A detailed Environmental Assessment will be carried out. This will include: •Consultations and Scoping which will be agreed with all the relevant environmental bodies. •Up to 2 years of offshore field work to provide data on all aspects followed by: •Detailed modelling and assessment of the predicted effects, both negative and positive •Proposed mitigation measures and •Measures to satisfy Biological Net Gain and Marine Net Gain. Environmental Effects & Proposed Mitigation Fish •Fish data collection: Advised by Dr Clarke of Swansea University, Fishtek and regulatory authorities •Consider the use of turbines with variable speed - blades turn slower when the flow is less, lessening the risk of fish impact. •Include Acoustic Fish Deterrent to turbines. •Consider benefits of strobe lights. •Many large sluices open for about 1 hour hour every tide. •Remove certain weirs, provide fish / eel passes at other weirs especially on local streams. •Provide new salt marsh for spawning habitat. •Artificial reefs for fish and conger eels. Birds •Seek advice from RSPB and regulatory authorities. •Advised by Somerset Ornithological Society. •Birds locally are mostly passage migrants. •At present birds are disturbed by dogs and walkers on the coast path/beach. •Different time of low water in the sea and in the basin should provide greater bird inter-tidal bird feeding time. •Proposal to provide two new refuge/nesting islands in the lagoon safe from dogs and foxes. •Consider use of any spare dredged material to form intertidal habitat. •Possible new wetland/salt marsh. Siltation •Existing high silt load is high at spring tides and mostly deposited during neap tides. •3D modelling will be carried out, advised by Emeritus Professor Falconer of Cardiff University. •Lagoon water depth in general is 10m to 15m below chart datum (15m to 20m below mean sea level). The main silt deposition seems likely to be in this deeper water. •A dredger is included in operation costs to remove any excessive silt deposition within the lagoon. The lock is large enough to allow the dredger to access the lagoon. Water Quality •Collection of data on existing water quality. •Collection of data on existing sewage treatment facilities and effluent quality. •Modelling of dispersion of effluent plumes. •Consider if any new sewage treatment or longer discharge pipelines are needed.