Alvito – Pisão Canal

Beja, Portugal

Client

EDIA, Empresa de Desenvolvimento e Infra-estruturas do Alqueva, S.A.

Location

Beja, Portugal

Date

2006 - 2008

Status

Completed

The project, integrated into the Alqueva Multi-purpose Primary Irrigation System, comprised the construction of Sections 1, 2 and 3 of the Alvito–Pisão Canal, located in the district of Beja, within the municipalities of Alvito and Cuba. The canal extends from the Water Intake at the Alvito Reservoir to the ER 5 / Cuba-West Reservoir, over a total length of approximately 20.17 km.

The project comprised three consecutive sections, arranged as follows:

- Section 1: Alvito Dam – Barras/Odivelas Hydraulic System;

- Section 2: Barras/Odivelas Hydraulic System – Vidigueira Conveyance Pipeline;

- Section 3: Vidigueira Conveyance Pipeline – Cuba-West Reservoir (R1);

It included the following main infrastructure elements:

- Nine canal sections with a trapezoidal cross-section, with a total length of 18,702 m;

- Three stretches of covered rectangular section built in cut and cover style with a central septum and a total extension of 265 m;

- Three syphon stretches comprising of three lines of reinforced concrete pipe with a DN 2500 steel core over a total length of 1,365 m;

The longitudinal incline of the channel at free surface is constant and equal to 0,196m/km. The incline of the lateral slopes of the trapezoidal channel is 1V/1,3H.

The project also covered the construction of various complementary structures:

- Water inlet on the Alvito dam;

- Diversion for the Barras – Odivelas system;

- Diversion for the Cuba – Vidigueira pipeline;

- Diversion for the R1 (Cuba Oeste) reservoir;

- Control structures;

- Emergency discharges;

- Hydrological passageways;

- Upper passageways for people, vehicles and animals;

- Salvage and access ways to the channel;

- Passageways for fauna;

- Service, closure and gateways.