Thames Division is the marine policing branch of the Metropolitan Police, which patrols the tidal section of the River Thames from Purfleet in the east to Teddington Lock in the west.
Thames Division has five police stations, from east to west along the river: Erith, Blackwall, Wapping, Waterloo Pier and Barnes. The division has about 200 men and is headed by a chief inspector (based at Wapping, the divisional headquarters, making it the only division without a superintendent) with two sub-divisional inspectors (at Waterloo Pier and Blackwall). There are three motor launches (Vigilant, Alert and Watch), one at each of the three main stations, as well as 28 motorboats and seven rowing boats, which patrol 24 hours a day, 365 days a year. The launches are 31-35 ft and can make 9 knots. The motorboats are 22-28 ft and can make 6-9 knots. The boats are fitted with wireless in 1935.
Each motorboat is crewed by a sergeant and two constables; the launches have larger crews. The division does not have the CID organisation of other divisions, but does have a detective inspector and a detective sergeant attached for investigation purposes. Automatic pistols are kept at each station for arming the boat crews if necessary, but are very rarely issued. Officers have the powers of customs officers to search for and seize contraband. The division pulls more than 120 dead bodies out of the river every year and a boat is stationed at Waterloo Pier specifically to recover them (since the nearby Waterloo Bridge is the most popular spot in London to commit suicide).