Between 2 November and 10 December 2004, a Public Inquiry heard evidence from Edinburgh Council, its engineers, and concerned members of the public regarding the proposed Water of Leith Flood Prevention Scheme (FPS).
The Inquiry was supported by a chartered civil engineer with specialist experience of flooding, and the Inquiry Report (in April 2005) attempted to give balanced and impartial recommendations. This Report was refreshingly forthright in its criticism of aspects of the FPS design.
It recommended that ‘Scottish Ministers should not confirm the Water of Leith Flood Prevention Scheme until the City of Edinburgh Council has … carried out further investigations and analysis to remedy any deficiencies in the hydrological analysis [etc.] and until any necessary adjustments have been made to the scheme arising from this additional work’.
However, in March 2007, Scottish Ministers overruled the Report's recommendations, concluding that ‘there are no defects in the … hydrological analysis [etc.] which would cause them to require their re-examination’.
Last year, the Scottish Environment Protection Agency (SEPA) re-examined the Inquiry concerns, and it now advises that new accommodation should not rely on the Water of Leith FPS. Whilst hydrology is not an exact science, the position regarding the Water of Leith FPS should be clearer than it is. There should be more agreement, less dispute.
To be fair, the Scottish Ministers gave reasons for overturning the Inquiry recommendations, and the Inquiry engineer, I imagine, would have been persuaded in many respects. He may still have requested further analysis, though, especially with respect to hydrological questions and climate change. But whilst the Council and their Engineer were involved in discussions, persuading the Scottish Executive, it is not obvious that the Inquiry team was similarly involved.
Recent Council communication has highlighted climate-change increases, which is ironic because the Inquiry was clear that ‘insufficient allowance has been made for climate change’, and suggested that the 12% allowance be doubled or more. (The Inquiry also indicated that the choice of 12% rested with the Council, for ‘[the designer was] instructed to design on the basis of a 12% increase … to allow … for climate change’.)
However, the Scottish Government ruled that ‘the allowance made for climate change is reasonable … and was based on the best available science at the time’. The italics are mine; the wording already seeming to acknowledge that the climate-change allowance was out of date. The Inquiry recommendation now seems reasonable; it is in line with the figures currently being discussed.
Hopefully, progress will be made in resolving the other (non-climate-change) concerns raised by SEPA (and the Public Inquiry). One puzzling issue may be quickly addressed: at the Inquiry, the engineers all agreed on the significance of managing the upstream reservoirs for flood reduction. In March 2007, ownership of the reservoirs passed to the Council, which was expected to facilitate management. To learn now from SEPA that the reservoirs are not being managed for flood reduction begs the questions: Were the engineers mistaken, or does the Council simply have insufficient resource to manage the reservoirs?
If reservoir management can significantly reduce the flood risk, then it's worth demanding as the cost should be relatively low.
BSc (Civil Engineering), MSc (Water Engineering)
 Water of Leith FPS Public Inquiry, Final Report, April 2005, clause 6.14.1
 Scottish Executive decision letter dated 15 March 2007, clause 17.
 See investigative report by the Broughton Spurtle (online), 10 July 2019.
 Water of Leith FPS Public Inquiry, Final Report, April 2005, clause 6.8.
 Water of Leith FPS Public Inquiry, Final Report, cl.5.26; Technical Report cl.1.51 & 52.
 Water of Leith FPS Public Inquiry, Technical Report, April 2005, clause 1.47.
 Scottish Executive decision letter dated 15 March 2007, clause 16.1.
 Water of Leith FPS Public Inquiry, Final Report, April 2005, cl.1.48, 1.145, 2.23, 5.79.