Abstract
Urban groundwater recharge with rainwater is of great significance for increasing urban groundwater resources and alleviating water-logging problems. The rooftop rainwater has good water quality and high pressure head. It can be collected and treated rapidly and then recharged into the groundwater under pressure without external power demand and without occupying extra space area. However, this proposed concept is still under research. Therefore, this study took the New Campus of Tianjin University as the research site to perform calculations and assess potentials for this rainfall utilization mode. The semi-empirical formula was developed from field test data of groundwater recharge under pump pressure. The realistic parameter values were selected in the calculations. The design rainfall intensity of different rainfall recurrence intervals and durations was calculated by using the rainstorm formula for Tianjin, and the rainwater replenishment rate was quantified for this rainfall utilization mode at the study site under different design conditions. The quantification results show that the replenishment rate is positively correlated with the rooftop rainwater detention time. Assuming the rooftop rainwater detention time 24h, the rainwater recharge rate is greater than 90% for rainfall smaller than the 25-year storm; and for the rainstorms with recurrence interval of 50 or 100 year, the rainwater recharge rate is over 85%. This study demonstrates that this rainwater utilization mode has a high application value and can serve as a reference for research on technologies for the groundwater recharge with rainwater.
| Translated title of the contribution | Concept and assessment of utilizing rooftop rainwater for pressurized groundwater recharge |
|---|---|
| Original language | Chinese (Traditional) |
| Pages (from-to) | 999-1009 |
| Number of pages | 11 |
| Journal | Shuili Xuebao/Journal of Hydraulic Engineering |
| Volume | 50 |
| Issue number | 8 |
| DOIs | |
| State | Published - Aug 1 2019 |
ASJC Scopus subject areas
- Water Science and Technology
- Energy Engineering and Power Technology
- Mechanical Engineering
Keywords
- Detention time
- Pressurized groundwater recharge
- Rainfall duration
- Rainwater recharge rate
- Rooftop rainwater