Option 1 - Impact Of Doing Nothing
Impact of doing nothing on the predicted Cliff Line every 10 years.
Following the collapse of the seawall, it is expected that the cliff will reprofile to a more natural angle of repose, with the cliff line moving some 15m inshore of the existing line of the seawall.
Thereafter the coast is expected to recede at the predicted annual average rate, although clearly rates will vary year by year (due to storms) and from one point to another.
Erosion of the coastline will lead to a loss of the following
- Beach
- Anglian Water sewerage works, buried behind the promenade and under Gorleston cliffs
- Pier Hotel
- Ocean Room
- Shops
- Public shelters along Lower Esplanade
- Public car park
- Public gardens
- Residential properties
Can erosion really cause that much damage?
If nothing is done the shoreline will erode, and will result in damage. Other towns such as Corton have suffered damage in the past.
Option 2 - Do the Minimum
Minimum capital expenditure
Promenade becomes progressively unusable over 10 years as its collapse becomes inevitable resulting in:-
- No beach
- Risk of failure of the seawall during a storm event, possibly leading to the exposure of the sewerage works immediately behind the seawall structure
- Beach material lost alongshore and offshore
Rebuild sections of the seawall as and when they fail, reconstruct seawall in year 10
Maintain the integrity of the defences with the minimum capital expenditure (repair on failure).
Option 3 - Annual Beach Recharge
Annual Beach Recharge from Great Yarmouth Beach and refurbish existing seawall
- Open beach with high amenity value
- Maintain the beach at a level sufficient to prevent waves breaking on the seawall and to provide more anaerobic conditions for toe piles so as to reduce the rate of corrosion.
- Recharge the beach with sand extracted from the accreting beach at South Denes, Great Yarmouth.
High capital expenditure (very large recharge quantities required)
Disruption every 5 years due to beach material transported to Gorleston beach
Beach material lost alongshore
Option 4 - Vertical Seawall
Construct a new vertical seawall in front of the existing wall.
- High amenity value of new promenade
- High capital expenditure
- No beach
- Beach material lost alongshore and offshore
Option 5 - Concrete Revetment
Concrete Revetment and Wave Return Wall
- Open beach with high amenity value
- High capital expenditure
- Beach material lost alongshore and offshore
- Large recharge quantities required
The lower wall and existing rock toe protection will be stabilised and protected with a revetment constructed from pre-cast concrete armour units
Well what do you know ?
These are the options presented by Halcrow for consideration by Great Yarmouth Borough Council. For some reason, only known to themselves, Councillors were reluctant to impart this information so that many residents were unable to come to an informed opinion regarding the Gorleston Sea Wall.
We always believe honesty is the best policy. Unfortunately not a word in any politicians vocabulary.