The Project - my first week

Put bluntly, the first week was slow. Much of it was getting set up and settled in, and waiting for the Natural England equipment to come through so that I could work.

But a visit from representatives of the Severn Rivers Trust helped me to get acquainted with the project.

Our Hoveton Great Broad Lake Restoration Project is partly funded by LIFE (the EU’s funding instrument for the environment and climate action, click link for more information) and they are very keen on their different projects visiting each other and sharing experiences. The Severn Rivers Trust is planning a LIFE funded restoration project on the River Severn, as you may have guessed, and by pure good fortune their visit coincided with my first week so I was able to tag along and learn about the project alongside them.

The Broads cover an area of marshes and wet woodlands in Norfolk fed by the Yare, Bure and Waveney rivers. Hoveton Great Broad, and it's close neighbour Salhouse Broad, sit in the Bure River floodplain, which unusually for a river is in the middle of its journey to the sea and not at the bottom.

When intensive farming practices took off in the surrounding farmland, nutrients from the fertilisers on the fields fed into the Bure River, which in turn fed into Hoveton Great Broad. This influx of nutrients ending up in the Broad may sound beneficial, however it resulted in the death of all aquatic plants and the silting up of the broad by the process of Eutrophication.

This process starts with algal blooms. Simple organisms, algae are very fast growing and easily take advantage of the excess nutrients to grow into large colonies that float on the surface of the water, shading everything underneath. Without light the submerged plants can't photosynthesize and die out, their organic matter contributes significantly to the soil on the waterbed and make the Broad very shallow - in some places Hoveton Great Broad is only 30cm deep! And so we're left with a Broad void of life, while fish such as perch and bream, and birds like coot do still visit the broad there is very little of value for them there.

The Hoveton Great Broad Lake Restoration Project aims to initially remove the sediment, deepening the Broad to about 1.1m on average and reuse this sediment in Geotubing to reconstruct land habitat around the edge of the lake, based off of old maps of the area. But while the deeper lake will be a better habitat aquatic plants won't be able to grow as long as the algae stays dominant.

The second phase of the project is biomanipulation; removal of the fish from the broad. This may sound a little unfair to the fish to be barred from a habitat but this will give the water fleas, or Daphnia, a chance to multiply without their natural predators. The Common Water Flea feeds on the algae and naturally they would keep the algae in check by their grazing while fish species prevent overgrazing by preying on the Daphnia. But at Hoveton Great Broad the unnatural nutrient levels have caused an imbalance which Natural England hopes to fix by a temporary, controlled imbalance in the other direction.

After 30 years of sewage treatment and altered farming practices the Bure River has been cleaned so that now is a perfect time to restore the Broad and the Hoveton Great Broad Restoration Project has begun sediment removal this season, for more information please click the link.