THE DON DISTRICT SALMON FISHERY BOARD RIVER DON DRAFT GRAVEL MANAGEMENT PLAN NEWE DAM

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1 THE DON DISTRICT SALMON FISHERY BOARD RIVER DON DRAFT GRAVEL MANAGEMENT PLAN NEWE DAM

2 Introduction The Newe Dam at Strathdon is situated on the upper reaches of the river Don catchment area, Grid Reference NJ During flood conditions large amounts of gravel and sediment collect behind the weir, which can cause several problems, i.e. restricting movement through the fish pass, restricting the movement of fish above the weir once ascending the fish pass, and possibly giving false readings to the Q90 hands off flow for the Newe Macro Hydro scheme abstraction point, which is situated directly above the weir on the North Bank (see Cover Photo) In previous years a local contractor would remove the gravel allowing the fish to move freely above the weir upon leaving the fish pass. Map below shows the location of the Newe Weir/Dam and grid Reference. Legal Obligations As the DDSFB are the owners of the weir and attached structures to the weir, we have a legal obligation by law to comply with The salmon (Fish Passes and Screens) (Scotland) Regulations 1994 and The water Environment (controlled Activities) (Scotland) Regulations The engineering activity falls under SEPA s guidance on Gravel Abstraction through the General Binding Rules (GBR #12) Sediment Management within 10m upstream of a weir and GBR9: Operating any vehicle, plant or equipment (machinery) when undertaking GBR activities 5, 6, 7, 8, 10, 12, 13 and 14. The DDSFB will ensure compliance with these conditions see Appendix 1.

3 Best Practices All work shall comply with current SEPA Regulations, and codes of Practice. With particular reference being paid to SEPA s Engineering in the water environment a good practice guide Sediment Management. A letter notifying SEPA of the engineering activity will be sent prior to commencement of works. General Binding Rules 9 and 12 shall be followed and adhered to explicitly. All machinery used will be power washed before going near the river. Refuelling and storage of fuels/oils/pollutants will be at a safe distance from any water course. The excavator will always be on drained gravel (hard standing) within the river, as per guidance from SEPA, given during a meeting at the Newe Dam in A member of the DDSFB staff will be on site at all times during operations. Prior notification of works commencing will be given to Mr John Riley Owner of the Newe Macro Hydro scheme. The gravel will be extracted at least twice a year. This will be dependent on gravel movement, due to large increases of river levels throughout the year. Method Statement Operations and timing for the gravel removal from the Newe Weir would be between the months of June and September during typical low flows. Before the month of June young salmon and trout will still be within the substrate. September through to the end of November is the spawning time for this part of the river system. During low flows two by-wash sluice gates, which are pictured in the centre of the image on the far bank, will be opened to divert the flow and drop the water level behind the weir. Once this has taken place an excavator will commence extracting the gravel. At all times the excavator will be on a hard stand on the gravel bar working backwards to where he first entered the channel.

4 Figure 1. Looking from the North Bank towards the fish pass and the twin sluices on the south bank. Notice the raised gravel bars in front of the fish pass. The level of gravel to be removed will be to a depth of approximately 1-2ft below the bottom lip of the fish pass as seen in Figure 2, this will allow for an adequate depth of water for fish to move safely once leaving the fish pass, and move through the fish pass with ease. Figure 2. Looking from the South bank towards the North bank with the Fish Pass on the RHS of the image and the Macro Hydro Abstraction point on the LHS of the image. Note the raised gravel bars and the proximity of these gravel bars in relation to the fish pass. This image was taken during reduced levels when the sluices were open to allow abstraction.

5 Once the required depth has been achieved, the twin sluice gates will be closed to allow for the water level to regain its natural state as illustrated in Figure 3 below. Figure 3. Typical flows exhibited above the weir crest following a previous gravel abstraction note the lack of raised gravel bars present as seen in Figures 1& 2.

6 Gravel Use In order to facilitate the replacement of sediment within the system the gravel abstracted from the Newe Weir site will be used to shore up bank repair work through out the river system below the wier. This will ensure that the gravel will find its way back into the river system during flood conditions. The gravel could also be used in other parts of the catchment during in stream habitat improvement works. All SEPA recommendations on gravel management at the Newe site will be followed. Gravel storage Facility Details Following abstraction the gravel will be taken a short distance to a temporary storage area situated at the following address. Owner of facility: Mr Stuart Milne Address: Meikle Tolly AB36 8XA Tele: Grid Reference: NJ Map of Facility Below

7 Newe Weir Ownership details. Don District Salmon Fishery Board Clerk to the Board Mr George Alpine 15 Golden Square, Aberdeen AB10 1WF Tel: Fax: The Don District Salmon Fishery Board Draft Gravel Management Plan compiled by, Mr James Kerr River Superintendent 17 Norman Gray Park Blackburn Aberdeen AB21 0ZR Tele: Mobile:

8 Appendix 1 GBR s GBR9: Operating any vehicle, plant or equipment (machinery) when undertaking GBR activities 5, 6, 7, 8, 10, 12, 13 and 14. Rules: a) Machinery should only operate in water where it is impracticable for it to operate on dry land. b) Refuelling must take place at least 10m away from any surface water. c) Any static plant or equipment used within 10m of surface water must be positioned on a suitable drip tray with capacity for 110% of the fuel tank supplying the static plant or equipment. d) Machinery used in or near surface water must not leak any oil. e) Washing of any machinery must take place at least 10m away from any surface water and the washings must not be allowed to enter any surface water. f) Machinery must not be operated in rivers, burns and ditches when fish are likely to be spawning in the affected surface water, or in the period between spawning and the subsequent emergence of juvenile fish. (If in doubt about these times, you are advised to contact your local District Salmon Fishery Board or Fishery Trust for advice). GBR12: Removal of sediment from the area of impounded water upstream of a weir authorised under CAR, and where desired, return of that sediment to the watercourse. Rules: a) Sediment or other matter can only be removed within the stretch 10m upstream of the weir. b) Only sediment which has recently been deposited (i.e. that which is reasonably expected to have been deposited within the three years preceding the date of removal) can be removed. c) Sediment that has been removed may be returned to the watercourse, provided that: it is returned within the 10m stretch downstream of the weir; it does not cause sediment to accumulate in a manner likely to impede the free passage of migratory fish; all reasonable steps are taken to avoid increased erosion of the bed or banks of the watercourse; and it is not returned during periods in which fish are likely to be spawning, nor in the period between spawning and the subsequent emergence of the juvenile fish.

9 d) The removed sediment and other matter must not be placed on the bank of any watercourse. e) The return or removal must not result in pollution of the water environment. f) Vegetation may be removed from the banks only if the works cannot otherwise be reasonably carried out. g) Vegetation that is removed must not be disposed of into the channel.