Location of the Fal Estuary

Major estuary systems in Cornwall - place cursor over image for more information

The Fal Estuary is located on the south coast of Cornwall. It is the county's largest estuary and is important for maritime trade, tourism and conservation in terms of landscape, habitats and species. The estuary extends from its entrance between Pendennis Point and St Anthony Head, 18 km inland to its northernmost tidal limit at Tresillian, with a total shoreline length of 127 km. The estuary is macrotidal with a maximum spring tide of 5.3 m at Falmouth, but is mesotidal at Truro with a spring tide of 3.5 m. The total area of the estuary (2482 ha) comprises subtidal (1736 ha), intertidal mudflat (653 ha) and saltmarsh (93 ha) environments. It can be subdivided into two sections; the inner tidal tributaries and the outer tidal basin. The outer tidal basin is known as Carrick Roads, and forms about 80% of the main water body of the estuary. Carrick Roads is characterised by a deep meandering channel with depths of up to 34 m at the southern end. The channel meanders northwards becoming narrower and shallower to a depth of 12 m near Turnaware Point and continues through the King Harry Reach as the River Fal where it reaches a depth of 5 m. Flanking either side of the main channel are broad relatively shallow platforms that range between 0.3 and 4.6 m deep.

The northern part of the estuary comprises 6 main tributaries and 28 minor creeks and rivers, all of which eventually flow into Carrick Roads. Significant sediment deposition and human modifications have caused many of the creeks to silt up, so that areas which were previously navigable by ships and boats are now impassable. The northernmost branch of the estuary is the Tresillian River, whose creeks include Bar, St. Clements, Tresemple, Kiggon and Merther, the latter three of which were small creeks which were dammed to form fish ponds. The Tresillian River converges with the Truro River at Malpas, which then flows south to join the River Fal. The rivers Kenwyn and Allen flow into Truro River at its tidal limit and Calenick Creek and Lambe Creek flow into the Truro River on its southern side. The River Fal, whose headwaters drain Goss Moor, is tidal to Lamorran Wood, the tidal limit being at Sett Bridge, and receives waters from the Ruan River as well as various small creeks to the south. The River Fal flows westwards before turning south through King Harry Reach to join Carrick Roads at Turnaware Point. The converging waters of Cowlands and Lamouth creeks, together with Channals Creek flow into the River Fal on the eastern side, at either end of King Harry Reach.

Major components of the Fal Estuary

On the western side, south of Turnaware Point, four rivers flow into Carrick Roads including Pill Creek, Restronguet Creek, Mylor Creek and the Penryn River. The Carnon River, which drains the Gwennap mining district, and the River Kennal whose headwaters are located on the Carnmenellis Granite, both flow into Restronguet Creek. Restronguet Creek is tidal to Devoran and Perran Wharf and also receives waters from Tallacks Creek and Penpol Creek on its northern side. The Penryn River, which drains the Carmenellis Granite, converges with the southern end of Carrick Roads and comprises the minor creeks of Gorrangorras and Sailors on its northern side.

The eastern side of Carrick Roads comprises St. Just Creek and the Percuil River. The Percuil River is tidal to Trethem Mill at the northern extremity of Trethem Creek, which then converges with Polingey Creek to join the Percuil River. Pelyn Creek and Porth Creek on the western side, together with smaller creeks on the eastern side, all flow into the mid reaches of the Percuil River.

Viewpoints around the Fal Estuary (click here for a photo tour of the estuary)

There are many good viewpoints around the Fal Estuary; listed below are a number of sites which complement the areas discussed in this CD. The map grid references refer to the Ordnance Survey ‘Explorer 105, Falmouth and Mevagissey, 1:25,000” map sheet.

Warning! Please note that the extensive areas of intertidal mudflat exposed at low tide are very dangerous as the mud is both deep and very soft.

(1) Pendennis Point (SW 826 316) provides good views both seaward and also towards the deep water part of the estuary, Carrick Roads.

(2) Point Quay (SW 810 386) was constructed during the late 18th Century and provides views at low tide of the intertidal mudflats in Restronguet Creek. Looking west from Point the remains of the Restronguet Creek tin works operational between 1871 and 1874 can be seen.

(3) Sett Bridge (SW 887 423), constructed in 1885 on the River Fal, gives a good view of the areas of saltmarsh which have developed after this part of the estuary silted up largely due to the release of waste from china clay mining.

(4) Tregony (SW 921 448) was an early Medieval port but siltation as a result of mining activity meant that ships could no longer reach the port.

(5) Malpas (SW 845 426) is situated at the junction of the Truro and Tresillian rivers. Whilst travelling from Truro to Malpas there are good views east towards Calenick Creek which is heavily contaminated with mine waste tailings.

(6) Trelissick (SW 836 396). The National Trust Gardens at Trelissick provide excellent views overlooking the River Fal along the King Harry reach and also southwards towards Carrick Roads.

(7) Tresillian to St Clements – the footpath follows the edge of the estuary from St Clement (SW 852 438) to Kiggon Pond (SW 859 456). The intertidal sediments in this area comprise mine waste tailings typically peaking in concentration some 30-50 cm below the sediment surface.

(8) Carnon Valley (SW 787 040). A footpath and cycleway follows along the Carnon Valley and provides a useful way to appreciate the impact of mining on this area which drains into Restronguet Creek.

 

Another good way to see the area is by catching one of the cruise boats who sail along the estuary out of both Truro and Falmouth, and also the passenger ferry between Falmouth and St Mawes.