Innovative geotextile bag technology helps restore reed bed at Salhouse Broad

In east-central England, geotextile bags are filled with river sediment to restore eroded riverbank

Reports from the U.K. describe how huge woven geotextile bags—8.5m wide with a circumference of 18.6m—are filled with dredged sediment to help restore a reed bed as it was in 1946.

The bags are filled with 3,000m³ of sediment dredged from the River Bure to provide a 170m retaining bank at Salhouse Broad (broad—Brit: “an expansion of a river”).

Erosion during the last 60 years from boat wash and wind caused the land between Salhouse Broad and the River Bure to narrow down to 2m in places, threatening the integrity of the riverbank and its riverside mooring.

Now 7,000m² of reed bed is constructed using four giant geotextile bags, which have been fixed to alder poles cut from riverbanks near Salhouse Broad.

Sediment from two nearby dredging sites at Wroxham Broad and Decoy Broad is carried to Salhouse by barge where it is unloaded into a pump by an excavator. The pump, conventionally used for concrete, fills the geotextile bags via a pipeline.

The surface of the geotextile bags is planted with reed seed and rhizomes taken from encroaching reed fringes in the river to help restore it as a natural reed bed.

Source: Dredging Today