NEYYAR IRRIGATION PROJECT



Salient Features

1.General

State

Kerala

District

Thiruvananthapuram

Taluk/Village

Neyyattinkara

gt;

Latitude

8o 32rsquo;N

Longitude

77o 09rsquo;E

River

Neyyar

2. Structural Features of Dam

Type Straight Gravity Type- masonry

dam

Top width

7.54 m

Bottom width

30.02 m

Length

295 m

Maximum height from bed level

56m

Slope- upstream amp; downstream

3. Hydrologic features of dam

Catchment area

140 sq. km

Probable Maximum Flood

809.4 Cumecs

Method of estimating PMF

4.Spillway

Location

Middle of masonry dam

Type

Ogee

Total Length

34.60 m

Crest Level

79.55 m

Design Capacity of spillway

809.4Cumecs

Number, type and size of gates

4, Radial Type, 8.69 X 5.18 m

5.Reservoir Features

Top bank level

85.645 m

Maximum water level

84.75 m

Full reservoir level

84.75 m

Maximum drawdown level

65.00 m

Dead storage capacity

10.52 Mm3

Gross storage capacity

106.25 Mm3

Freeboard over FRL

Freeboard over MWL

Area of reservoir at FRL

6.Head Sluice

Sill level

LBC +59.70 m, RBC +56.65 m