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  • The Site Location
  • Excavation Underway
  • Cesspool in place
  • Completed Installation

Project: Oyster Farm, Port Navas, Cornwall

Faced with Environmental, Archeological and Physical constraints, ALRO stepped-up to the challange of replacing the cesspools serving the shore facilities of an Oyster Farm.

The Oyster Farm owned and operated by the Duchy of Cornwall requires that excellent water quality be maintained at all times. In addition, the historic harbour walls within the area are guarded by archeological protection legislation. To bring the Sewage and Waste Water disposal system up to current standards, a number of obstacles needed to be tackled.

Of the two GRP (Glass Reinforced Plastic) Cesspools to be installed, the smaller was installed within the footprint of one of the previous (now defunct) concrete cesspools.

However, installation of the second larger cesspool proved to be a considerably more complex affair.  As can been seen in picture 1 below, the available space was limited and constrained by the stone walls.

Picture 1 - The intended location for the larger Cesspool.

To maintain the integrity of the harbour-walls as well is that of the overall excavation, shoring and light-piling was used.

Picture 2 - Shoring in place to maintain integrity of the ancient walls.

Our personel were provided with accommodation close-by, negating the need for a long drive to and from site.

Picture 3 - Sunset over the Helford River, project nearing completion.