From Hayle Pump Aug-Sep 2011 issue

An opportunity exists to restore the unique, historic Carnsew Sluices in Hayle

Investigations on site and research have revealed that the sluicing from Carnsew Pool can be restored.

Sluicing was a technically simple and highly effective method of desilting harbours and shipping channels. There are remains of some 15 other sluices in Britain, but none in the condition and form of that at Hayle.

The restoration will provide a unique historic working sluice, which will perform the practical function of clearing out the channel. It is intended that the original machinery and lock gates will be reproduced and the pen stocks will be manually operated, as they were historically. As Carnsew pool is now a nature reserve, it will not be possible, or desirable, to operate sluices on every tide, and it is expected that sluicing will take place during the period of 15th of April to 31st of August, either side of the peak spring tides. The effect will be quite dramatic as water at high velocity; will be expelled from the two banks of pen stocks into the Carnsew channel. At the south end, where the lock gates are situated, there is a curved stone “training wall” which directs the water along the channel. The turbulence created when the two streams of water meet, also aids the scouring process.

During recent archaeological investigations on South Quay the trenches have revealed the entrance to Carnsew dock, the oldest and most significant surviving dock construction on the foundry site built in the earliest years of the 19th century. The trenches have also revealed the timber revetments to slipways, which were constructed much later. The construction of these involved the demolition of the earlier granite and stone quayside and dock walls. The timber work is totally decayed and, unfortunately, cannot be preserved. The slipways were part of later maritime activities of the Harvey Company and were generally of crude and almost temporary nature.

They have no particular significance as historic structures, other than illustrating the development of South quay, over a relatively short period.

The restoration of Hayle sluicing is of great significance nationally and internationally. Many people have recognised the importance of sluicing in Hayle for many reasons – assisting maritime operations in the harbour, and reducing the need for dredging etc. We must also recognise that the historic sluicing will be a feature that will receive national publicity and feature in endless magazines and guidebooks.

By Gary Cartmell of ING.