Polson St resident John Maulder is furious most of his section is a sheet of shallow water at times every winter.

He wants Whanganui District Council to alter Titoki Wetland, which he believes is where the problem started. The response he's had so far is "all lies and excuses", he said.

The water table has risen across parts of Castlecliff, so that parts of sections and paddocks have been covered in shallow water at times during the last few winters.

In Manuka St, Linda Osman's house sits on a slight rise. Water has been 150mm deep across her driveway for three months, and flows from there across the front of her section.


She said it's the fifth year this has happened, and she watched 31 ducklings in her drive the other day.

In Polson St one of Maulder's neighbours can't paint his swimming pool, because the bottom is always full of water.

Maulder believes the problem started from council "backfilling" at Titoki Wetland around 1988, and has slowly made its way across the suburb.

The fill raised water levels there 1.5m, he said. He believes lowering it by that much would solve the problem. He has kept records, complained, presented a 70-signature petition and shown the water situation to people of influence.

It's all to do with changes to groundwater, council senior stormwater engineer Kritzo Venter said. The water table has risen.

"It's almost above ground level in places."

But it would have to be above house floor level to be called flooding.

The council does not offer a formal service to manage groundwater levels, and Venter said water tables can be changed by earthquakes, deforestation and the shifting of underground streams.


Titoki Wetland is actually lower than Polson and Manuka Sts and filling there could not possibly be the cause of a higher water table, he said.

Maulder has the option to do his own subsoil drainage and connect to the council stormwater system, at his own expense. For Osman, the problem is more difficult.

There is no stormwater pipe in Manuka St, and will not be for years, Venter said.

"There's nowhere for [the water] to go."

Titoki Wetland is a high-priority swamp remnant, with cultural and historic significance. Draining it would require resource consent, which would be unlikely to be granted. It would not be permitted under Horizons Regional Council's One Plan.

The council has finished modelling stormwater flows in Whanganui, Venter said, and resulting decisions have been prioritised in its Long Term Plan.

Top priority areas for new pipes are the Mill Rd Industrial Zone, and for an improved level of service are the central city, Springvale and western Aramoho.