Nature cannot take more abuse. Hence the degradation caused to the environment of the city has to respond in terms of its wrath. Floods in Delhi are not natures wrong doing, it is invariably the irresponsibility of the authorities and those who are to tally insensitive of human life blinded by the economics of haves and have nots. This is very clear from the recurring phenomenon of floods in the mighty river Yamuna and flash floods caused by rains due to choked drains of Delhi.
River Yamuna
Keeping in view the topography, Yamuna catchments upto Delhi is divided in two parts - (1) The upper catchment from source in Himalayas to Kalanaur in Haryana - which com[rises parts of Himachal Pradesh and hills of West Uttar Pradesh and (2) the lower catchment from Kalanaur to odl Delhi rail bridge which consists of West Uttar Pradesh and Haryana.
River Yamuna enters Delhi from the northeast near Palla at an altitude of 210.3 meters and after traverse of about 40km. it leaves Delhi at an altitude of 198.12 m near Jaitpur in the Souht. The width of the riverbed varied from 1.5 to 2.0km. in its flow from Wazirabad barrage, a network of seventeen drains joins the river on the West bank during its traverse in the northern parts of the city. Najafgarh and Alipur drains, due to heavy discharge from Sahibi river, inundate a number of villages in Nazafargarh block causing heavy damage to life and property. There was, however, little effect of it in Yamuna river flow. Only one drain joins on the East bank near the old rail bridge.
Past Data on Floods
| S.No. |
Date |
Gauge (mm) |
| 1. |
28.5.63 |
205.40 |
| 2. |
28.9.64 |
205.64 |
| 3. |
15.8.66 |
205.85 |
| 4. |
19.7.67 |
206.19 |
| 5. |
9.8.67 |
205.27 |
| 6. |
16.8.69 |
204.89 |
| 7. |
10.8.71 |
206.28 |
| 8. |
18.7.72 |
205.00 |
| 9. |
29.7.73 |
205.50 |
| 10. |
7.8.74 |
205.15 |
| 11. |
12.9.75 |
206.00 |
| 12. |
12.8.76 |
206.70 |
| 13. |
7.8.77 |
205.85 |
| 14. |
6.9.78 |
207.49 |
| 15. |
16,7,80 |
205.55 |
| 16. |
5.8.81 |
204.90 |
| 17. |
13.8.83 |
205.80 |
| 18. |
12.10.85 |
205.20 |
| 19. |
27.9.88 |
206.92 |
| 20. |
20.8.89 |
205.67 |
| 21. |
5.8.90 |
205.02 |
| 22. |
19.8.92 |
205.40 |
| 23. |
24.7.93 |
205.06 |
| 24. |
26.8.94 |
205.36 |
| 25. |
8.9.95 |
206.93 |
Table 1 floods in Delhi (source : Irrigation and Floods Control Deptt.)
The flow of Yamuna within Delhi is by and large influenced by discharge from Tajewala Headwork 240 kms upstream. In the event of heavy rain in the catchment area excess water is released from Tajewala. Depending upon the river flow level down stream, it takes about 48 hours for Yamuna level in Delhi to rise. The rise in water level also causes backflow effect on the city's drains. The city also experiences floods due to its network of 18 major drains having catchment areas extending beyond the city's limits.