Originally a small pool named Roach Pool in Rotton Park, it was extensively enlarged by
Thomas Telford between 1824 and 1829 to supply water to the
Birmingham and Wolverhampton Levels of the
Birmingham Canal Navigations (BCN) canal system: via a culvert and the
Engine Arm to the Wolverhampton Level, and via
Icknield Port Loop at the foot of the dam to the lower Birmingham Level. It was excavated to a depth of 40 feet (12 metres) and covers an area of , holding of water, and was the largest expanse of water in Birmingham at the time. It is supplied by small streams and a feeder from
Titford Reservoir (Titford Pools) in Oldbury. It was formed by damming a small stream. The dam is a long earth embankment with a height of near the centre. The reservoir and gatehouse were designed by Thomas Telford and the latter is a two-storey
listed building in corporate BCN octagonal style, with a later extension dating from 1880. In 1873, the reservoir was crossed by
Charles Blondin, on a
tightrope. His feat is marked by a 1992 statue on the nearby
Ladywood Middleway ring road. In 1876, a
skating rink was opened near the gatehouse. By the 1920s the building was more popular as a
dance hall, and was renamed the 'Pavilion Ballroom', and then in 1933 the 'Tower Ballroom'. The
Tower Ballroom remained open in some form until 2017, when it was forced to close due to rent costs. It reopened briefly in 2019 to host
Birmingham Opera Company's acclaimed production of
Lady Macbeth of Mtsenk, but was subsequently demolished in 2022 with the site remaining vacant as of 2024. ==Ecology==