How do you access Gurgaon’s water information?
Topo sheets (Topographical sheets) are digitalised – you can see it on onemapgurugram. The wet infrastructure section on that gives the entire water information on the watershed areas.
In Gurugram, on the basis of digital elevation, there are certain sinking points. There will always be a low-lying area where water accumulates. For a large area or a micro study of a watershed area, assess the first and second order of water channels – and do your analysis on the basis of that.
For example, if you are studying the Wazirabad bund micro-watershed area, study the sinking points, the accumulation points, the outlets and the capacity of the region. Settlement areas have a different capacity from the unpaved regions, where the run-off infiltrates the soil. Since the city was not hard-topped earlier, the sinks were different.
Has the soak capacity over time been recorded anywhere?
You have to do a digital analysis. We use satellite imagery of the earlier times when it was agricultural land. We have satellite imagery from 1975 till date. If it was unpaved agricultural area, forest area, wasteland, the Sahibi river or the lake that was in the Ghata area. We call it Leg 1 and it drains into the Najafgarh lake. There are underground pipes near Khandsa and below the National Highway which takes the water efficiently into the Najafgarh lake.
How many natural creeks are there in Gurugram?
There were four channels with creeks earlier. Creeks are actually the areas where rivers drain into the sea where there is a backwash as in the Sundarbans at the mouth of the Ganga. Here we have nullahs, trails, trawls, sub-stream or tributaries. But because in the documentation we have been referring to them as creeks, we continue with that even now.
In Gurugram’s administrative boundary there are four of these trails. One is the Park area. Second is Sikandarpur, third is the Smriti Vatika area and the fourth is Ghata. Multiple streams feed into that. Different channels from the Aravalis drain into these creeks. Channels are not created as a one-time process. As rain falls the water makes different channels naturally. There can be multiple water inlets. But they all accumulate in the low lying areas. But when encroachment or development takes place, all these channels get broken and that water floods the city roads.
Is there an impact assessment study on barriers in the water channel and what can be done to overcome them?
A comprehensive study has not been done yet.
Where large societies have come up, they cannot be removed. It can be made to seep in if we make separate rainwater harvesting structures in each and every building. From inception it has to be planned what to do with the processed water in the society, how water gets reused through the channel. For instance, they need water for horticulture, for car wash etc. Every building can plan their waste water usage through the Residents Welfare Association.
In plotted sectors, the water planning can still be done retrospectively. If there is a road with a green belt on the sides with pedestrian areas, water channels can be placed below the pedestrian areas.
How do you study how the water logging can be reduced?
Use the satellite imagery to study this area – irrigation plan, the agriculture plan, district maps and topo sheets . Now it has all become red with the expansion of the city. In topo sheets settlement areas such as the Wazirabad village area are visible. When sectors were planned, unplanned colonies and the slum areas came up alongside.
We have to see the slope of the land. You have to look at multiple parameters such as the catchment of a sector. How much water accumulates in the catchment and whether it comes from surface run-offs or the stand-off. If there is a dumping site, that can absorb the water. But is there a drainage system there? A working sewage system? Layout plans about where the water comes from and if it is still working or choked with debris.
Are there Standard Operating Procedures for this?
There is a 70 degree natural slope in Gurugram. When water encounters a barrier, it does not flow, and the ground becomes slushy.
There is water coming down from the mountains. But the Golf Course Road interrupts the water channel. Drainage channels have been placed below the road. Check dams have been made. The Wazirabad ecorestoration project and lake are now in fully working condition. One small portion is still encroached. If the channels are provided then this becomes a reservoir for all that water. Water is channelised in the upper stream too because the green belts are available and can be linked to the pondage area.
The railway station parking was originally a pond. The pond authority of Haryana is currently restoring ponds that had been marked in old maps. In the Ghata and Southern Peripheral Road the space is there to channel the water but it is encroached and cleaning too does not take place. The good news is that there is a possibility of revival.
How can Gurugram use its natural gradients to manage water?
The natural slope of Gurgaon from Aravali Hills to Najafgarh lake is approximately 75-80 metres. There are gradients of 2-3 metres even between sectors. That is a good slope. In natural conditions, water would never stand at all in the city but would automatically drain out.