A close watch is being kept on rainfall levels across Christchurch and Banks Peninsula.
The weather forecast though suggests the rain expected over the next day or two should cause little more than nuisance surface flooding on some low-lying streets around the Avon and Heathcote rivers.
Some surface street flooding typically occurs in Christchurch when the city gets more than 40 millimetres of rain within a 24 hour period or if there are sustained heavy down pours in which rain falls at more than a rate of 4 millimetres an hour.
“The current forecast suggests Christchurch and Banks Peninsula can expect between 40 and 60 millimetres of rain over the next couple of days so it is possible we will see some surface street flooding in some pockets of the city,’’ says Christchurch City Council City Services General Manager David Adamson.
“The good news is the tides are unlikely to be as high as they were during last week’s rain event so any flooding we do get should be relatively minor.
“We’re conscious though that forecasts can change quite rapidly so we are monitoring the situation closely and have taken all the usual precautionary steps to ready the city for heavy rain and to ensure the land drainage network is operating as it should be, ’’ Mr Adamson says.
Those steps include getting contractors to check stormwater grates and sumps around the city to ensure they are free of any debris that may cause blockages.
Temporary pumps have also been deployed to the Flockton area, Maces Road and Ebbtide Road.
“In Duvauchelle, Akaroa and Takamatua we are asking people to conserve water. This is because their water supplies come primarily from streams which are difficult to treat when they become dirty with floodwater and we may not be able to fill the reservoirs as fast as water is being used. It generally takes about 48 hours for rivers to clear following rain,’’ says Mr Adamson.