The fallacy of long-term average reservoir levels

As of 15 September, the water storage at 91 major reservoirs stood at 107.7 billion cubic metres (bcm), 16% higher than the year-ago reading.

Despite the monsoon rains being lower than earlier anticipated, the improvement in reservoir levels is seen as a bright spot. As of 15 September, the water storage at 91 major reservoirs stood at 107.7 billion cubic metres (bcm), 16% higher than the year-ago reading.

Crucially, the 10-year average storage reading rose to 92% this month compared to 77% a year ago. The improvement in reservoir levels and the long-term average reading are seen to augur well for winter crops (rabi), which are mostly river- fed.



But much is left unsaid. The storage level is only 68% of total storage capacity of the 91 reservoirs covered, which means almost one-third of the reservoir capacities are unfilled. Second, consecutive years of low reservoir level readings mean the 10-year average, based on which the long-term average is calculated, has moved far away from the actual storage capacity levels.

Data from the ministry of agriculture says the 10-year average reading as of 8 September stood at 111.8 bcm. It is only 71% of actual reservoir capacity level or the long-term averages are calculated on less than three-fourths of the reservoir capacities. The 10-year average reservoir reading till 15 September is not readily available. But the falling trend in the long-term average-down from 97% on 8 September to 92% last week-means 10-year average figures are as unreliable as the monsoon rains.

Newsletter

Price of goats has gone up due to lack of supply in Kannivadi goat market

As farmers are not keen to sell the goats at the Kannivadi goat market, the arrival of goats has come down for the last...

Tomato prices fall sharply in Udumalpet - produce indiscriminately thrown on the road

Tomato prices were sold at Rs 200 per kg a few months ago. Now that the price of tomatoes has fallen drastically due to...

Tomatoes sold at Rs 6 per kg in Palladam - Farmers put veil on their heads and express anguish

Farmers in Tirupur district are suffering as tomatoes were procured at just Rs 6 per kg at the Palladam uzhavar santhai....

TNAU's Dept. of Plant Pathology hosts one-day training on 'Spawn Production and Mushroom Cultivation' in Coimbatore

Over a 100 beneficiaries from Kongunadu Arts and Science College in Coimbatore participated in the training which was pr...

Coimbatore TNAU observes Parthenium Awareness Week

Dr.M.K.Kalarani, Director (Crop Management), TNAU, Coimbatore has inaugurated the Parthenium awareness campaign at TNAU...

TNAU conducts Training on Preparation of instant Foods

Two days training on “Preparation of instant Foods” will be held at Centre for Post Harvest Technology, Agricultural...