The drowned river valley that is the Milford Haven Waterway winds itself west to the sea and provides both a natural harbour of significant economic importance and a marine and estuarine environment of international nature conservation importance.

The Milford Haven Waterway did not go unnoticed by distinguished figures such as Admiral Nelson, visiting Pembrokeshire in 1802 whilst in between wars. He described the Milford Haven Waterway as “the finest port in Christendom”. 

As one of the deepest natural harbours in the world, large shipping is a regular sight on the Waterway. Ferry traffic, Liquid Natural Gas and oil tankers as well as refuelling ships and tug boats are frequently seen making way along the Waterway.

The Milford Haven Waterway lives up to its name by providing shelter for recreational water craft along the otherwise exposed stretches of the West Wales coast. 

The Milford Haven Waterway is fully saline and wave exposed towards the outer reaches and brackish towards the unspoilt upper sheltered reaches. The inlet has a mean Spring tidal range of 6m and fast tidal streams.

The different types of seabed and foreshores along its length include soft mud, gravelly mud, boulders and bedrock. All these different environmental factors provide habitats for an abundance of wildlife.

Areas of mud and muddy gravel support rich and productive shellfish and worm communities, providing an essential food source for large numbers of over-wintering waders and wildfowl.

Stable boulders and bedrock in the upper reaches of the Daugleddau support spectacular underwater assemblages of colourful anemones, sprawling current-swept sponges and seasquirts, with species diversity increasing towards the entrance of the Waterway.

The majority of the foreshore of the Milford Haven Waterway is designated as a Site of Special Scientific Interest for wildlife and geological interests.

The entire Waterway is included in the Pembrokeshire Marine Special Area of Conservation.

However, despite the ongoing pollution incidents, it wasn’t until 1991 that a one-day conference to address pollution affecting the Milford Haven Waterway was convened by the local authority. 

A key presentation by the Shetland Oil Terminal Environmental Advisory Group (SOTEAG) undoubtedly sowed the seed for the establishment of the MHWESG. 

The Milford Haven Waterway Environmental Monitoring Steering Group was established just a few months later following discussions prompted by the conference.

Membership comprised the major industries around the Haven, the Port Authority, local government and statutory environmental agencies.

The Group’s stated vision was:

‘To provide high quality environmental information to enable members of the Group, and other authorities and industry working in and adjacent to the Waterway, to contribute to the maintenance and enhancement of the rich and diverse marine environment of the Waterway.’

This remains the Group’s vision today.

The Group continues to achieve this vision by considering existing and future monitoring needs, collating and interpreting data and information for its members, and funding future monitoring.

This is funded by members contributing to a shared financial resource.

Members agree to focus the Group’s attention on scientific and technical issues only. Political and management issues are explicitly excluded.

This agreement is instrumental in contributing to the continuous cordial working relationship between members.

For more details of the origin and development of the work programme of the MHWESG, a comprehensive account is available here.