1 An economic assessment of the amenity benefits associated with alternative coastal defence options. Dr Mike Christie and Oliver Colman University of Wales Aberystwyth

2 Current coastal defence Wooden groynes – now at end of their useful life Seawall Shingle bank

3 New ‘traditional’ coastal defence options for Borth  Replace wooden groynes  Rock groynes  Raise height of seawall

4 An alternative coastal defence option: multi-purpose reef

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6 Research aim and method  Aim: To examine local residents AMENITY values for alternative coastal defence options.  Method: Choice experiments

7 Choice experiment attributes and levels  Visual Appearance No change No change Rock Groynes Rock Groynes Offshore Reef Offshore Reef  Seawall No change No change Raised wall Raised wall  Surf Conditions No change No change Improved Improved  Conditions for Family Beach Activities No change No change Safer conditions Safer conditions  Increased taxation 6 levels 6 levels

8 Choice task: Borth example OPTION AOPTION BSTATUS QUO Visual appearanceStructures made from large rocks would replace the timber groynes. Existing timber groynes with shingle bank Height of seawallNo change in the height of the wall Wall raised by 1 metre to reduce the likelihood of overflow No change in the height of the wall Surf conditionsConditions for surfing would remain unchanged Conditions for surfing would improve Conditions for surfing would remain unchanged Beach conditions for family amenity Safer conditions for beach activities Conditions for beach activities would remain unchanged Annual tax increaseYou will pay an extra £15.00 tax annually over a 5 year period You will pay an extra £6.00 tax annually over a 5 year period Your tax bill will not be increased Choice A [ ] B [ ] SQ [ ]

9 Results: RPL model Non random parameters in utility function  ASC_SQ * (-7.851)  Visual_rock_groyne * (-6.002)  Visual_reef 0.746* (7.381)  Family_amenity 0.495* (4.399)  Tax * (-4.839) Random parameters in utility function  Seawall (0.987)  Improved_surf (-0.181) Heterogeneity in Mean, parameter : variable  Seawall_Upper * (-1.884)  Surf_surfer 1.116* (3.387) LL model LL constants only Pseudo-R Correct predictions0.462

10 Results: Implicit prices AttributesRPL Visual_timber_groynes (all residents) -£19.82 * (7.23) Visual_rock_groyne (all residents) -£28.66 * (8.06) Visual_reef (all residents) £48.49 * (12.84) Seawall (all residents) £19.81 (20.12) Seawall (Upper Borth only) -£45.45 * (30.49) Improved_surf (all residents) -£1.95 (10.85) Improved surf (Surfers only) £70.59 * (21.02) Family_amenity (all residents) £32.14 * (10.09)

11 Key observations  Visual timber groyne: negative  Visual rock groyne: negative  Visual reef: positive  Family amenity: positive

12 Key observations  ‘Seawall’ and ‘improved surf were insignificant  Seawall – Upper Borth interaction is significant: Lower Borth want generally want sea wall Lower Borth want generally want sea wall Upper Borth don’t. Upper Borth don’t.  Improved surf – Surfer interaction is significant: Surf conditions now significant for surfers, who want improved surf Surf conditions now significant for surfers, who want improved surf Non-surfers still insignificant Non-surfers still insignificant

13 Amenity value associated with coastal protection proposals at Borth Coastal defence optionCompensating surplus value (£ per household) Replace existing groynes with timber groynes 0 Replace existing groynes with rock groynes Replace existing groynes with a multi-purpose reef (excluding surf improvements) 98.5 Replace existing groynes with a multi-purpose reef (including surf improvements)

14 Conclusions  The multi-purpose reef option provides significant amenity benefits over traditional coastal defence options.  Mixed views with regard to raising the seawall.  Policy makers should consider non-market values in coastal defence proposals in the future.

15 Thank you for your attention. Any Questions