Is Green Infrastructure Enough?

Replacing open space and forested areas with moderate to high-density development and then using green infrastructure (GI) will not mitigate the damage to water resources . While GI is a critical tool for managing stormwater, it cannot fully replicate the comprehensive hydrological functions of mature, natural ecosystems like forests. 

Replacing forests and open spaces with impervious surfaces fundamentally alters the natural water cycle, leading to increased runoff, reduced groundwater recharge, and higher pollutant loads. Green infrastructure can help manage these impacts, but preserving existing natural landscapes is considered the most effective and economical way to protect water resources. This is why the Rural Crescent was an essential element of a sustainable region.

Comparing Natural Landscapes, Development, and Green Infrastructure

Key Considerations

• Preservation First: The most effective approach to protecting water resources is to preserve natural open spaces, forests, and wetlands in the first place. Development should be directed toward areas with less ecological value.
• GI as a Mitigation Tool, Not a Replacement: Green infrastructure is essential for making developed areas more sustainable and resilient. It effectively lessens the negative impacts of development by mimicking natural processes, but it does not eliminate them entirely. It is a critical tool for mitigation, not a 1-to-1 replacement for a natural landscape.
• The Role of High-Density Development: Paradoxically, when development is necessary, higher-density, compact development can be better for regional water quality than low-density sprawl. This is because it consumes less land overall, allowing more extensive natural areas to be preserved. Integrating GI into this compact development is a key strategy for smart growth.
• Limitations of Green Infrastructure: The effectiveness of GI can be limited by factors such as space constraints in dense urban areas, soil conditions, maintenance requirements, and initial costs. Furthermore, some GI designs may not be suitable for infiltrating water if there is a risk of mobilizing existing ground contaminants