8- The Oakville Beaver Weekend, Saturday October 27, 2007 www.oakvillebeaver.com OAKVILLE - Celebrating 150 years! IS YOUR PROPERTY PROPERLY GRADED SO DRAINAGE WORKS? Oakville receives an average of 700 mm of rainfall per year. The heaviest of these events occur primarily in the spring and fall periods. Since the `70s, the Town of Oakville has been at the forefront in ensuring that newly developed lands effectively captured and restricted the volume of storm runoff to the local creeks and stream areas. Local neighbourhood roadways are designed as over-land flow routes when the volumes of runoff exceed the capacity of the roadway storm sewers. Residential lot grading designs were implemented to ensure that runoff from roof drains, yard swales and driveways could temporarily contain the storm flows and allow them to either migrate downward into the soil or gradually to the street catchbasins, sewers and eventually to the receiving storm water management ponds. Homeowners often undertake landscaping of their properties or install additional hard surface features that alter the effectiveness of the lot grading and drainage capabilities. Some of this work can result in blockage to the designed flow paths and in some cases negatively impact their own properties or that of their neighbours. The Development Services Department receives many calls from concerned homeowners about standing water on the property resulting from a neighbours previous landscaping project and/or other forms of grade altering activity. While homeowners have a right to undertake earthworks within their own property, they are encouraged to ensure there is no negative impact to any abutting lands. With the trend towards larger homes on smaller lots, a challenge exists to ensure that the remaining green space is designed to contain and handle the storm runoff. This usually results in areas of the rear and front yards graded with defined swales that may restrict amenity uses. The location of proposed fences, Did you know ... pools, patios and gardens need to be carefully considered as to the effects on storm runoff. HOMEOWNER TIPS! For homeowners considering yard alterations, here are a few helpful tips: that phosphorus is also a component mixed in our rainfall? · Contact the Town to make arrangements to view the originally approved drainage and grading plot plan for your lot. This will provide a perspective on how your lot and the abutting neighbour properties were designed to work together to convey storm flows. · Try to maintain the intent of the original grading designs with any project. For instance, this may involve realigning an existing swale under a new deck to allow storm water to flow unaltered or placing a new garden area away from an existing swale, allowing unencumbered flow. · Direct roof downspouts to any green space surface areas to allow the water to soak into the soil rather than run off the property. · Ensure that window wells have adequate gravel bases to allow the runoff to migrate downward and not build up resulting in basement flooding. · Slope the grading around the perimeter of the home in order that rain impacting the walls flows away rather than toward the foundations. · If you have a rear lot catchbasin in your yard, keep it free and clear ensuring that it functions as intended. · Some best-management practices such as rain barrels, green roofs and soak away swales are becoming quite common and are highly encouraged. · The Town's Site Alteration bylaw, 2003-021, a bylaw that regulates earthwork alterations to any property, is available on the Town's web site, www.oakville.ca and provides useful information to landowners. QUESTIONS? This article has been written by John Kwast, Director of Development Services, Town of Oakville. If you have any questions or want to learn more about what you can do to ensure your property enjoys trouble free drainage conditions, call the staff in Development Services Department at 905-845-6601, ext 3083.