River Garnock

Introduction

The smallest of Ayrshire's six principal rivers, the Garnock's source is in the Muirshiel Hills above Kilbirnie. From here it flows for 39km before entering the sea, via a shared estuary with the River Irvine. Although it has a catchment area of 238km2, similar to the River Girvan, the Garnock itself is a relatively small river as its largest tributary, the Lugton Water, meets the Garnock below the tidal limit. Principal land uses in the catchment area are agriculture, moorland and urban development. The most significant land use, forming 74% of the total, is improved or good rough grassland, much of which is intensively grazed. There is a relatively low level of forest cover (6.9%) in the Garnock catchment compared to rivers such as the Stinchar.

The Garnock flows through three large towns, Kilbirnie, Dalry and Kilwinning. Water management within the catchment is currently under review in the River Garnock catchment flood defence strategy.

The fishery on the River Garnock is managed by the angling clubs based in the three towns along the course of the river. The West Strathclyde Protection Order 1988 means that it is an offence to fish for freshwater fish within parts of the Garnock catchment without written permission.

Caaf Water waterfall	Kilwinning Cauld
culvert on the Paduff Burn	Garnock Spout

Key features

• With a catchment area of 238km², The Garnock is the smallest of the six principal rivers in Ayrshire.
• Rises in the Muirshiel Hills above Kilbirnie from where it flows for 39km before entering the sea via the shared estuary with the River Irvine.
• Many water supply reservoirs constructed in the hills on the west side of the catchment. Caaf Water receives a compensation flow of 3.4Mlitres/day from the Camphill Reservoir (check).
• Water supply abstraction point on the main River Garnock upstream of Kilbirnie, which has the potential to impact on flows downstream.
• No sewage treatment work’s on the main River Garnock as all sewage pumped to the coast for treatment at Irvine plant
• Major tributaries are the Rye Water, Caaf Water, Bombo burn, Dusk Water and Lugton Water.
• River flows through the centres of the following major urban centres: Kilbirnie, Dalry and Kilwinning.
• Catchment suffers from many weirs and culverts which block or hinder passage of migratory fish.
• Lugton water is the largest tributary with a catchment of 54km².
• Lugton flows for 27km from Libo loch to join the Garnock at Kilwinning, downstream of the tidal limit.
• Water quality in the Lugton is degraded due to influence of sewage and agricultural run-off.
• Common fish species present include salmon, trout, eels, stone loach, minnows, sticklebacks, lampreys. Roach were also recorded in the upper Lugton Water during 2006 electrofishing survey.
• Several stillwaters within the catchment are operated as coarse fisheries, increasing the risk of establishment of alien species within river habitat.

Ayrshire Rivers Trust research and monitoring on the River Garnock includes:

• A catchment wide Habitat survey was completed 2005, with funding from North Ayrshire Council, Scottish Natural Heritage and the Garnock Angling Clubs. The Habitat Survey recorded many significant obstructions to fish migration ranging from fallen trees to impassable culverts and weirs. Pollution points and areas of habitat degradation were also recorded.
• Electrofishing surveys were carried out in 2003, 2005 and 2006 to investigate fish populations throughout the catchment.
• Invertebrate surveying was carried out in 2005 and 2006 to investigate water quality.