An historic Bushy Park water feature is now open to the public after a lengthy £780,000 restoration project.

The baroque water garden, built in the 18th century by Charles Montague, the first Earl of Halifax, at the Hampton Hill end of the park has reopened after a refurbishment scheme stretching back more than a decade.

The gardens - a collection of pools, cascades, basins and a canal - disappeared beneath undergrowth and silt after the Ministry of Defence (MoD), which used it for research into submarine technology in the 1950s, relinquished its lease 15 years ago.

In 1997 the Friends of Bushy and Home Parks formed the Bushy Parks Water Gardens Trust to restore the gardens and the Royal Parks Association, which operates the park, took the lead on the project and work began in January last year.

Greg McErlean, director of major projects at the Royal Parks, said: “Starting as a degraded and unsafe heritage asset, little known and out of the public eyes, the gardens have been transformed through detailed research, design, quality workmanship, and support from the local community.

“By bringing to life this unique landscape we hope the gardens will prove to be a popular addition to visitors’ enjoyment of the park for many more years to come.”

The restoration of the gardens, which were used as a hospital for Canadian troops during World War I and as a US barracks during World War II, was based on an 18th century painting. A brew house on the opposite side of the Longford River from the main site was also restored.

The Heritage Lottery Fund stumped up £4.5m of a £7.2m project to restore formal gardens and buildings in Bushy Park and donations also came from The Crown Estate, the Royal Parks Foundation and the Friends of Bushy and Home Parks.

Pieter Morpurgo, chairman of the friends group, said: “We have been particularly proud of our initial input to this project by carrying out the early historical and archaeological research and setting up the Water Gardens Trust.

“The efforts of the friends, and especially our former chairman, Kathy White, enabled the production of a Restoration Master Plan with a grant from the Heritage Lottery Fund. This has formed the basis of the restoration completed by the Royal Parks.

“The friends are delighted that their efforts have initiated the remarkable restoration of the gardens opening today. It is a wonderful garden which the public will enjoy for generations.”