Sensitivity of peak flow response to imperviousness increase in a tropical Caribbean ungauged urban catchment

ABSTRACT

This study explores the impact of urban densification on peak flow response in an urban catchment. The catchment runoff potential grew up to 33% for the case of the runoff coefficient and 12% for the curve number due to the increase of effective impervious areas (EIA) of up to 93%, which caused the peak flow to double (101%) in some cases. Results also indicated that in highly disturbed catchments: (a) the catchment response is very sensitive even among low-return-period storms; (b) the lack of urban planning exacerbates the impact of imperviousness on peak flow increase as it promotes, among others, the presence of large EIA; (c) the values of percentage of imperviousness causing peak flow increase both vary with rainfall intensity and show a non-linear behavior; and (d) an increase in EIA of 9% seems to be the starting point of peak flow growth. The findings of this study not only outline the importance of more studies in areas with urban sprawl for the understanding of the interaction between catchment imperviousness and peak flow increase at a local level but also serve as an input for the improvement of integrated urban planning, considering the effects of urbanization in stormwater management.

KEYWORDS:

• Stormwater management
• imperviousness
• peak flow
• low return period storms
• urban sprawl
• flooding

Acknowledgements

The authors express no acknowledgement.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability

Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.

Supplementary material

Supplemental data for this article can be accessed https://doi.org/10.1080/1573062X.2022.2044864