Alvito – Pisão Channel

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 Project (Sistema Primário de Rega do Empreendimento de Fins Múltiplos de Alqueva), provides for the completion of contracts 1º, 2º and 3º for the Stretches of the Canal Alvito – Pisão, located in the District of Beja, municipalities of Alvito and Cuba which extends some 20.17 km from the Alvito Reservoir Water Inlet to the ER5/West Cuba Reservoir.

The project comprised of three consecutive stretches with the following layout:

- Section 1: Barragem do Alvito – Circuito Hidráulico de Barras/Odivelas;

- Section 2: Circuito Hidráulico de Barras/Odivelas – Adutor da Vidigueira;

- Section 3: Adutor da Vidigueira – Reservatório Cuba-Oeste (R1);

Including the following principle infrastructure:

- Nine trapezoidal section stretches of channel 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.