Project Details
In-water works will be undertaken from June to September (inclusive) as agreed with NatureScot. As such, the works are programmed to begin on 1st of June 2026 and last up to 4 months, utilising the whole approved works window. The works will be undertaken during daytime working hours, with in-water works underta
Description
BEAR Scotland has been commissioned by Transport Scotland to carry out full refurbishment of the A9 Mound Sluices structure.
The A9 Mound Sluices is a structure located parallel to the A9 carriageway bridge, constructed to separate the River Fleet from the sea. The structure was built by Thomas Telford and consists of six masonry arches, each containing two wooden sluice gates to make twelve gates in total. Two winch houses and a small storage building are present adjacent to the bridge. The sluice gates prevent the ingress of sea water at high tide and allow fresh water from the River Fleet to flow out as the tide falls.
Refurbishment works on the structure started in 2021, with the refurbishment of four gates (arches 1-2), repointing of the structure and repair works to both winch houses. In 2025, a concrete apron slab downstream of arches 4-6 was reinforced to create a temporary dry-working area during periods of low tide. Works in 2025 also included the installation of a new galvanised/ stainless steel access ladder to the upstream north wing wall; the installation of angle steelwork for stop board (logs) to the upstream entrances of arches 3-6; and repairs and refurbishment of the winch houses and storage building.
Works in 2026 will involve the gate and pointing refurbishment to arches 3 to 6. This involves the replacement of all timberworks to arches 3 to 6; and the repointing of the external faces and the arch (3-6) internal faces. A maximum of two arches will be closed at any one time, with arches 3-4 completed first, followed by arches 5-6. The proposed works will involve in-water works and will utilise the concrete apron slabs on both upstream and downstream sides of the sluices.
The proposed refurbishment works have been condensed, with all four remaining arches (3-6) planned to be completed in 2026 (as opposed to two in 2026 and two in 2027). This is due to the poor condition of the arches and concerns that the gates could fail leading to the potential for significant flooding issues upstream. The proposal to refurbish the four remaining arches in 2026 has been approved by NatureScot.
ken during the low tide. The site compound will be situated in the Highland Council car park located to the west of the A9 Mound Sluices structure with no requirement for traffic management (TM) on the A9. It is anticipated that the car park will be closed to allow for material storage and welfare compound, following approval from Highland Council. Access to residential properties north of the sluices will be maintained.
Location
The scheme is located adjacent to the A9 carriageway at the mouth of the River Fleet, 5.3km south of Golspie in the Highland Council Local Authority area (Figure 1). The National Grid Reference (NGR) for the centre point of the sluices is NH 77544 98217.