When it rains, it floods: Poor drains upset residents

INEFFECTIVE: Nuisance flooding on Rocking Horse Rd as a result of inefficient storm water drains.

Southshore residents are fed up over inefficient stormwater drains filling up when it rains.

At issue is rainwater being unable to flow out from the stormwater drains on parts of Rocking Horse Rd to the Southshore estuary.

This is due to the pipe running out to the estuary being buried which causes the gutters on parts of Rocking Horse Rd to overflow with rainwater.

It has been an ongoing problem for about six years.

It was noted at a recent Coastal-­Burwood-Community Board meeting there were concerns.

The city council has received five complaints about surface flooding on the road in the past year.

City council land drainage manager Keith Davison said drainage along Rocking Horse Rd is challenging given the low lying nature of the land.

“The city council will continue to maintain the outfalls and pipe networks servicing Rocking Horse Rd. Temporary pumps will continue to be deployed when required,” he said.

Deputy chairman Tim Sintes said he gets “annoyed” because it is often viewed as a flooding issue when the problem is the stormwater cannot get out of the drainage system properly because it is not working properly.

He said the city council bringing a pump down when there is a storm or bad weather is a “Band-Aid fix.”

“This is nuisance flooding that has gone on for too long. The gutters are filling up with rain because the water can’t get out through a system that can’t operate efficiently,” he said.

His views were backed by Rocking Horse Rd resident Warwick Schaffer, who said, the city council hiring a pump every time the street is full of water was a “ridiculous solution.”

He said the gutters overflow with every little bit of rain, which is a “real pain.”

Offshore and Coastal Engineering Ltd managing director Gary Teear said from what he had observed, he thinks the pipe running into the estuary along with other pipes on the road have a rubber duckbill valve at the end of it.

“You have this pipe down at the estuary and you don’t want the water coming up the pipe, so when there is pressure on the estuary side the duckbill is shut.

Mr Teear said when there is water pressure on the inside of the pipe, the valve should open.

But he said because the estuary’s pipe and valve is so large, it takes a lot of pressure to open ­which was why rainfall was not opening it. He said possibly a number of smaller duckbill valves are needed like a manifold, which doesn’t require the same rainfall pressure to open.

HAVE YOUR SAY: Are your street drains flooding when it rains? Email your views to georgia.oconnor@starmedia.kiwi