After an uncharacteristically hot and dry June, Mother Nature just sent us a harsh reminder of her ability to restore rainfall statistics rapidly.
Unfortunately for many homeowners and businesses, this reminder came in the form of a seven-inch downpour over a 24-hour period that is still causing overflow and flooding around local rivers, lakes, and retention ponds.
Gurnee, IL experiences massive flooding
While it is difficult to predict and prevent the kind of flooding issues that are created by such catastrophic weather events, these events serve as a reminder to property owners, both commercial and residential, to be more aware of the impact that water flow has around your property. Having a well-conceived and expertly executed drainage system around your buildings and grounds can mean the difference between staying high and dry through any weather event, or dealing with flooded yards, basements, parking lots, and roadways.
Generally, rainfall is the catalyst for creating drainage issues but ground water, specifically the location of the water table, can also play a role in the ability of water to move by design. Where land is flat, soils are dense (clay), or the water table is high, a well-designed drainage system is a priority. Consideration of grading, water flow, and proper drainage is essential to prevent minor issues during normal weather and to minimize major damage during catastrophic events like the one we experienced here in northern Illinois last week. Without proper drainage systems in place, water can enter and undermine structures, damage drives and roadways, cause erosion issues, and drown expensive plant material.
It is not always enough to rely on the original drainage plans that were created for your property when it was first developed and constructed. Typically, the more recent the development took place, the better the chances are that the drainage systems were designed and constructed to effectively move water around the property. Older properties may have experienced settling, ground shifts, changes in water tables, neighboring development, or many other factors that can influence the effectiveness of these systems. New or old, it is a good idea to observe and review the water flow issues on your property before a major problem occurs.
SURFACE WATER is one of the more common problems associated with improper or inadequate drainage systems. Sites with clay soils will likely have issues with lingering surface water. By design, developed land should be graded to drain so that water flows through swales or sheet drains across turf or pavement to the curb or storm drain. The reality is that builders don’t always get their grades right and water becomes trapped, causing puddles on pavement, backflow against foundations, soggy zones in lawns, and muddy planting beds.
Downspout/sump pump discharge is a huge contributor to surface water issues. Enormous amounts of water can come off a building’s roof or be channeled into a sump pit during a typical rainfall. This water is often just re-directed back along the foundation of a building where it can go right back into the sump pit or collect on the surface of the ground around the structure.
SUB-SURFACE WATER collects underground, and becomes trapped when there’s poor drainage due to the existing soil structure or high water tables. When it freezes and expands, the potential for damage increases. The frozen water pushes against your foundation and paved surfaces, causing heaving, cracking, and structural damage.
Solutions to improper site drainage can range from the very simple to much more complex depending on the nature of the issue and its underlying cause. Conceptually, solutions fall into two basic categories.
- Capture the runoff and store it for reuse or allow it to percolate back into the soil. Rain barrels and cisterns are used for storage of runoff water for use later as manual watering sources. Dry wells, French drains, rain gardens, and specific soil amendments can be used to collect and redistribute water back into the surrounding soil.These solutions have many environmental benefits such as reducing runoff from your property, filtering runoff, watering your yard, and recharging groundwater.
- Intercepting and redirecting runoff provides an opportunity to safely discharge high volumes of water to a place away from the problem area(s). This can be done using swales, French drains, catch basins, underground pipe assemblies, or downspout/sump pump extensions with splash blocks. These methods of rerouting water can also be combined with other capture and storage elements to provide even more benefit.
Please make note that whenever you are redirecting runoff, you must send it to a suitable outlet. Discharging runoff to an unsuitable area will just move the problems downhill. Be aware that redirecting runoff without collecting it or allowing it to percolate into the soil can negatively impact neighboring properties.
The first step in solving drainage issues on any property is discovering that they exist. Problems like foundation seepage and erosion might not be obvious until a major issue develops at which point resolution can be expensive and complicated. To become aware of potential trouble spots, walk your grounds after a rainfall event and look for places where water has collected.
Does it take more than an hour or two to dissipate after a heavy downpour?
Are there signs of erosion around the downspouts or sump pump discharge points?
Are you finding soft, wet spots in the common turf areas that do not dry out readily?
Are you seeing a decline in the health and appearance of plant material located in the collection areas?
These are just a few of the signs that water is not percolating or moving appropriately around the grounds of your development or commercial property. Time to consider having an expert come out and assess the problems. ILT can do simple visual inspections or accurately read existing grades by laser transit to establish the exact topography no matter how flat the site may seem.and determine precisely where and why water is moving the way it is on your property. From that information, we can evaluate and present potential solutions for your consideration.
While last week’s flooding can serve as a reminder of the devastating impact heavy rainfall can have, it does not take a seven-inch downpour of water to cause damage around your property. Finding and resolving water flow issues before they become expensive problems is always a better solution.
Call ILT Vignocchi today and we can start a conversation about resolving water flow issues at your HOA or commercial building.