Water stress is rapidly turning in to water crisis. Water availability on the earth remains the same as it was 5000 years ago when mankind population was just 5 million as against present population of 7700 million. However, “there is enough water for everyone’s need but not enough for anyone’s greed”, as pointed out by Gandhiji who was also not in favour of “putting too much burden on the resources (including water) provided to us by nature”.
The present scenario of water stress is more acute because of three “Mis” – Misallocation, Mispricing and Mismanagement of water than actual shortage in term of water availability.
For that, it has now become inescapable but to adopt a two-pronged strategy, consisting of supply with augmentation/ enhancement of water availability through internal measures on one hand and demand management on the other. Such internal measures can be categorized in to (i) Collective, (ii) Managerial and (iii) Statutory.
Collective measures
Rainwater harvesting has the maximum potential to augment or enhance the water availability. All types of buildings, namely, domestic, commercial and industrial as well as existing and new buildings / under construction should have appropriate rainwater harvesting system and for that, adequate incentives including statutes should be considered. Another option for augmentation of availability is to rejuvenate and modernize the existing water bodies, namely ponds, stepwells, lakes and rivulets.
Most of them are today almost in disuse due to encroachment and filling up by garbage and other waste materials. Such programmes can be more effective if it is propelled by public participation. Long distance water transportation should be the last option and purely as a supplemental measure.
According to a research by the Stanford University, runoff (surface flow) caused by the rainfall or precipitation can result into groundwater recharge to the extent of maximum 9% when there is no external intervention on ground. But, in case of external intervention on ground, like check-dam, recharge wells, bandharas etc., the groundwater recharge by surface runoff can be maximized up to 30%. As of now, we are harnessing just 8% of the total rainfall / precipitation which is 4,000 billion cubic meter per year in the country.
According to an estimate, 10 years ago, there were about 15000 small and medium rivers in the country of which about 4500 i.e. 30% have now been seasonal, that is, flowing only during the monsoon season.
Our water use efficiency is one of the lowest in the world, mainly because we treat water as a consumable good rather than an economic input
Renowned environmentalist, naturalist and thinker, Henry David Thoreau (1870-1962) said: “A lake is a landscape’s most beautiful and expensive feature. This earth’s eye; looking into which the beholder measures the depth of his own nature”.
Managerial measures
Water management by municipal corporations and municipalities is today quite worrisome and a matter of serious concern. The average water use efficiency is about 35-40%. Water loss, which is now being termed as non-revenue water, is just 5 to 6% in public water distribution system in Singapore.
All leakage sources/points in public water distribution systems as managed by municipal corporations and municipalities need to be first detected and then with due rectification it should be regularly monitored. This requires a “leakage detection and monitoring system” to be set up in all big (metro) cities to begin with.
In the wake of fast growing demand of water especially for big cities, desalination plants are being now installed in cities like Chennai. In Gujarat, eight desalination plants with aggregate capacity of 390 MLD located in seven districts of Saurashtra and Kuchchh are being set up at the estimated cost of Rs 4,000 crore.
In Israel, 80% of the water for drinking is obtained from desalination plants and the desalination technology has been upgraded from time to time with the result that its cost has now come down to just one third of the cost that was 20 years ago.
Brine, which is a very poisonous chemical and is 1.5 times of the desalinated water, hugely absorbs oxygen as present in the seawater and thereby seriously endangers the marine life and the eco-system. Therefore, the option of desalination should be exercised with due care and caution.
Statutory measures
Flow irrigation in which water is flown in canal/channel to irrigate crops is an agricultural practice that had begun five thousand years ago. We need to modify our irrigation network system in order to make it adaptable for use of micro-irrigation, i.e. sprinkler and drip irrigation.
Before going for desalination plants on a large scale, we need to know that the desalination technology is not totally benign technology
Paddy and sugarcane are two main water-guzzling crops, which require very large quantity of water consumption. Necessary policy measures including food grain procurement policy and appropriate Subsidy Mechanism need to be taken to disincentivise such water guzzling crops.
The need of the hour is to enhance irrigation water use efficiency from its present level of 40% to atleast 65-70%. In Israel, this water use efficiency is around 90%. In this regard, water theft from irrigation canal should be strictly stopped. In addition, wastewater, after due process of recycling, should be used for irrigation.
In Israel, about 80% of the wastewater is reused after recycling out of which about one third is used for irrigation. Necessary statutory measures as well as motivation and promotion of farmers’ participation need to be taken up in form of a campaign or public awareness programme because the share of irrigation in total water use accounts for 80%.
Saving water by about 20% from irrigation use, would release/spare water, which would be adequate to meet with our water demand for drinking purpose.
We need to have judicious sense for water use on one hand and establish as well as enforce the accountability for water managers through water accounting and auditing system along with proper water pricing on the other. Water pricing should be such that it conveys the scarcity value of water. Gandhiji was known to optimally use the resources available to him and to keep meticulous record of their uses.
Our water use efficiency is one of the lowest in the world, mainly because we treat water as a consumable good rather than an economic input. In developed countries, the water use efficiency is linked with the water productivity according to which the revenue generated by using the unit of water is calculated. Water use efficiency (in terms of water productivity measured in USD/M3) are 281, 85, 21.2 and 16.7 for UK, Singapore, Brazil and China respectively where as it is just 1.9 USD/m3 for India.
Metropolitan cities of the world which are moving quickly towards Day Zero are Cape Town (SA), Bengaluru (India), Islamabad/Karachi (Pakistan), Beijing (China), Nairobi (Kenya), Mexico City (Mexico), Sao Paulo (Brazil), Istanbul (Turkey) etc.
*Former secretary to Government of India
Courtesy: https://www.counterview.net/