DOP Submersible dredge pumps

A DOP250 with cutter unit maintains reservoir in Malawi


Location: Tedzani Hydroelectric Power Plant, Tedzani Falls, Malawi
Period : Q3/2018 – Q1/2019
Product type : DOP250 with cutter unit
Contractor : Mota Engil Africa – Malawi branche

Vital inlet maintenance at hydropower dam

A DOP250 has been delivered for hydropower dam maintenance to Malawi. The DOP submersible dredge pump, fitted out with a cutter unit, will work at approx. -4 m dredging depth removing the layer of silt built up through time at the water inlets.

Hydropower dam job site overview

The DOP250 will start dredging from the dam itself, mounted on an excavator boom. Once the emergency dredging has finished, the excavator with DOP will be mounted on a pontoon. The pontoon will be located in the reservoir, gradually covering the entire surface.

A package delivery is a complete dredger in a number of containers including the bolts hence the buckets

The DOP is fitted out with both depth, revolutions and pressure indicators. All are safely mounted within the dredge pump’s steel casing – thus protected from the environment. Their data are collected in a box mounted on the side of the excavator. The read-out is on a practical colour screen mounted inside the cabin for an easy observation by the operator.

The crane operator monitors the DOPs speed and pressure on screen

The Tedzani hydropower dam is part of a complex of integrated hydroelectric power plants on the Shire River in Malawi. The various dams have been built over a number of decades, and continue to supply power to the national gird as they are continuously modernized and maintained.

The DOP250 with cutter unit was fixed onto the boom at the work shop

Currently a maintenance campaign of the pond, or reservoir, is ongoing. As a start, silt is removed from the dam to clean the inlets of the turbines. Moreover, the reservoir is dredged to expand its water storage capacity. To prevent a further accumulation of silt in the reservoir and near the dam, the river feeding the reservoir is diverted. The enlarged water storage results in an increased electricity induction capacity as the plant will be able to run at full capacity for a longer time during peak periods.

Starting with emergency dredging from the dam itself for hydro power dam maintenance