The chair of Bembridge Harbour Trust, Jeremy Gully, has said that a sandbank could develop right in the middle of the harbour within as little as 15 years if the siltation continues at its current rate.
Dredging is promised to start again in Bembridge Harbour on 1st April 2020. If this happens it will be good news for the harbour, as many areas have not been dredged for a number of years and urgently need attention to simply allow boats to continue to use the Harbour.
But Jeremey Gully has questioned whether it will be sufficient enough to halt the Harbour’s rapid siltation. He says that if things continue at the current rate, in as little as 15 years we could see a sandbank showing in the middle of the harbour even at high tide, right where boats currently sail.
Mr Gully told the annual general meeting (AGM) of Bembridge Habour Trust last month that the conclusion of the analysis of the latest LiDAR survey data – a sophisticated kind of aerial survey – supports this.
Jeremey has said:
“The equivalent of four 10 tonne truck loads of sand from the sea and silt from the river settle in the harbour daily. Yet over the last seven years, only an average half a truck load a day has been dredged from inside the harbour.
“A 2009 public report by the Environment Agency and the Isle of Wight Council had already warned about this trend – similarly based on survey evidence.
“However, the latest LiDAR data reveals the quantities and distribution of material entering the harbour over a 20 year period. Now, we can differentiate between silt and sand, allowing us to have some idea of how much of the build-up is coming from the river and how much from the sea. The worrying conclusion is that the rate at which the harbour is filling up has accelerated.
“With a much clearer picture of the problem, we can start to talk with confidence about causes and, most importantly, possible solutions. Bembridge Harbour Trust has already made numerous positive suggestions, actively supported and raised money for the groyne project and could even help to raise financial help for other projects if needed”.
The full siltation report is available on the Bembridge Harbour Trust Website at http://bembridgeharbourtrust.org/wp-content/uploads/2020/01/Rates-of-accretion-revision-3-05.01.2020.pdf.