The trust said: “Newhaven sits adjacent to Beachy Head West MCZ, and we remain concerned about potential impacts on this protected area.
“Our preferred option is a new offshore disposal site, well away from the MCZ.”
The trust said that Newhaven was already used for dredge disposal by Newhaven Port, and there was currently no available data on the impacts of additional disposal there.
Until it saw further evidence, it did not have a view on whether Newhaven was suitable, it added.
“We will respond to any future licence application based on the ecological evidence it contains,” it said.
Brighton Marina hopes to submit a marine licence application to the Marine Management Organisation in November.
If approved, maintenance dredging could restart next spring.
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