Funding finally confirmed for major M27 Hamble bridge works after nearly two decades of concerns

At a recent meeting of the River Hamble Harbour Authority (RHHA), it was revealed that National Highways (NH) has confirmed the bridge is included in the Government’s Draft Road Investment Strategy 3 (RIS3) programme, published in August.

National Highways confirmed on the same day that funding has been secured during the RIS3 period to carry out major works to the M27 bridge over the estuary.

The proposals include structural strengthening and refurbishment works, alongside upgraded drainage provision.

For more than 20 years, councillors and campaigners have warned that a serious collision on the bridge, or routine rainwater laden with hydrocarbons and heavy metals from the carriageway, could lead to an environmental disaster for the River Hamble and its estuary.

Planned works also cover improvements to the bridge deck drainage system, repainting of steelwork, re-waterproofing of the bridge deck and replacement of bridge joints.

NH said recent structural assessments have confirmed the bridge remains suitable for normal road traffic, but described the required works as “exceptionally challenging”.

Detailed design work is currently expected to begin in 2026/27, with construction provisionally scheduled to start in 2027/28.

However, National Highways has said a key technical challenge remains whether it is practically and economically viable to strengthen the bridge sufficiently to remove all load restrictions.

It added that the current drainage proposal would involve modifying existing downpipes and collecting surface water from the bridge via carrier drains running the length of the structure.

Once at ground level, the water would discharge independently from the highway drainage system into the river, with appropriate pollution control measures in place.

The exact details of the drainage solution are still being developed as part of an options report prepared by NHs’ consultants, and no further information is available.

In September, Transport Action Network (TAN), which has been pressing for action on toxic runoff nationally and locally, says the bridge’s drainage problem is “far from unique on England’s major roads”.

More recently, a TAN representative met with local councillors to discuss actions and campaigns aimed at addressing the bridge’s drainage and outfalls.

The group shared details of its wider work investigating road runoff and advocating for stronger mitigation measures.

Councillor Michael Ford, chairman of the River Hamble Harbour Board, involved in the conversations said: “Run offs from the M27 Bridge into the River Hamble has been an issue for some time and the River Hamble Harbour Board (RHHB) continue to raise the issue with National Highways.

“The bridge is scheduled for strengthening in any event and we would wish to see both issues addressed with some priority.

“The difficulty for the Harbour Authority is that this responsibility falls outside of their remit as they are neither the polluter nor the regulator.

“The Authority can only therefore keep highlighting the problem to try and ensure that addressing these outfalls remains a priority.”