Evaluation of options The evaluation criteria have been applied each option, where the comparison is in relation to the other groyne options. It does not consider other protection solutions / coastal structures or scenarios. Each criterion rated on a scale from Very Low to Very High. As each criterion had a varying scale, rating have been coloured coded to convey well performing options, where green shading is a good result and red shading is a poor result. provides a summary of the evaluation while presents further context around each of the ratings provided, consider for each individual option. Table 5-2 Evaluation of Options Summary – Criterion in - Life Intertidal Risks (changing on (Design, /work Amenity Technical maintain) Communities Key Required Technical term construct, Design Environment Effectiveness Cost Effectiveness Reef long /Effects Option – LOW LOW LOW LOW LOW LOW N/A MODERATE Do Nothing Option – Extend BELOW BELOW MODERATE HIGH LOW MODERATE HIGH MODERATE existing groynes AVERAGE AVERAGE Option – VERY VERY VERY VERY ABOVE ABOVE HIGH HIGH Add additional HIGH HIGH HIGH HIGH AVERAGE AVERAGE groynes – Rock Option – BELOW BELOW ABOVE Add additional MODERATE MODERATE MODERATE MODERATE MODERATE AVERAGE AVERAGE AVERAGE groynes – Timber/Polymer Option – Combination: VERY ABOVE ABOVE Rock & Timber HIGH HIGH HIGH HIGH HIGH HIGH AVERAGE AVERAGE Groynes Option – Combination: VERY VERY VERY ABOVE VERY VERY Rock & Timber HIGH HIGH HIGH HIGH HIGH AVERAGE HIGH HIGH Groynes with Small Breakwater NB. The colour coding assigned to the rating changes due to varying rating scales for each criteria. In general, green is considered a GOOD rating, while red is considered a POOR rating.
Evaluation of options The evaluation criteria have been applied each option, where the comparison is in relation to the other groyne options. It does not consider other protection solutions / coastal structures or scenarios. Each criterion rated on a scale from Very Low to Very High. As each criterion had a varying scale, rating have been coloured coded to convey well performing options, where green shading is a good result and red shading is a poor result. provides a summary of the evaluation while presents further context around each of the ratings provided, consider for each individual option. Table 5-2 Evaluation of Options – Summary Criterion Technical Effectiveness Technical Effectiveness - long term (changing Cost (Design, construct, maintain) Environment /Effects on Intertidal Reef Communities in Required /work Design Life Amenity Key Risks Option – Do Nothing LOW LOW LOW LOW LOW LOW N/A MODERATE Option – Extend existing groynes BELOW AVERAGE BELOW AVERAGE MODERATE HIGH LOW MODERATE HIGH MODERATE Option – Add additional groynes – Rock VERY HIGH HIGH VERY HIGH VERY HIGH VERY HIGH ABOVE AVERAGE ABOVE AVERAGE HIGH Option – Add additional groynes – Timber/Polymer MODERATE MODERATE BELOW AVERAGE BELOW AVERAGE MODERATE MODERATE MODERATE ABOVE AVERAGE Option – Combination: Rock & Timber Groynes VERY HIGH ABOVE AVERAGE HIGH HIGH HIGH ABOVE AVERAGE HIGH HIGH Option – Combination: Rock & Timber Groynes with Small Breakwater VERY HIGH HIGH VERY HIGH HIGH VERY HIGH ABOVE AVERAGE VERY HIGH VERY HIGH NB. The colour coding assigned to the rating changes due to varying rating scales for each criteria. In general, green is considered a GOOD rating, while red is considered a POOR rating.
Point_Lonsdale_Groyne_investigation_-_FINAL_REPORT.docx