Making information travel faster than flood water
The first project – Hydrology 1 – focused on the peninsular states, where most rivers are straddled by a series of reservoirs (the Western Ghats in Maharashtra alone are dotted with more than 1,800 reservoirs and barrages of both large and medium sizes). The second project extended its reach to cover the two water-rich northern states of Punjab and Himachal Pradesh.
To better manage water flows from these reservoirs, new systems now monitor all the important aspects of the hydro-meteorological cycle. Measurement begins high up in the catchments of rivers, where digital gauges measure how much rain or snow has fallen, how rapidly the snow is melting, the speed with which the water is flowing, how much silt has built up, how much water will reach the reservoir, how soon it will do so, and so on. Sensors in the field instantly transmit this information to data centres through satellite or mobile phone technology, enabling managers to form a clear picture of the water situation unfolding in their region.
While these systems have been installed across peninsular India, the Bhakra Beas and the Krishna-Bhima systems have gone a step further. They now have a modelling tool that helps them predict water flows into their reservoirs three days in advance. This means that the lead time for planning the release of water from these reservoirs has shot up from just hours to days.
“Earlier it took lots of manpower and at least 24 hours to process this information from the field. Not surprisingly, engineers often ended up doing a post-mortem of a flood rather than pre-empting one,” recalls Gaur. Now, whenever it rains heavily, reservoir managers can start releasing water slowly so that the reservoirs remain full while there is no risk to dam safety and no damage downstream.
Advance information is particularly important for the shorter peninsular rivers where it barely takes a few hours for the water to travel from the catchment to the reservoir. “Sangli town in Maharashtra, for instance, used to have flash floods whenever there was a sudden release of water from the Koyna dam upstream,” Gaur adds. “Now this no longer happens.”
These reservoir management systems, which cost a total of Rs 30 crores, have helped avert flood damages of over Rs. 238 crores. And, the results are there for all to see. In 2010, for instance, Punjab, a highly flood-prone state, experienced some of the worst floods in its history, taking a huge toll on life and property. But, in 2013, when the rivers were in similar spate, no floods took place and there was no damage. This is not to say that floods will no longer happen, explains Gaur. If the rains are unduly heavy, floods may well take place, but advance warning can certainly help save lives.
These systems can also help alleviate the harshest impact of droughts. “A full reservoir is the best cushion against a drought in the dry season,” says Gaur. “Thanks to these systems, 2015 was the first time that all the Krishna basin reservoirs in Maharashtra were full by the end of the monsoon.”
With groundwater levels depleting at an alarming rate, the second project – Hydrology 2 – used advanced geophysical techniques with helicopter-borne instruments to pilot the mapping of aquifers in five states – Rajasthan, Bihar, Maharashtra, Karnataka and Tamil Nadu.
The technology is not only much faster and more accurate than other methods, but is also much cheaper. “Groundwater modeling is an extremely complex subject,” explains Gaur. “Once the mapping is complete, we will get a much clearer picture of the groundwater resources in a region. It will also help in designing the best methods to recharge and manage this precious resource.”
Closer magnification can also throw up a host of new issues. “Until now our information was on a scale of 1:250,000. Once it is reduced to 1:50,000 or better, who knows what will come to light?” Gaur adds.
Since water quality has emerged as another critical issue, the second project also helped states identify where the quality of groundwater has been affected by fluorides, nitrates, and other contaminants.
Monitoring water quality
The second hydrology project also piloted water quality monitoring in surface water sources. Thirteen real-time water quality monitoring stations were set up on the Ganga and Yamuna rivers. These stations proved extremely useful in maintaining water quality during the Kumbh Mela in 2013 when millions of people took the ritual dip in the holy river.
Real time readings from these stations helped determine when water needed to be released upstream on critical bathing days, and when it needed treatment. Today, these stations continue to play their role on both these rivers, especially upstream and downstream of the capital, Delhi. Given the usefulness of these stations, 111 more such stations are being planned along the main Ganga river.
Managing competing demands for water
The systems and technology introduced under the two hydrology projects have much broader applications too. “If we are to manage our exceedingly complex web of water resources effectively, we need to know how much water the country has, when it has it, and where it has it,” clarifies Gaur. “Without accurate data on the existing water situation in the country, we are really shooting in the dark.”
Water data can also be a critical input in making development decisions. In Pune, for example, a planned tunnel between two reservoirs to improve the city’s water supply was abandoned for a simpler, better and cheaper solution.
Accurate water data also provides a scientific basis on which to manage competing demands for river water, especially as disputes are often sparked by the lack of correct information. “Accurate data can not only guide the sharing of river waters but also be used to better manage the fragile ecology of a river basin, help with better water resources planning and allocation during lean periods, design flood protection works, and so on,” explains Chabungbam Rajagopal Singh, water resources management specialist at the World Bank in New Delhi.
A third Hydrology project, supported by the World Bank, will now expand the water resources monitoring system to cover the entire country, including the Indus, Ganga, and Brahmaputra-Barak river basins. Under this project, the Ministry of Water Resources will provide states with a grant to collect water data for each river, stream and reservoir in their territory.
The importance of sharing water data
“Importantly, we need to move beyond mere data collection to using it more effectively. For this, the willingness of organizations to open up their data and make it transparent will be the key, explains Gaur. In addition, water resources institutions will need to be brought under one umbrella with one single agency to manage both ground and surface water. Engineers and scientists will also need to evolve into water managers and take a river basin-wide approach to manage all water resources in an integrated manner. More importantly, riparian states and other stakeholders will need to come together to plan the allocation of river water during a dry year, a wet year and a year of normal rainfall, while being ready for climate change.
“Overall, the real and tangible benefits of the systems established under the two Hydrology projects include people whose lives, homes, and crops are saved due to improved flood forecasting, farmers who benefit from improved irrigation supplies, and children who do not fall ill or worse from drinking contaminated water,” said Halla Maher Qaddumi, senior water economist at the World Bank in New Delhi. “Over time, it is hoped that accurate water data will also help reduce conflict between people and states over shared water resources.”
Leaders in Transparency
· The Central Water Commission has created a state of the art platform that publicly shares national level water data online.
· Maharashtra shares real time water information together with streamflow forecasts, and audits water use by various sectors for each major/ medium reservoir. This is published annually on the web.
· Others states too are devising interim arrangements to display water information and joining the central platform on water resources information, while still others are yet to follow.
· Transparency is equally important for groundwater too. For, unlike surface water bodies which are managed by the government, the management of groundwater lies primarily in the hands of the people. Andhra Pradesh has been the first off the block in this, posting monthly bulletins and real time information on the groundwater situation on the Chief Minister’s web portal.
· Gujarat too is conducting an indepth analysis of the groundwater situation, particularly around the cities, to meet growing urban demand.
· Going forward both the centre and states will need to join hands to develop a sound national water resources information system and agree to make it accessible.