general, a properly graded yard will have some or all of the following characteristics:

• Ground sloping away from the house – the ground surrounding your home should be graded away from your house’s foundation to ensure that stormwater flows away from the house and not towards it.
• Pavement sloping away from the house – driveways, sidewalks and patios should be graded away from your house’s foundation to ensure that the stormwater flows away from the house and not towards it.
• Drainage path towards the city’s Stormwater Management System – stormwater runoff from your yard should have an unobstructed path towards the City’s system. Many residential properties have swales in the side and rear yards which carry water towards inlets within the yard, a neighboring yard or the street. Some properties are graded such that the stormwater can flow directly into a creek, ditch or basin.

Grading and Drainage Changes

Yard grading often changes over time due to both natural and man-made causes.  The following situations can impact yard drainage by changing the grading or obstructing the intended stormwater drainage path.

• Natural Changes

  • Ground Settlement – The ground surrounding your home, particularly the area close to the house’s foundation, may settle over time. This could cause the ground or any pavements to slope and direct stormwater towards your home. Settlement also could result in isolated low spots throughout your yard where water may collect.
    
    Where ground settlement has occurred and water stands where it did not previously, it may be a good idea to fill the depression with topsoil, gravel or whatever material was already there. 
    
    
  • Erosion – Heavy rainfall or sump pump and downspout discharge could cause soil erosion resulting in isolated low spots where water may collect.
   

• Man-made Changes

  • Landscaping – The installation of landscaping, including planting beds, berms and retaining walls, is the most common man-made change to yard grading and drainage. All of these activities could change the yard grading and potentially obstruct the intended path for drainage of stormwater from within the yard and from adjacent yards.
  • Home and Yard Improvements – Many common home and yard improvements could change yard grading and potentially create obstructions to the intended stormwater drainage path. Examples of common improvements that could impact yard grading and drainage include: 
    • House Additions
    • Patios or Decks
    • Fences
    • Sand Boxes or Swing Sets
    • Sheds or Gazebos
    • Pools

How Residents Can Help 

Know Your Yard

Homeowners should know and understand how stormwater drains within their yard and if their yard is intended to drain onto or through a neighbor’s yard or if adjacent yards are intended to drain towards their yard. Homeowners should also know what features of the city’s Stormwater Management System are present on their property.  Key features, such as storm sewers, overflow routes and basins, are typically located within dedicated stormwater management easements. The property’s plat is a good place to check if any of these easements have been dedicated on the property.

Consider Stormwater When Making Improvements

When planning a home or yard improvement project, consider how the grading of your yard and the drainage of stormwater may be impacted not only for your yard, but for your neighbors’ yards as well. Obtain any required permits and be careful not to alter the grading or create obstructions.

Keep it Clear

Ponding of stormwater within a yard often occurs due to clogged storm sewer inlets. If there is an inlet in your yard, please keep this drain clear of all obstructions including, leaves, grass and debris. Debris at storm sewer inlets also build-up after a storm event, which is a good time to check the inlet to make sure that the system will work well in the next storm. It is also important to never dump any debris, including but not limited to landscape waste, garbage or chemicals into a storm sewer inlet. If you cannot clear the debris yourself, please contact (630) 420-6095 to report the location.

How to Properly Drain your Swimming Pool

Whether chlorinated or neutral, swimming pool water that is discharged into your yard can cause problems for your downstream neighbors, the creeks and rivers and the environment.  The City of Naperville allows and encourages residents to discharge swimming pool water into the City’s sanitary sewer system which allows the water to be properly treated at the Springbrook Water Reclamation Facility before being released into the DuPage River.  This is allowed at no cost to the swimming pool owner.

Swimming pool water can be drained in the sanitary sewer system in any of the following manners:

1. Sanitary Manhole:  Homeowners can drain pool water into a nearby sanitary sewer manhole. Before doing so, please contact the Water Utility at (630) 420-6137 to provide the City a minimum 24-hour notice so a drain grate can be installed on the manhole for safety.
2. Outside cleanout:  Homeowners with an existing clean out in their yard just need to make sure they have water in all floor drains to prevent any chlorine smell from coming into the home.
3. Internal floor drain(s):  Homeowners may also use any floor drain inside their home. Before doing so, make there is water in all floor drains to prevent chlorine odors from entering the home. During the draining process the homeowner will need to monitor the drain rate to prevent any back-ups.