Kingston council has agreed to investigate the possibility of turning a historic site previously used to supply clean water to the capital into a public nature reserve.

It comes as part of a set of recommendations concerning the future of the Seething Wells filter beds, in Surbiton, which have been approved by Kingston Council.

The filter beds, built in the 19th century, received water from the River Thames and stored it while it was filtered through sand, gravel and shells ready for pumping into reservoirs. Thames Water decommissioned the site in 1992 and it is now privately owned by Cascina Limited.

Seething Wells Action Group (SWAG), made up of local residents, has been campaigning for the site to be turned into a nature reserve for years. A councillor working group was formed to investigate options for the site's future in 2022 and held a series of public meetings before putting together formal recommendations.

The council's place committee unanimously approved the recommendations, outlined in a report, on September 21. The report said there has been "increasing concern regarding ongoing maintenance activity" on the site and the potential impact on wildlife.

The approved recommendations include the council exploring and calculating the cost of providing a nature reserve on the site for public access, heritage and nature conservation, including the possibility of designating the site as a local nature reserve with the owners. The council is not the landowner so it can't designate the site as a local nature reserve itself.

The group also recommended the council use independent advice to value the land to understand available options including buying or leasing the site, to negotiate with the owners regarding potential council or trust management of the site and to potentially apply to Historic England for the site to be listed.

Other recommendations are for the council to pursue opportunites through environmental schemes and third-party organisations to restore and improve habitats on the site, and to seek "proactive dialogue" with the owners to enhance management and maintenance of the site.

The council is set to provide updates three times a year to the Surbiton neighbourhood committee, and annually to the place committee, on the actions taken on the recommendations it has supported.

Members of local campaign group Seething Wells Action Group (SWAG) spoke in support of the recommendations at the meeting. Member Sarah Onions, who sat as a community representative on the working group, said Kingston is an "affluent borough" which could "do something really fantastic" with the site.

She said: "I think it's really important that there is a space there for nature, some sort of nature reserve on that space. We've worked really hard, SWAG has worked very hard, to build the evidence and the evidence is all there about the degradation of species on the site, pollution, air traffic pollution, the importance of that site relating to being by the Thames and being next to Surbiton and the evidence has come not just from us it's also come from the Friends of Seething Wells and from other groups."

Phil Renton, co-chair of SWAG, said the site has a "fantastic historical significance" as part of London's historic water supply. He said: "We've got a historical, an archeological, industrial heritage unique to Britain and I would suggest those filter beds are unique to the world in terms of what remains of them after the insidious destruction that's gone on over the last two or three years by the owners."

Comments from Lib Dem councillor Liz Green read out at the meeting said: "My sincere hope is that the council and community will get some control of the site in the future and enable it to become a thriving and recognised local nature reserve with recognition of its historic past and I believe that approving all of the recommendations will help us to achieve that aim."

But Lib Dem councillor Roger Hayes warned there is still "a great deal to be done and therefore the diligence of community and council is undoubtedly needed if the ultimate aims are to be achieved".

He said: "Unfortunately, although the owners are better than they were, I'm afraid they were really not very good at all not so long ago which is why it has fallen into the disrepair that we see it in today so hopefully they will continue to improve in their attitude and their behaviour and that we can collaboratively find a solution both for the benefit of the community and the benefit of the heritage and the biodiversity which that site is capable of supporting." 

The committee approved the recommendations at the meeting.

A Cascina Limited spokesperson said: "The landowner would like to reiterate that the site has never been a nature reserve. Any vegetation that colonised the site was self-seeded (wind-borne) plants and trees that had to be removed as they were undermining the structure. The only way to deliver these community aspirations is a compromise by both parties brought about by enabling development."