
Environment minister Elliott Morley has pledged action to protect the river Thames from untreated sewage.
Thousands of fish were killed after 600,000 tonnes of sewage was forced into the river during Tuesday's storms.
Mr Morley said "doing nothing was not an option" to prevent a similar catastrophe happening again.
But a proposed 22 mile long, £2bn sewage tunnel under the river to protect London's wildlife might prove too costly and slow to build, he added.
The scheme, known as Tideway, would add about £12 a year to the average water bill.
The BBC website has further information.