The National Rivers Authority together with wildlife conservation groups in Berkshire, Oxfordshire and Wiltshire, are working with the local water authority to re-establish the otters.
"Otters vanished from the area in the late-1950s and 1960s because of excessive river pollution," said a spokesman for Thames Water. "We don't want to artificially re-introduce otters into the area, so we are building homes for them to find."
Each new otter holt consists of an underground chamber measuring two metres square with access, via pipes, to the river and nearby land. The chambers are divided into "rooms" with concrete slabs.
The locations of the holts are being kept secret to protect the otters' privacy, but all are along the river Kennet in Wiltshire. The initiative follows a similar scheme along the upper Thames last year.
The sites were selected by Mark Satinet, the Kennet Otter Habitat Project Officer with the Wiltshire Wildlife Trust. "Otters were once found throughout England," he said, "but pollution and habitat loss have caused their numbers to decline rapidly. These new apartments are ideal ... as [otters] are secretive creatures and like dark, quiet places near water." Otters were recently seen in the area for the first time in 20 years. John Lawrence, Thames Water's waste manager, said: "We want to do all we can to make life easier for the otters now they are returning to the region's rivers." Thames Water has invested pounds 550m in improving sewage works in the region and plans to spend another pounds 300m by the turn of the century. "Our investment at sewage treatment works has paved the way for their return ...We hope that new riverside pads will make them feel even more welcome."Reuse content