Low Impact Development
Low Impact Design Strategies for Rainwater
Charlie Penland

“By employing LID features, water is treated by the soil and plants, improving water quality, and reducing erosion and downstream flooding impacts.”

Rainfall brings the nourishment upon which life depends. Rain for urbanites is often considered a nuisance; however, for farmers it is everything. But when we haven’t enjoyed a good rainfall, we all become concerned. It is one of our most valuable resources. So why do we try to get rid of it so quickly when we can reap great benefits from each rainfall?

When we look at Low Impact Development (LID), it is important to understand these dependencies and design the water management systems to mimic nature as closely as possible to serve local and downstream needs. It’s important to look at the natural order of rainfall runoff and to use that knowledge to design cost-effective and environmentally enhancing drainage solutions.

By employing LID features, water is treated by the soil and plants, improving water quality, reducing erosion and downstream flooding impacts, and recharging ground water aquifers. There are many practices that have been used to adhere to these principles such as bioretention facilities, rain gardens, vegetated rooftops, rain barrels, and permeable pavements. These features can reduce the cost of drainage infrastructure and the land needed to support it.

LID principles are beginning to gain acceptance, although as engineers and design professionals, it’s important for us to work closely with governmental entities to communicate the many benefits that can result from implementing these principles. By putting these into practice, water can be managed in a way that reduces the impact of built areas and promotes the natural movement of water within an ecosystem or watershed.

Charlie Penland / P.E., LEED AP
Charlie is a Senior Principal and the Director of Civil Engineering with Walter P Moore’s Infrastructure group in Houston, Texas. He is also one of 13 people who have been with the firm for more than 30 years.