| 不透水层面积分分级 | 温度/℃ | 
| ≤10% | 33.01108 | 
| 11%~20% | 34.41853 | 
| 21%~30% | 36.58246 | 
| 31%~40% | 36.69606 | 
| 41%~50% | 39.08632 | 
| 51%~60% | 41.0614 | 
| 61%~70% | 41.26859 | 
| 71%~80% | 45.9986 | 
| 81%~90% | 46.76027 | 
| >90% | 48.16331 |