Cities are grappling with storm water run-off more than ever as storms become more violent and development increases leaving less permeable land. In heavy rains, sewers sometimes aren’t able to handle the downpour that might happen (think Toronto in July, 2013, or Montreal, May, 2012). Encouraging more permeable areas allows the ground to absorb water helping to alleviate some of the pressure on sewer systems. Sometimes, however, finding the right solution to increasing permeability can be a challenge. Laying down loose gravel over ground makes it difficult to plow in winter, while small stones get caught in pedestrians boot treads get dragged indoors, ruining floors. Another challenge is that sometimes permeable paving needs a strong, impermeable base so that the blocks don’t crack under the weight of vehicles or develop ruts in the most heavily traveled areas. It kind of defeats the purpose of permeable pavers.
A great product originating in Germany, is Ecoraster, a grid system that is used to keep surfaces permeable. It can replace paved parking lots, driveways, pathways and can be used in various agricultural applications as well. The Ecoraster is available in different levels of durability depending on intended use.
It is an extremely versatile product and can be used in a variety of urban situations.
Parking lots and driveways: It can be used as a permeable base stabilizer, meaning that it can be laid down underneath interlocking pavers and keep them stable. The grid itself can be laid on prepared ground, excavated 6-8 inches. This depth is significantly less than the 18 inch base that a poured concrete foundation needs and can save tipping fees for excavated fill in high cost areas such as Toronto (not to mention the cost of the poured concrete). The grid is filled with clear aggregate gravel, then interlocking pavers can be put over it.
However, it can also be left as is — used with just the aggegate, — or seeded with grass.
Hillside erosion control: In areas where it is difficult for vegetation to grow, Ecoraster grid will stop plants, soil, grass, vegetation from drifting and allow it to take root.
It has been in use in Europe for 20 years and has a proven track record along with a 20 year warranty.
Made from 100% post consumer recycled plastic bags, the final product is a low density polyethylene (LDPE) plastic which is cold and heat resistant and doesn’t crack or break with extreme cold or heat. It is also 100% recyclable at end of life.
Used in northern European countries, when used on its own (without a top layer of pavers), it has shown a 90% reduction in salt use. Snowplows have no difficulty clearing grid areas.
The Ecoraster system comes in a variety of strengths depending on where it will be used. The cost for the product (excluding installation) ranges from $2.25-$4/square foot.
For parking lots it even comes with line markers that attach to the grid to mark parking spaces. They are UV resistant and can save maintenance costs on repaving lines.
Good for municipal parking lots, residential driveways, public and private pathways, hillsides where soil erosion is possible.
For more information visit the Ecoraster website or the North American distributor, Purus North America, 1-800-495-5597.