Metric · draft
A measurable indicator (students often call it a KPI) used as evidence for a design decision.
| Category | Water |
| Unit | % vs. baseline |
| How it is calculated | (Runoff before − runoff after) ÷ runoff before. Runoff = runoff coefficient × design rainfall × area, summed over surface types. |
| Origin | student |
| Status | draft |
Also known as: Runoff reduction ratio · Peak stormwater flow reduction · Stormwater absorption on roof · Environmental performance improvement
What it measures
How much less rainwater leaves the site after the design — the main flood-risk lever.
Calculation
(Runoff before − runoff after) ÷ runoff before. Runoff = runoff coefficient × design rainfall × area, summed over surface types.
Connections
- Used in case studies: Adam Večeřa, Aycha Chambashala, Ece Yasar, Hynek Hrabík
- Tools that can calculate it: Rainflow-Sim
- Informs decisions on: Stormwater and sealed surfaces on logistics sites
Something wrong or missing? Suggest a correction