Greenpark Weir Improvements


Greenpark Weir is a structure dating back to the 1890s, Associated British Ports is responsible for the upkeep of Greenpark Weir. Greenpark Weir ensures a supply of water to Port Talbot Docks and for use in the Tata steelworks. The existing structure is in a poor condition and its failure could have significant consequences. Improvements were made to the design yet there are a number of significant constraints. These ensured the scheme:

  • did not adversely impact the existing fish pass and could be constructed with minimal disruption to the water supply for the docks and steelworks
  • was fully compliant with the 2015 CDM Regulations being safe to construct within a fast responding watercourse
  • met the environmental constraints set out by NRW
  • was capable of meeting exacting hydraulic design criteria allowing a better management of water resources within the River Afan.


We first became involved in an appraisal of options to improve the weir in 2011. This resulted in a recent completion of a detail design to substantially refurbish the weir and allow its continued operation for another 120 years. The construction phase commenced in July 2016 when we supervised the site and acted as the Environmental Clerk of Works and Principal Designer. The final design is a replacement structure comprising a reinforced concrete crump weir with an integral smolt bywas and a reinforced concrete stepped weir.


The new structures have been designed to be structurally independent allowing separate construction to prevent an increase in flood risk during construction.  To allow for better water management to the docks and steelworks automatic penstocks controlled by water level are also included.

Contact us

For more information: Oliver Francis

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