Understanding Low Impact Development (LID): A Sustainable Approach to Stormwater Management

Welcome back to Clear Creek Solutions’ hydrology education series. In this article, we’ll explore the concept of Low Impact Development (LID), how it helps protect the environment, and the role it plays in the future of sustainable urban design.

What Is Low Impact Development?

Low Impact Development (LID) is an environmentally friendly approach to managing stormwater. It combines green infrastructure with stormwater control strategies, emphasizing natural features to maintain water quality and support local ecosystems.

The goal of LID is to mimic natural hydrological processes. Rather than relying solely on traditional concrete infrastructure, LID incorporates elements such as vegetation, soils, and natural drainage patterns to manage runoff where it falls.

Components of LID

LID integrates a variety of design techniques and facilities. These typically fall into two categories: mechanical and biological.

Mechanical Components

• Flow control structures

• Detention and retention basins

• Outlet and weir systems

These focus primarily on controlling the volume and timing of water flow during and after storm events.

Biological Components

• Bioretention cells

• Rain gardens

• Infiltration swales

• Green roofs

These natural systems emphasize filtration, infiltration, and evapotranspiration, cleaning the water while integrating aesthetically into the environment.

Key Benefits of LID

1. Stormwater Quality Management

LID designs help filter pollutants from runoff before it reaches local water bodies. Techniques like rain gardens and bioretention allow water to soak into the soil, where natural microbial processes help break down contaminants.

2. Flow Control and Flood Mitigation

By promoting infiltration and on-site storage, LID reduces the volume and speed of runoff, helping to prevent flooding and erosion downstream.

3. Environmental and Community Benefits

LID supports green space preservation, urban beautification, and improved air quality. Features like green roofs and landscaped rain gardens also provide habitat for wildlife and cooling effects in urban areas.

Common LID Techniques

Green Roofs

These are vegetated layers installed on rooftops. They absorb rainfall, provide insulation, and reduce urban heat island effects. Green roofs can temporarily store water and gradually release it to other treatment or infiltration systems.

Rain Gardens

Rain gardens are shallow, landscaped basins that collect and filter runoff from impervious surfaces like roofs or driveways. They're typically planted with grasses and flowering plants, offering both functional and aesthetic benefits.

Bioretention Facilities

These systems use layers of soil and mulch to filter and slow runoff. They may include an underdrain system to manage excess water depending on the site's soil characteristics.

Greenways and LID Landscapes

Designed for larger-scale integration, these include natural corridors, tree-lined pathways, and buffer zones that help manage runoff while enhancing recreational and ecological value.

Why LID Matters

LID is not just about managing water during storms. It also addresses what happens between events. Through long-term infiltration, evapotranspiration, and pre-treatment, LID ensures that water is handled in a way that reduces pollution and maintains a healthy hydrologic cycle.

In fact, in the U.S. alone, an estimated $11 billion is currently being invested in green infrastructure and LID initiatives. This growing focus reflects an increasing recognition of LID’s role in sustainable development and climate resilience.

Final Thoughts

Low Impact Development provides a holistic, scalable approach to stormwater management. It emphasizes:

• Conservation of vegetation and soils

• Runoff direction toward infiltration

• Small-scale, distributed controls

• Pollution prevention at the source

By designing with nature instead of against it, LID not only protects our waterways but also makes our communities more livable, sustainable, and resilient.

For more information, including in-depth videos and modeling guides, check out Clear Creek Solutions’ YouTube channel. Thanks for learning with us—see you next time!