MARANHÃO DAM |
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| PURPOSE - Irrigation / Hydroelectric | |
| LOCATION | GENERAL FEATURES |
| District -
Portalegre Municipality - Avis Site - Maranhão River Basin - Tejo River - Seda river |
Promoting entity
- INAG Owner - Associação de Regantes e Beneficiários do Vale do Sorraia Engineering by - DGSH Construction by - Moniz da Maia & Vaz Guedes Project year - 1952 Year of completion - 1957 |
| HYDROLOGY | RESERVOIR |
| River basin area
- 2282 km2 Mean annual runoff - 24600 x 1000 m3 Flood runoff - 2200 m3/s Return period - 500 years |
Reservoir area
- 19600 x 1000m2 Gross capacity - 205400 x 1000m3 Effective storage - 180900 x 1000m3 Dead storage - 24500 x 1000m3 Normal water level (NWL) - 130 m Maximum flood level (MFL) - 130,9 m Minimum operating level - 111 m |
| DAM | |
| Earthfill - Zoned
embankment Height above foundation - 55 m Height above streambed - 49 m Crest elevation - 133 m Crest length - 204 m Crest width - 10 m Foundation - Schist and greywacke Volume of dam body - 592 x 1000 m3 |
|
| SPILLWAY | BOTTOM OUTLET |
| Location - Right
bank Control type - Controlled Spillway type - Shaft spillway Sill elevation - 125 m Sill length - 2 x 27 m Number of gates - 2 radial gates Maximum discharge - 1600 m3/s Energy dissipation - Hydraulic jump |
Location - Right
bank Type - Rock tunnel Section - d 1,5 m Maximum discharge - 44 m3/s Upstream control - Sluice gate Downstream control - Sluice gate Energy dissipation - Hydraulic jump |
| POWER PLANT | |
| Type - Contiguous
to the dam Number of installed units - 1 Type of units - Francis turbine Mean annual energy output - 13,1 GWh |
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