Structure or weir provided across the river or creek to raise its water level and divert

the water into the main canal to facilitate irrigation by gravity

Amount of water used in producing crops which is the sum of evapotranspiration or consumptive use plus seepage and percolation losses

Rate of evapotranspiration of a disease-free crop growing in a large field (one or more

ha) under optimal soil conditions, including sufficient water and fertilizer and

achieving full production potential of that crop under the given growing environment;

Sequence of different crops grown in regular order on any particular field or fields

Any barrier constructed to store water

Volume below the intake structure; sediment volume based on 25 years of accumulation in the reservoir

Numerical value on the uniformity of application for agricultural irrigation systems

The total quantity of water diverted from a stream, lake, or reservoir, or removed from the ground in order to irrigate a crop.

Ratio of the particle size at 60% passing to that at 10% passing

Rainfall pattern with five wet months of more than 200 mm/month, five dry months of less than 100 mm/month, two transition months of 100mm200mm/month and total annual rainfall above 1500 mm.

Deposits of clay, silt, sand, gravel, or other particulate material that has been deposited by a stream or other body of running water in a streambed, on a flood plain, on a delta, or at the base of a mountain.

Substrate particles that are smaller than boulders and larger than gravels, and are generally 64-256 mm in diameter. Can be further classified as small and large cobble.

A unit used to measure water flow.

It is equal to 449 gallons per minute.

Removing material (usually sediments) from wetlands or waterways, usually to make them deeper and wider.

Migrating between main rivers and tributaries. Of or pertaining to streams or rivers.

A section of stream that has little or no turbulence.

Referring to the source of a stream or river.

Ratio of flow area to the wetted top width.

Geological formation shaped by the dissolution of a layer or layers of soluble bedrock,

usually carbonate rocks such as limestone or dolomite

Amount of water required in lowland rice production which includes water losses through evaporation, seepage and percolation and land soaking

Profile of the free water surface.

Deep percolation of water beyond the root zone of plants, resulting in loss of salts or nutrients.

Measure of the variability of discharge of a random sample of a given make, model and size of emitter, as provided by the manufacturer and before any field operations or aging has taken place determined through a discharge test of a sample of 50 emitters under a set pressure at 200 0C

The notch excavated into the side of a gully or stream to anchor a check dam or other structure.

Upper surface of saturation in an embankment

Metal or concrete bars located in the waterway across the upstream end of a conduit or spillway channel to prevent the entry of floating or submerged debris.

Basic type of Small Farm Reservoir that was only designed for flat areas. A reservoir is constructed by excavating the earth leaving storage space that can be filled with water. Water is stored below the ground level and pumping is required to draw out water.

The winding of a stream channel, usually in an erodible alluvial valley. A series of sine-generated curves characterized by curved flow and alternating banks and shoals.

A stationary or clearly identifiable source of a large individual water or air pollution emission, generally of an industrial nature

The ratio of surface area or length of pools to the surface area or length of riffles in a given stream reach; frequently expressed as a relative percentage of each category. Used to describe fish habitat rearing quality

The mass of roots associated with a tree adjacent to or in a stream that provides refuge for fish and other aquatic life.

A circular plate, generally about 10-12 in (25.4-30.5 cm) in diameter, used to measure the transparency or clarity of water by noting the greatest depth at which it can be visually detected. Its primary use is in the study of lakes.

Water that contains low concentrations of multivalent cations, such as calcium and magnesium. This type of water does not precipitate soaps and detergents.

Dam component which prevents migration of small particles and screen off fine materials that flow with seepage water and prevent piping

Ideal site for the Small Water Impounding system is that the soil shall be well-graded and shall contain at least

On selecting a site for Small Water Impounding System , It shall have a maximum slope of:

Particle diameter corresponding to a 10% sieve passing

Methods used for well characterization and site

investigation that uses the introcution of a small shock at the earth’s surface from the impact of a heavy instrument or by a small explosive charge, the time required for the resulting sound to travel to a known distance is then measured; these measurements are used to identify the type of geologic materials in the site and whether these are favorable or not for test drilling

Constructed by the cutting action of a downward-directed steam of water to excavate the hole and carry the excavated materials out of the hole.

Used in unconsolidated formations with shallow water tables that contain not too many rocks.

Type of surface irrigation where water is applied to the basin through a gap in the perimeter dike or adjacent ditch

The maximum water flow velocity into the basin shall be less than or equal to ______ to avoid scouring and erosion.

Irrigation water is supplied to the highest terrace, and then

allowed to flow to a lower terrace and so on.

DESIGN CRITERIA FOR BORDER IRRIGATION

The soil shall have a moderately low to moderately high intake rate which is mm/hr to mm/hr.

This type of furrow irrigation shall increase the length that the water must travel to reach the end of irrigation run thus, reducing the average slope and velocity

of the water.

The minimum recommended clearance between the road and culvert for railroad and road crossing is m while for farm road and thresher crossing is m if needed.

If the elevation difference is more than 5 m, an shall be used.

Safety margin to prevent overtopping of canal banks

QUANTITY OF TREATED WASTEWATER FOR IRRIGATION

shall be greater that the irrigation requirement.