Detection and visualization of storm hydrograph changes under urbanization: an impulse response approach.

Area of Science:

• Hydrology
• Environmental Engineering
• Urban Planning

Background:

• Urbanization significantly alters natural hydrological processes, impacting storm responses and leading to environmental and engineering challenges.
• Effective management of urbanized catchments requires rapid identification of development-induced changes in storm hydrographs.
• Existing methods may be resource-intensive or lack intuitive accessibility for stakeholders.

Purpose of the Study:

• To propose a pragmatic, low-cost method for assessing and monitoring urbanization-induced alterations in watershed storm responses.
• To provide tools for intuitive and rapid identification of changes in internal watershed dynamics.
• To integrate existing concepts for accessible environmental monitoring and management.

Main Methods:

• Calibrating rainfall-runoff time-series models across successive time windows representing varying urbanization levels.
• Utilizing only precipitation and stream discharge or stage data for model calibration.
• Employing unit impulse response functions from time-series models for a visual and intuitive representation of hydrograph changes.

Main Results:

• The proposed method generates empirical response functions that capture storm hydrograph alterations as they occur.
• Assessments of hydrograph changes are independent of variations in meteorological forcing.
• A preliminary application using a low-order linear ARX model demonstrates the technique's potential.

Conclusions:

• The developed technique offers a fresh perspective and potential advantages for watershed management compared to existing approaches.
• The method provides a mathematically formal yet visually accessible representation of watershed storm response changes.
• Further research and testing are necessary before practical implementation as an environmental management technique.