Drainage services
in Portsmouth

Portsmouth's drainage problem is fall, or the lack of it. Most of the city stands on Portsea Island, between Portsmouth Harbour and Langstone Harbour, and most of the island is less than three metres above sea level. On ground that flat, sewers and house drains have very little slope, so fat, wipes and silt settle in the pipe instead of washing through. The sea and the water table are never far below, and a small dip in an old pipe holds water for good.

The pipes are old. The city's sewers were built between 1865 and 1870, after a cholera epidemic, and a by-law made any house within 100 feet of a sewer connect to it. In 1887 the Eastney pumping station was built to hold sewage and pump it out on the ebb tide. Behind that system the island filled with terraces: Fratton and the districts around it went up mostly in the 1870s and 1880s. Clay pipe of that age, packed under houses this close, is the typical Portsmouth drain, and its joints have opened.

Off the island the drains are younger. After the Blitz, Portsmouth rehoused families on the mainland: Leigh Park was started in 1947, Havant's housing more than doubled in the twenty years after the war, and Waterlooville, Fareham and Horndean grew fast in the 1950s and 1960s. So on the mainland you mostly find post-war estate drainage, now 60 to 75 years old, often in shared runs behind rows of houses. Roots, shifted joints and silted shared lengths are the usual faults there.

Southern Water runs the sewers. Its Budds Farm system serves most of Havant borough, and Emsworth drains to Thornham. Drinking water comes from Portsmouth Water, which draws on boreholes in the South Downs and the springs at Havant and Bedhampton. Since 1 October 2011 Southern Water has owned sewers serving more than one property and lateral drains outside your boundary. That covers many of the shared runs behind Portsmouth's terraces, so before you pay for a repair, find out whose pipe is broken.