The final scheme to be delivered by Moray Flood Alleviation is the Forres (River Findhorn & Pilmuir) FAS. Situated by the River Findhorn, Forres has historically suffered from flooding from the river. The Pilmuir area has also suffered predominantly due to poor drainage and high ground water levels.
This £45million scheme involves the construction of a 5km long embankment up to 3m high set back from the river together with extensive works close to the river channel to create space for higher flows. Two roads are being raised to pass over the embankment and a 66 year old footbridge across the Findhorn has been extended by 90m to travel over the lowered river bend. Works within the watercourse itself have been limited in order to avoid negative impacts to habitat.
Material excavated from the river bends is sorted and processed on site to produce fill material for the flood embankments, road sub-base and access tracks.
Surface water flooding in the Pilmuir area is addressed by the construction of open drainage channels, augmented with pumping that operates to push the water over the embankment when the river is in spate. The fully automated pumping system comprises three variable speed vertical impeller axial flow pumps each rated at 1.1 cubic metres per second. The pumping station design is optimised for maximum reliability and availability.
Construction started in September 2012 and the scheme is currently due to complete by the end of 2014, two months ahead of programme. Natural river processes will inevitably mean that the river bends will accrete over time, reducing the effectiveness of the Scheme. On completion of the scheme the Council will be provided with a monitoring plan linked to trigger levels for intervention allowing them to maintain the space created for water.