Rainwater Harvesting Techniques Quiz

Observing the surface flow helps ensure that the tank is positioned to effectively collect rainwater while maintaining natural water flow patterns.

Factors include the local rainfall pattern, the extent of land to be cultivated, and the investment available for construction.

A circular shape is recommended because it can withstand greater pressures from the stored water.

<p>The tank should not exceed 1.75 meters in depth to withstand water pressure and facilitate easier cleaning and maintenance.</p> Signup and view all the answers

<p>A fence serves as a safety measure to prevent children and negligent adults from accidentally falling into the tank.</p> Signup and view all the answers

<p>If the tank obstructs natural water flow, it can lead to soil erosion, which can damage crops in the area.</p> Signup and view all the answers

<p>Positioning the tank's opening towards the rainfall flow ensures efficient water collection and reduces the risk of obstructions.</p> Signup and view all the answers

<p>Siting land close to a wadi is crucial because it provides access to floodwater, which is essential for crop or fodder production in arid areas.</p> Signup and view all the answers

<p>Bunds for slopes of less than 0.5% are straight, open-ended structures placed 50 meters apart, designed to slow and spread floodwater, with a recommended height of 60 cm.</p> Signup and view all the answers

<p>The short upslope wing in graded bunds helps intercept floodwater flow from the upper bund, thereby further checking and spreading the flow down the slope.</p> Signup and view all the answers

<p>The recommended maximum dimensions are a height of 60 cm, a base width of 4.1 meters, a top width of 50 cm, and a maximum length of 100 meters.</p> Signup and view all the answers

<p>Harvested water can be stored in cisterns, tanks/jars, or ponds/reservoirs, primarily for domestic use and gardening.</p> Signup and view all the answers

<p>As the radius of the tank increases, the capacity also increases.</p> Signup and view all the answers

<p>The slope of the tank should be about one foot from the periphery to the middle.</p> Signup and view all the answers

<p>The bricks should have dimensions of 5 cm × 10 cm × 23 cm.</p> Signup and view all the answers

<p>The ratio of sand, cement, and gravel in the concrete mixture should be 1:2:4.</p> Signup and view all the answers

<p>This ensures that the water can flow into the tank without obstruction.</p> Signup and view all the answers

<p>The concrete slab should measure 0.75 m in height.</p> Signup and view all the answers

<p>Mud filters should be placed around the water inlet door to reduce waste items entering the tank.</p> Signup and view all the answers

<p>The brick bunds should be in the shape of a ‘V’.</p> Signup and view all the answers

<p>The ratio of cement to sand should be 4:1.</p> Signup and view all the answers

<p>The small bunds should be constructed at 45 cm and 85 cm from the inlet.</p> Signup and view all the answers

<p>The closer small bund should be 0.75 cm lower than the inlet bund.</p> Signup and view all the answers

<p>This design allows for the retention of waste items in silting chambers within the bunds.</p> Signup and view all the answers

<p>The spill space should be 1.25 cm higher than the inlet-door.</p> Signup and view all the answers

<p>The tank should be plastered about 15 cm above ground level.</p> Signup and view all the answers

<p>The space should be filled tightly with sand because it can be packed well and resists decomposition.</p> Signup and view all the answers

<p>All soil deposits and waste products should be removed and the tank cleaned well.</p> Signup and view all the answers

<p>A small thatched hut and fence can be constructed around the tank.</p> Signup and view all the answers

<p>If maintained properly, the tank can be used for about 15 years.</p> Signup and view all the answers

<p>The external bund should be constructed 0.75 cm lower than the internal bund.</p> Signup and view all the answers

<p>Water-plants increase water loss through evapotranspiration.</p> Signup and view all the answers

<p>'Korali' (Oreochromis mossambicus) can be introduced.</p> Signup and view all the answers

<p>Microcatchments, macrocatchments, floodwater harvesting, and storage.</p> Signup and view all the answers

<p>Contour bunds are more economical and suitable for cultivating crops or fodder.</p> Signup and view all the answers

<p>Contour bunds are suitable under rainfall conditions of 200–750 mm.</p> Signup and view all the answers

<p>Soils must be at least 1.5 m deep, preferably 2 m deep for adequate root development.</p> Signup and view all the answers

<p>Contour bunds are favorable for slopes from flat up to 5.0%.</p> Signup and view all the answers

<p>They may experience overtopping of excess water leading to breakage at low spots.</p> Signup and view all the answers

<p>When designed correctly, there is no loss of runoff out of the system.</p> Signup and view all the answers

<p>The topography must be even, without gullies or rills.</p> Signup and view all the answers