Flood-waters on roads and parks may be contaminated, the council has warned.
Residents are being advised to avoid the water where possible or to wash their hands and remove and wash any clothing that gets wet.
Drivers have been asked to slow down when driving through flooded areas as vehicle wake can send waves into homes and businesses.
Extra care needs to be taken when driving on Cressy Terrace/Park Terrace, Lyttelton due to slips.
Geotechnical consultants are monitoring known risk areas.
"The council is asking people in hillside areas to be vigilant, and keep an eye out for any telltale signs of land instability, including new cracking to land, buildings, driveways or paths; existing cracks that get longer, wider or deeper; leaning or bulging of retaining walls; or rockfalls.
If anyone notices changes, or has concerns, they are being urged to call the council's call centre on 941 8999, or 0800 800 169.
Road closure information is continually changing. For up-to-date traffic information throughout Christchurch city and Banks Peninsula, please visit the Transport for Christchurch website at www.transportforchristchurch.govt.nz
Otago flooded
North Otago bore the brunt of the latest low to slide across the east coast, with 60mm of rain falling in 24 hours.
State Highway One at Hilderthorpe, north of Oamaru, is closed this morning and detours are in place.
Further north, widespread surface flooding has closed some streets in Christchurch.
Video: RainWatch: (APR28) Dry weather returns
MetService said 45mm of rain has fallen in the last 24 hours and another 20mm is expected this morning.
Yesterday, the Waitaki District Council activated its Civil Defence emergency operations centre at 2.30pm, as the rain continued to bring high river levels and caused surface flooding in North Otago.
Just south of Oamaru, 53mm fell at the Dasher in the 24 hours to 5pm yesterday.
Civil Defence local controller Murray Linwood said Pukeuri, Hilderthorpe and Alma had the worst surface flooding yesterday.
The Kakanui River at Clifton Falls peaked at 200 cumecs and was falling at 8.20pm.
All roads in the Corriedale ward network were closed, along with another six rural roads - Bobbing Creek Rd, Elderslie Rd, Herbert Rd, Paterson Rd, Turfus Camp Rd and Weston-Ngapara Rd.
Caution was urged on State Highway 83 from Pukeuri to Duntroon, with some areas closed to light vehicles.
Mr Linwood said more costal rain meant affected areas differed from Easter's flooding event.
The Oamaru Volunteer Fire Brigade was called to sandbag and pump water from houses on Eden St, Beach Rd, Coquet St, Arun St, Lismore St and Alt St yesterday.
''A lot of people have come home from work to find water in their basements,'' Waitaki District Council rural fire officer Steve Couper said.
''[It's] nothing serious at this stage. We're just working our way around them and doing what we can.''
Volunteer firefighters spent about 15 minutes sandbagging this Beach Rd property near Oamaru yesterday. Photo / Rebecca Ryan
Waitaki District Council roading manager Michael Voss said continued wet weather had delayed routine road maintenance and damage repairs around the district.
Mr Voss urged farmers to take extra care when moving vehicles from paddocks on to the road to prevent a muddy and slippery surface for other road users.
''Any cost incurred by the Waitaki District Council to clean the road surface of mud from farm vehicles on the road will be charged back to the property owner,'' he said.
Last night the MetService continued to warn of heavy rain for the region until midnight but lifted the warning for Dunedin.
''It has all but gone from Dunedin. There might be scattered rain tomorrow morning but it should clear up in the afternoon,'' a forecaster said.
Heavy rain also fell in the hills around Dunedin, with 39mm recorded at Sullivan's Dam in the 24 hours to 5pm yesterday, 15mm in the city and 25mm at Pine Hill.
However, the rain caused only minor surface flooding in some places around the city.
The Water of Leith in Dunedin rose briefly as a result before dropping.
Similar amounts fell in the headwater of the Taieri River, with 25mm at Ranfurly and 20mm at Middlemarch causing the river to rise to its first flood alert level at 100 cumecs at Tiroiti.
It was at 129.8 at 8.15pm.
At Mosgiel, 24mm fell in the Silver Stream, raising it to a peak of 24 cumecs yesterday afternoon.
A similar amount fell at Dunedin airport.
In Central Otago, a large tree brought down by strong winds about 7pm was blocking Mt Aspiring Rd.
Road closures
Road closures covered by temporary traffic management:
Carrick Street
Thornton Street
Archer Street
Harrison Street
Whareoa Terrace (slip)
Fitzgerald Avenue Northbound left lane closed
Owles Terrace Pages Road Collingwood Street
Aylesford Street, Hills-Westminster
Speight Street
Flockton Street, Warrington Street-Westminister Street
Fifield Terrace St Martins Road to Beckford Road
Richardson Terrace McKenzie-Opawa
Clarendon Terrace - Sheldon-Opawa
Aynsley Terrace - Garlands-Centaurus
Smith Street
Riverlaw Terrace Armstrong Avenue - Tennyson Street
Eastern Terrace - Birdwood Avenue to Waltham Road
Waimea Terrace Colombo Street Birdwood Avenue
Earnlea Terrace
Hunter terrace Colombo to Malcolm Avenue
Deans Ave Riccarton Road Moorehouse Avenue
Little River Road
Martindales Road
Slater Street
Warrington Street, Hills-Barbadoes
Squire Street
Harrison Street
Barbados Street- adjacent to Edward Avenue
Edward Avenue Barbados to Geraldine street
Summit Road, Sign of the Kiwi to Gebbies Pass
Brittan Terrace Above the port is open to light vehicles only
Western Valley Road Little River to Port Levy
State Highway 75/Hilltop Road Cooptown to Barrys Bay
Source: AA RoadWatch website
