FLETCHING MILL WEIR:
Mr R A Draper
Date: 27 November 2008
Dear Mr Draper
Moving towards more sustainable management at Fletching Mill
Thank you for your letter dated the 20th October and for the time you have taken in preparing your detailed comments representing the views of the Sussex Ouse Restoration Trust. We have recorded your views within the consultation record that we have been maintaining throughout the Fletching Mill Feasibility Study and will take all consultee comments into account as part of the decision-making process regarding future management of the river and structures at Fletching Mill.
In the meantime, we felt your detailed submission merits a considered response, given in particular some of the issues and assertions raised. The comments detailed below are referenced to the numbered sections in your letter to enable the corresponding responses to be identified.
With regard to the history of the site (section 1) you state that “the pound above Fletching Mill weir has been at its present level for over three hundred years”. This is not technically accurate taking into account the drop in water levels that was experienced following the failure between the sluices failing in 2001 and the installation of temporary works in 2002.
Regarding recent events in 2001 (section 2) I can confirm that it was in fact the newly installed replacement gates that were damaged at the time of the “straw bale” collecting at this point rendering them inoperable. Subject to this damage there was no temporary works carried out to re-instate the pounding upstream of the site until 2002.
In reference to consultation leaflet (para 3a), the main purpose of issuing this to key stakeholders in March 2008 was to identify key stakeholder concerns and issues at the outset of the Feasibility Study, in order to inform the option appraisal process rather than to define what options were being proposed. The leaflet therefore stated that “Solutions being considered at this location include: modification of the weir at the head of the by-pass channel and regrading of the by-pass channel”. This implies that these were not the only option under consideration as, at this early stage, we were still determining baseline conditions and the range of options for consideration. We accept that our consultation leaflet could have made it clearer that crushing of the weir in situ was an option, although “modification of the weir” could plainly include this outcome.
We received the report prepared by Mr Sutton (para 3b) in April 2008 and agree with the substantive points of fact presented regarding the condition of the weir structure. Points in the report of relevance to the SORTs subsequent position include the following. (Para 1.5) “The Sussex Ouse Restoration Trust proposes to restore the Sussex Ouse to navigation. This report is prepared at their request to advise on options that might assist both navigation restoration and the preservation of historic structures...”(Para 3.2)” Regarding and introducing of riffles [in the by-pass channel] would improve the ecological potential of the present poor environment”. With regard to the proposed consideration of diverting the flow from the by-wash channel (termed by the Environment Agency as the mill channel), we can confirm that we have included consideration of this option in our Feasibility Study.
With regard to the public consultation meeting at Fletching Village Hall on 8th September 2008 (para 3c), we agree on the whole with the record of events you describe but would differ on points of fact.
With respect to comments concerning the ecology of the surrounding land (section 4) as a result of the proposed solution, we feel your assertions significantly exaggerate the risks. The area immediately upstream of Fletching Mill has been a floodplain since far before impoundment took place at the site and will continue to be a floodplain after the weir is removed. It is unreasonable to state that “this land will be permanently drained, destroying its fragile ecosystem” and there is no evidence to suggest this will happen. We have already consulted with Natural England regarding the habitats upstream of the weir and they do not see this as a constraint on our proposals.
With regards the requirement for a “full Environmental Impact Assessment” (section 4), each project the Environment Agency undertakes undergoes a screening process to judge the level of Environmental Impact Assessment (EIA) required, using a risk-based approach above and beyond statutory requirements. The Agency’s National Environment Assessment Service has been involved in this project from the outset and the project has been screened as not requiring full statutory EIA. However, we have identified key environmental risks and commissioned a series of specialist surveys as part of our EIA process.
You will be aware that reducing flood risk (section 5) is a key goal in our Corporate Strategy. Nationally, with limited funding available for flood risk management projects, streamlining the management of individual assets is particularly important to making the best use of available resources. In this case, removing the requirement for re-construction and future maintenance of Fletching Mill weir is inline with this goal. Locally, flood risk is critical to the viability of any project at the waters edge and a detailed computer mathematical model has been built to simulate the effects of weir removal on water levels. Results show that flood risk is only locally affected, with a reduction in water level observable for less than 1 km upstream of the site. Catchment scale management is vital to achieving reduced flood risk in critical and flood prone areas like Lewes. The River Ouse Catchment Flood Management Plan defines and justifies strategic policies for different areas and the area around Fletching Mill is defined by a policy to increase flood risk. Whilst this project will locally reduce flood risk, it is being considered in conjunction with a number of local schemes, including reinstating old meanders cut-off from main river channel through historic navigational improvements. When combined these projects will align with strategic catchment objectives and also bring the river into a more natural ecological state.
Contrary to your comments concerning the ecology of the river (section 6), our study indicates that the proposed solution will in fact result in greater biodiversity and this is a key driver for the project. The proposals being discussed would restore river connectivity and a more natural flow regime within the river, in line with European legislation (in particular The Water Framework Directive), and the Environment Agency policies on sustainability, river restoration, flood risk management and biodiversity commitments. A report on options at Fletching Mill prepared by the River Restoration Centre (2002) also states that, under a low water regime: “The water flow regime will be much more dynamic than the previous still water ponded regime. The habitat diversity sustained by the new regime should be much greater than previous”. With regard to the requirements for a detailed species survey, the need for detailed surveys would routinely be identified as part of ongoing EIA process that would continue through further stages of this project.
With respect to comments regarding the effect on fishing (section 7) the fact that there may be barriers to fish movement downstream does not negate the value of improving fish passage at the Mill. Otters are unlikely to be constrained by the proposed solution and are particularly dependent on adequate riparian vegetation, i which will not be affected by the proposed solution. With respect to otters, Sussex * Biodiversity notes that “Structures installed into waterways to control water levels, such as weirs, mills and locks often restrict the movement of this species”.
At face value , flood risk and ecology are central to your arguments and we feel that evidence and submissions from flood risk specialists and professional ecologists contradict your points in these areas. With respect to restoration of the Ouse Navigation and preservation of historic structures-issues not mentioned in your submission but clearly at the heart of SORT’S opposition to this scheme - we share your concern about preservation of historic structures but are not in a position to contribute to your aims to restore navigation to the Ouse.
I hope this letter has clarified the points you have raised.
cc: Ms Joanna Eyquem, Royal Haskoning,