Measuring performance of low impact development practices for the surface runoff management

Area of Science:

• Environmental Engineering
• Hydrology
• Urban Planning

Background:

• Urbanization increases impervious surfaces, leading to higher stormwater runoff.
• Low Impact Development (LID) offers a sustainable approach to manage surface runoff.
• Assessing LID performance requires long-term hydrological analysis and cost-effectiveness evaluation.

Purpose of the Study:

• To analyze the long-term performance and cost-effectiveness of various LID practices for stormwater runoff management.
• To evaluate the impact of precipitation scenario duration and LID implementation schemes on runoff mitigation.
• To provide guidance for selecting appropriate LID practices in urban environments.

Main Methods:

• Conducted a long-term hydrological modeling study (2001-2015) using the Storm Water Management Model (SWMM).
• Simulated seven different LID practices under six precipitation scenarios.
• Performed a cost-effectiveness analysis based on life-cycle costs and runoff removal rates.

Main Results:

• LID practices significantly reduced surface runoff, with performance influenced by scenario length and implementation.
• The combination of infiltration trench, permeable pavement, and rain barrel (IT+PP+RB) achieved the highest runoff removal rate (23.2%-27.4%).
• The rain barrel alone was the most cost-effective LID option (C/E ratio: 0.34-0.41).

Conclusions:

• Long-term hydrological simulations provide a more accurate assessment of LID performance than short-term studies.
• The effectiveness of LID practices stabilizes after a 1-year simulation period.
• The study offers valuable insights for urban planners and decision-makers on implementing effective and economical LID strategies.