Project Overview

Over a 3 year period Dawnus carried out major civil engineering works on this fast track project, which is one of the largest hydrocarbon projects of its kind in Europe.

Our works were divided into three packages, enabling works (£5.7m), civils and buildings groundworks (£9.5m) and civils completion works (£19.8m). Works included: 

  • All foul and surface water drainage (4,800m)
  • 872m of rising main and 425m of French drains
  • 4,200m concrete channeling
  • 8,300m of 800mm diameter fire main
  • 13,867m of electrical trenches
  • Installation of valves and hydrants for the Firewater system
  • 54,000m² concrete paving
  • All permanent site access roads (over 3km)
  • Car parking facilities for 900 vehicles
  • All site clearance and bulk earthworks including rock excavation (over 100,000m³)
  • Fabrication storage and lay down areas
  • Site security fencing
  • Power supplies
  • Access stairways to Gas Tanks
  • All concrete substructures for all sub-stations and central control switchroom building
  • Lagoons
  • Landscaping works 

All works were carried out on a brownfield site, formerly an Esso Refinery. Following consultation with the Environment Agency it was agreed that all ground and surface water would be required to pass through a system of lagoons prior to entering the estuary. Regular liaison meetings were held with the local authorities as well as the Countryside Commission for Wales, DEFRA, EA, HSE and Milford Haven Port Authority to keep them informed of our activities. 

Turnover on this project was regularly in excess of £1m per month and Dawnus was able to react to and achieve the necessary outputs with its own directly employed workforce and plant; at the project’s peak we had 120 directly employed operatives and 20 management staff working on site.

Project Gallery


CB&I John Brown


Milford Haven

Project Value


Contract Period

3 years