riverdee CATCHMENT MANAGEMENT PLAN FD 4. FLOW EXTREMES BACKGROUND High river levels cause flood damage to property, leaving behind deposits of flood debris to be cleared up. Low river levels affect the ecological condition of the river. Water temperatures rise unusually high in summer; static pools stagnate; fish migration is inhibited. May also affect the distribution of mussels with some marginal sites becoming unviable as they become exposed more regularly Water abstraction is permitted regardless of low river levels. Spate flows cause scour this can damage the river banks, and river bed disrupting salmon redds and mussel beds, affecting river banks, groynes, bridges and other river infrastructure. Low flows reduce oxygenation and allow debris to accumulate. Thus, extremes of flow are potentially damaging. Climate change predictions indicate that North East Scotland will experience less snow but more rainfall and increased storminess in the future leading to more extremes of flow, more regularly. ISSUES Societal and industrial change and the demand for greater agricultural production have increased the catchment drainage requirement and reduced the capacity of natural flood plain storage. Improvements to land drainage and river canalization have increased the speed of flow. Peak flows downstream have thereby been increased. Property is now at risk from fluvial flooding. Infrastructure is at risk from scour damage. River ecology is at risk from low flows. Extremes of flow appear to be more likely in the future. CURRENT ACTIONS A demonstration scheme to re-introduce flood plain storage has been carried out. Schemes to re-create flood plain storage are being designed. SUGGESTED ACTIONS Implement schemes to create flood plain storage. Implement schemes to attenuate surface water run-off before entering the watercourse. Implement schemes to re-create wetlands. Relate the rate of water abstraction to river flow. (See also AB1) CONTRIBUTING SECTORS SUGGESTED PARTNER ORGANISATIONS Aberdeenshire Council, SNH, Scottish Water, Land Owners, FCS, SEPA, SERAD. LEGISLATION Action Existing/ New Legislation 4.1 FP&LD (Sc) Act 1997 4.2 4.3 4.4. 4.5 4.6 4.7 4.8 Seek to get a duty to co-operate established FP&LD (Sc) Act 1997 FP Act 1961 FP&LD (Sc) Act 1997 FP Act 1961 Forestry Act T&CP (Sc) Act 1997 NPPG7 SPPG7 FP&LD (Sc) Act 1997 4.9 4.10 FP&LD (Sc) Act 1997 4.11 4.12 4.13 4.14 4.15 4.16 FP&LD (Sc) Act 1997 FP&LD (Sc) Act 1997 FP&LD (Sc) Act 1997 WEWS? BEST PRACTICE GUIDELINES LINKS TO OTHER PLANS FLOODING AND DRAINAGE 106739660 13/02/2016 5:43 AM Page 1 of 3 MANAGEMENT OBJECTIVE FD 4. Seek to manage extremes of flow within the catchment by ameliorating run-off and providing storage within the catchment. ACTION NUMBER FD 4.1 ACTIONS PARTNERS Minimise the risk of flooding. DELETE? LA FCS SEERAD Land Owners Tarland Initiative, LA Flood Prevention Scheme for Tarland Burn Use Tarland Burn as a demonstration project FD 4.2 Identify and remedy poorly designed hill tracks LA Land Owners SNH Seek SE (or other) funding to facilitate FD4.3 Introduce ponding and controlled flooding to reduce runoff rates and prevent serious flood problems. LA SEPA SNH SEERAD Undertake a programme of talks to Community Councils etc Produce & circulate explanatory pamphlets Put articles in the P&J etc Develop an incentive scheme FD4.4 Take a holistic approach in collaboration with other agencies and stakeholders to achieve optimum solutions. LA / CNPA SEPA SNH DDSFB SW All agencies to sign a partnership agreement to collaborate FD4.5 Initiate demonstration projects LA SEPA SNH SW FC Land Owners Tarland Burn Initiative, Tarland Burn FP Scheme Seek SE (or other) funding to facilitate FD4.6 Identify areas within the functional flood plain which with the agreement of land owners and users could be managed to receive and retain flood water temporarily LA Land Owners SNH FC FD4.7 DP8? Ensure proposed land use changes such as further afforestation, moorland drainage, agricultural and urban development are assessed for their potential impact on surface and groundwater resources and do not result in more rapid run-off into the receiving watercourse or reduce the storage capacity of the functional flood plain. Competent authority FCS (forestry) SEERAD (agricultural) LA (urban) Landowners Persuade lead agencies to adopt this policy at a high priority level FD4.8 DP8? Change forest management practices to avoid clear felling adjacent to watercourses, thereby retaining a buffer against soil erosion and sedimentation of water courses. FCS Land Owners LA FLOODING AND DRAINAGE 106739660 13/02/2016 5:43 AM Page 2 of 3 ACTION NUMBER ACTIONS PARTNERS Seek SE (or other) funding to facilitate FD4.9 Restore drained wetlands within forest areas as contribution to open space provision and to reduce water runoff FCS SNH Seek SE (or other) funding to facilitate FCS Water Guidelines FD4.10 Create retention/attenuation strips by contour planting of tree belts at the base of hillsides FCS Land Owners SEERAD LA Seek SE (or other) funding to facilitate FD4.11 Assess field & forest drains in catchment for contribution to water runoff Reword FD4.12 Retrofit drainage networks on new planting and restructuring schemes to comply with current FCS water guidelines FCS Landowners SEERAD FCS SEPA Seek SE (or other) funding to facilitate FCS Water Guidelines FD4.13 Adopt contour ploughing generally in agricultural operations to reduce runoff and soil erosion. Limited to slopes < 1 in 5 ( 11° ) SEERAD Land Owners LA Initiate demonstration projects FD4.14 Create filter strips by leaving untouched buffer strips and contourploughed uncropped strips within field margins adjacent to watercourses. Limited to slopes < 1 in 5 ( 11° ) SEERAD Land Owners SNH LA Seek SE (or other) funding to facilitate FD4.15 Restore natural storage capacity of agricultural wetlands and peatlands by blocking or restoring artificial drainage where appropriate SEERAD Land Owners SNH LA Seek SE (or other) funding to facilitate FD4.16 Retain water in upland catchments by promoting good muir burn & hill grazing practice SEERAD / SNH Land Owners Liaise with CEH SNH muirburn code FURTHER INFORMATION FLOODING AND DRAINAGE 106739660 13/02/2016 5:43 AM Page 3 of 3