Doable Technology - How to prepare Jalkund

A simple and low-cost rainwater harvesting structure named Jalkund has been developed for storing rainwater in upper terrace conditions of this region. The different steps for preparing Jalkund and use of materials are as follows.

Step 1

Excavation of the kund on selected site is to be completed before onset of monsoon. The bed and sides of the kund are to be leveled by removing rocks, stones or other projections, which otherwise might damage the lining material. Spraying of insecticide like endosulphon 35EC on surface of the inner walls and bottom and application of aluminum Phosphide @1 tablet /live hole around 5m of the kund are to be done before lining.

Step 2

The inner walls including bottom of the kund are to be properly smoothened by plastering with mixture of clay and cow dung in the ratio of 5:1.

Step 3

After clay plastering, about 3-5 cm thick cushioning is to be done with locally and easily available dry pine leaf @ 2 to 3 kg/m2 on the walls and bottom to avoid any kind of damage to the lining material from any sharp or conical gravel etc.

Step 4

It is followed by laying down of 250 m LDPE black agri-film. The agri-film sheet is to be laid down in the kund in such a way that it touches the bottom and walls loosely and uniformly and stretched out to a width of about 50 cm all around the length and width of the kund. About 25 x 25 cm trench is to be dug all around the kund and 25 cm outer edge of agri-film is to be buried in the soil so that the film is tightly bound from all around.

Step 5

Jalkund is needed to be covered with thatch (5 – 8 cm thick) made of locally available bamboo and grasses. Use of thatch reduce evaporation up to 80 % in comparison to the control Jalkund without any cover.

Diversified use of Jalkund water

Economic Viability

	Particulars	Year
		0	1	2	3	4	5	6	7	8
A.	Fixed cost	6820	0	0	4500	0	0	4500	0	0

B	Variable cost	1400	1400	1400	1400	1400	1400	1400	1400

D	Total Cost (A+B)	6820	1400	1400	5900	1400	1400	5900	1400	1400

E	Gross return	0	4800	4800	4800	4800	4800	4800	4800	4800

F	Net Return	-6820	3400	3400	-1100	3400	3400	-1100	3400	3400

Note: Internal Rate of Return (IRR) is 31 %, Net Present Value (NPV) Rs 4096 and Benefit Cost Ratio 1.6