It is administered by the
London Borough of Richmond upon Thames and
Port of London Authority. Its west part was last accurately measured as ; its east being longer and the same width. The ait has a gap in the middle known as Hog Hole which is apparent at lower high tides, dividing the ait into "upper" and "lower" sections which are awash with water at
mean high water springs. The ait was also known as Makenshaw, Mattenshaw or Twigg Ait. For reasons likely connected with ownership the
ancient parish of
Kew in
Surrey included Brentford Ait in its history; the
London Borough of Hounslow governs neighbouring
Lot's Ait separated only by thick, shifting mud at low tide from Brentford whereas channels beside the dual ait are dredged. In the 18th century the ait was inhabited; a main building was a latter-day notorious pub, the Swan or Three Swans; its trade was ended in 1796. On the Brentford bank, the Swan Steps lead down to the river at the east end of the long and narrow park, Waterman's Park. From these the crossing to the pub ran. The ait has borne large trees since the 1920s to screen Brentford's
gasworks (since removed) from the view of
Kew Gardens. The ait is covered by
willows and
alder and is a
bird sanctuary with a significant
heronry. ==See also==