Permeable Paving: Stormwater Management For The Future

Ecoraster grid product on a road surface

Authors: Jason Brooks & Mike Coates, Co-CEOs, Ecoraster

With the predicted increase in precipitation and storm events over the coming decades, the issue of how to effectively manage stormwater is becoming more pressing than ever before.

From the water we drink, to the snow that we play in, and the tennis courts we socialize in, all are affected by permeable paving. Groundwater is our source of drinking water, and precipitation can carry harmful chemicals - once those chemicals fall onto the ground and pavement, without a proper filtration system which is included in a permeable solution, those chemicals go back into the environment, including the air and the land. Permeable paving systems help safeguard our health by safely disposing of stormwater runoff.

More and more, we have been “paving paradise” and sealing up areas that were nature’s way of managing stormwater. Permeable paving systems have been developed as a way to “return to nature” and allow stormwater to be managed on-site “where it lands”. Permeable systems are designed not to pave over surfaces, but to become a part of them. The porous surface allows stormwater and water from thawing snow to seep back into the ground rather than running off. By allowing the stormwater to become groundwater, permeable paving becomes a crucial part of water’s natural cycle.

It goes without saying that we’re already seeing the effects of increased stormwater in urban settings. Noticeable uptick in hurricanes across North America and flooding in major cities such as New York, California, Louisiana and Texas, to name a few. Projections of future precipitation in a scenario that scientist’s term “business-as-usual” (i.e., a future where emissions continue at their current rate) project annual rainfall to increase by almost 100 ml over the coming century.

As the earth heats up, the risk of increased storms in precipitation-prone areas is becoming more acute. While it’s a lesser-known effect of the developing climate crisis, stormwater will nonetheless drastically affect life in many places and particularly in cities, where the higher density of paved surfaces means that the consequences of stormwater runoff are exacerbated. The growth in major city centers and the areas surrounding is far surpassing the ability of the existing municipal infrastructure. Not only are the existing sewers and drainage systems unable to manage the increasing volumes of stormwater, but they are also aging and starting to disintegrate.

This has the potential not only to increase flooding, but also to incur costly and more frequent infrastructure maintenance due to debris being carried into and blocking storm drains. It also poses a risk to the water supply, as factory runoff, chemicals from fertilizers, and other pollutants, such as pet waste, get carried by stormwater traveling over pavement, eventually ending up in SWM (stormwater management) ponds or even contaminating rivers and natural waterways. This contamination can result in serious repercussions for wildlife outside of cities and cause ripple effects all the way into regional biodiversity, and throughout the food chain.

These repercussions are certainly the effect of stormwater; however, they are also attributable to the way that municipalities deal with stormwater. While the effects of climate change cannot immediately be reversed, they can be managed through effective planning and infrastructure, including built-in stormwater management. With the exception of parks, trails and some historic districts, a large percentage of spaces in major cities, such as Toronto, are completely paved with asphalt. This impervious substance has been in wide use across the world for over a century, and while it may have been suitable for the conditions of the past hundred years, asphalt is decidedly not a material that can carry us into a sustainable future.

Change can be hard, understandably, but rest assured, permeable paving systems have been successfully used for over three decades across Europe alone. In Europe, landowners are taxed according to the percentage of impermeable surface and homeowners are even forbidden from using solid surfaces such as asphalt for their driveways. The concept that there are incentives and often grants available towards the inclusion of permeable surfaces is something that should be adopted across North America. The realization that when homeowners include permeable surfaces rather than conventional asphalt, municipalities benefit as well, is something that should not be taken lightly. There are even cities which offer additional tax benefits and credits to landowners when they design their facilities to manage additional/overflow stormwater from nearby properties.When individuals are responsible for managing their stormwater on site “where it lands”, both landowner and municipality benefit!

Supporting the individual to make these changes is important, however, the greatest and most effective changes happen when we “lead by example”.

It is imperative that municipalities “practice what they preach” and start including permeable paving surfaces for their facilities as well. All on-ground parking lot surfaces should be permeable, there is no question. All commuter parking lots, all nature pathways, all school parking lots...even sidewalks – And, as an added benefit, many permeable systems are also used as “solutions” for problematic areas. In older city centers especially, there are often underground obstructions such as mature tree roots, pipes and cables that greatly limit the depth of base able to be excavated. Many of these systems can be used as a base reinforcement, allowing you to reduce the required base depth by up to half while ensuring the strength of the base is not compromised. In these situations, permeable systems can also be used as the surfacing material, providing additional benefit to the area with onsite storm water management. Win-win for everyone!

It is easier to “go permeable” than you may think. There are many permeable paving systems that offer a scalable and affordable solution to flooding and stormwater pollution in cities.

Made in Canada of 100% recycled plastic bags, ECORASTER® permeable paving system of interlocking tiles creates a solid, permeable surface with a guaranteed lifespan of more than twenty years. Ecoraster fits into most municipal budgets, requires less maintenance than traditional asphalt paving, and is AODA / ADA compliant. Able to stop stormwater runoff in its tracks, halt the flow of debris into drains and ponds, and withstand up to 800 tonnes of pressure per square meter, Ecoraster permeable paving is designed with the future of our cities in mind.

To find out more about the available range of Ecoraster paving products and their uses, contact ECORASTER®. A trusted group of Ecoraster distributors are ready to assess the needs of each project and help determine the best Ecoraster product to deliver a durable permeable paving solution. Visit https://www.ecorastergrid.com/ to find out more.