The first designated bathing water area on the River Thames in London will welcome swimmers for the official start of the bathing season on Friday as one of 13 new monitored swimming areas across England.

The Thames at Ham, in south-west London, has been designated as a new river bathing water area after campaigners gathered evidence to show thousands of people use the river for swimming throughout the year.

Marlene Lawrence, the founder of the Teddington Bluetits, which has more than 2,000 members, put in the bathing water application alongside her colleagues.

“This is amazing for the river and for the many people who enjoy it,” she said.

“We want bathing water status to be a driver of keeping the River Thames clean and it will be fantastic to have this part of the river designated.”

Other locations which have been designated as bathing water areas include a tidal inlet just off the River Yealm in the south Devon; part of the River Fowey in Lostwithiel, Cornwall; the River Dee at Sandy Lane, Chester; a sea swimming area at Little Shore, Amble, in Northumberland; Pangbourne Meadow in Berkshire, which inspired the novel The Wind in the Willows; and the River Swale in Richmond, Yorkshire.

Water minister Emma Hardy said: “The introduction of these new bathing sites means better monitoring of our waterways, a boost for local tourism and greater confidence for local swimmers.

“Following years of indifference towards bathing waters, this government has expanded the number of sites as part of our overhaul of the water sector.

“We’re committed to generational reform of our water industry and won’t stop until the job is done.”

Campaigners began fighting for bathing water status for rivers six years ago under the EU-derived bathing water directive, in an attempt to drive a cleanup.

Bathing water designations were until then limited to coastal waters and lakes. But rivers are suffering from a toxic cocktail of sewage discharge from water companies, forever chemicals and road and agricultural runoff and campaigners hope the more rigorous testing which is required for bathing waters will force water companies to reduce sewage pollution.

Tests in bathing waters by the regulator, the Environment Agency, have to monitor the water for faecal indicator organisms.

Every week throughout the summer, officers from the Environment Agency will visit sites to take samples and monitor the water quality before publishing the information online for swimmers.

The regulator said it constantly evaluates whether action is needed to cut pollution levels and works with local communities, farmers and water companies to improve water quality at these locations.

At Ilkley in West Yorkshire, where the Wharfe became the first river to be given bathing water status five years ago, Yorkshire Water is implementing infrastructure improvements costing more than £85m ito boost water quality.

The new bathing water sites that are designated from this month – until the swimming season concludes at the end of September – are:

• Canvey Island foreshore, Essex

• East Beach at West Bay, Bridport, Dorset

• Falcon Meadow, Bungay, Suffolk

• Granville Parade Beach, Sandgate, Kent

• Little Shore, Amble, Northumberland

• New Brighton Beach (east), Merseyside

• Newton and Noss Creeks, Devon

• Pangbourne Meadow, Berkshire

• Queen Elizabeth Gardens, Salisbury, Wiltshire

• River Dee at Sandy Lane, Chester, Cheshire

• River Fowey in Lostwithiel, Cornwall

• River Swale in Richmond, Yorkshire

• River Thames at Ham and Kingston, Greater London