A Thames Water engineer watched a tennis club worker pour liquid into the drain that feeds Wimbledon Park Lake, the Environment Agency has confirmed.<\/p>\n
The club is the All England Lawn Tennis Club, better known as AELTC, which owns land bordering the lake and runs the Wimbledon Championships. It has spent the past year denying any of its staff had anything to do with pollution there, and is separately fighting residents in court over plans to expand its grounds onto the old golf course next door.<\/p>\n
The confirmation is in a letter Putney.news obtained under freedom-of-information rules covering environmental data. It answers a request filed on 9 July, the same day as a separate request to Thames Water, which refused to release anything and which we reported on 7 August<\/a>. <\/p>\n A Thames Water engineer, checking discoloured water and high ammonia levels near an outfall on Church Road during last year\u2019s Championships fortnight, followed the trail onto the tennis club\u2019s own grounds: <\/p>\n \u201cDuring upstream investigations within the All England Lawn Tennis Club (AELTC) site, the engineer reported observing a member of staff pouring liquid into a surface water drain and food waste being present around the drain.\u201d <\/p>\n<\/blockquote>\n His investigation was cut short by security restrictions during the tournament, the letter states.<\/p>\n That account is Thames Water\u2019s, relayed by the regulator, not something an Environment Agency officer saw with their own eyes. For a year this has been residents\u2019 word against the tennis club\u2019s. When Putney.news put a similar account to AELTC in July, after fish died in the lake for the second July running, a spokesperson dismissed it as hearsay<\/a> and promised a fuller answer on what caused the 2025 incident. It has yet to arrive. The regulator\u2019s own file now describes, independently, the same thing residents said happened.<\/p>\n Nothing has followed from it. \u201cIn relation to the July 2025 incident, no enforcement action has been taken against the All England Lawn Tennis Club (AELTC) or its contractors\/agents,\u201d the letter states. Nor has anyone gone back to check: \u201cWe have not carried out any inspection at the relevant drain\/outfall since the incident.\u201d Thames Water and the tennis club set up a working group to look at the site\u2019s drains. It met once, in September 2025, and the letter records that AELTC \u201chad committed to resolving any issues identified.\u201d Almost a year on, nothing has been published on what, if anything, that produced.<\/p>\n AELTC\u2019s defence, unchanged since 2025, is that the drains are Thames Water\u2019s own pipework, not the club\u2019s own drainage<\/a>. That may settle who owns the pipe. It says nothing about what a Thames Water engineer says he watched a member of the club\u2019s own staff do to it.<\/p>\n The club has never had permission to put anything down that drain at all. \u201cThe AELTC site has no discharge Permits or Consents into the lake,\u201d the letter states. Thames Water has two old overflow pipes into the same stream, at Church Road and Home Park Road, that have also never been brought under permit.<\/p>\n Putney.news put the eyewitness account to AELTC on 10 August and are awaiting a response.<\/p>\n This year\u2019s problems<\/p>\n This year\u2019s fish deaths are a separate story. The regulator\u2019s account of the July 2026 kill has not changed: heat, and a bloom of a blue-green algae called Aphanizomenon, not pollution. Its officers found the water\u2019s dissolved oxygen had crashed to about 2.2 milligrams per litre, less than a third of what a healthy lake needs to keep fish alive, and ammonia at levels high enough to irritate fish gills, though not on their own enough to kill.<\/p>\n Mapping the coordinates in the letter, this year\u2019s water test was taken within about 35 to 55 metres of where the 2025 incident happened, and nobody has checked that stretch of drain this year either. That is not evidence the club is involved: dying fish and algae produce ammonia themselves as they decompose, and the regulator\u2019s heat-and-algae finding stands on its own evidence.<\/p>\n AELTC\u2019s wider expansion of the site returns to the Court of Appeal<\/a> after a judge ruled the residents\u2019 campaign group has a real case to argue that the land is protected for public use. A hearing is not expected before 2027.<\/p>\n\n