There’s a growing feeling that the huge problem of tree debris and other rubbish clogging the district’s rivers whenever it floods is a problem that needs some positive action.

After the torrential downpour last weekend, huge masses of branches, trunks and whole trees washed down streams and rivers across the district.

A monster pile-up against the piers of the Uawa River bridge at the entrance to Tolaga Bay raised fears for the bridge’s structure.

And debris battering against the Whatatutu bridge buckled the centre and tore off part of the railing.

Debris scoured across low-lying land, taking out pasture and fences — and beaches all along the coast are now covered in the tangled aftermath of the rainstorm.

District Council rivers and drainage assets manager Jurgen Komp says river debris costs a lot of money in terms of the damage and clean-up that’s required after such an event — and the weekend’s floods certainly highlight the fact that a more active approach is needed.

“But of course it all costs money — and buckets of money is not something the council and its ratepayers have in plentiful supply.

“What we really need is for the whole community to take ownership of the problem, and for each sector to take its own action.

Mr Komp says that includes residents who think nothing of emptying their garden waste and clippings down the riverbank, to the forestry companies being careful with prunings and logging waste, to landowners who have old willows and poplars along their waterways.

“By and large, we have no problem with the forestry companies — the main source of all this tree debris is the old willows and poplars that were planted for erosion control years ago, and are now dying or falling over,” he says.

“When they get big and old, when they fall they pull out a big amount of bank with them, get washed downstream and jam against something like a bridge.

“Then they’re so big they trap smaller debris in their branches and act as a dam, with more and more piling up behind, blocking the water flow.”

Mr Komp says the pressure of flood water backed up behind such tangles can be enormous — and very dangerous because they can suddenly release without warning.

Gisborne Wairoa Federated Farmers president Hamish Cave agrees it’s a major problem and one that needs all parties to tackle.

Mr Cave says it’s not helpful for the various sectors to point fingers at each other — farming and forestry are both valuable to the district, and they and other landowners and the council all need to work together to find answers.

“It may well be that council will come up with new policies in future reviews of the district plan requiring landowners and land users to be more pro-active in stopping tree debris getting into our waterways,” Mr Cave says.

Both Mr Cave and Mr Komp say people who own and use land bordering the waterways can start taking action in their own interests, right now.

“One idea that is already being used in some areas, is to create riparian exclusion strips along river banks where there’s forestry,” Mr Cave says.

“A similar thing could work here, with landowners and users pulling back from the very edge of waterways, clearing trees and other rubbish from the banks, and perhaps even encouraging native revegetation along the banks.”

He believes council should certainly take a look at the problem in view of the damage and cost to the district.

Mr Komp says if those along waterways took a look at their old willows and poplars, and removed them before they became a problem, that would be a start.

“They need to be cut into lengths shorter than four metres — so they won’t jam across bridge piers — and the cut rubbish needs to be pulled back far enough so it can’t easily wash into the river in a flood.”

Mr Komp also says landowners could consider buffer strips along the rivers and streams, and says all sorts of riverbank grasses are available for soil protection, even if owners don’t want to plant in natives.

He says council’s budget for such work is limited — he only has some $300,000 to maintain some 63 kilometres of stopbanks — and has virtually nothing to spare for wider vegetation clearance and replanting.

However he believes council would look favourably at some form of help and participation if landowners or community groups put together an action plan.

Mr Cave says much the same thing — and says after this latest flood event, it might be time for everyone to review what they’re doing and see what they can do to lessen the debris problem.

“Mind you, when you get over 450mm of rain in such a short time, virtually nothing you do is going to stop there being a problem! However, we could make it less of a problem.

“It’s always going to be difficult in steep hill country — similar problems happened down in Wairoa and northern Hawke’s Bay at the weekend — but with the millions of willows and poplars planted during catchment board days, we certainly need to take another look at what we can do.”

Mr Komp says the community has been very successful in taking combined action on other problems, such as cleaning rubbish from the beachfront, and he says it might be time for something like an Adopt-a-Stream scheme.

“We probably don’t want more rules and regulations — but council can play its part if landowners, community groups and others get together and propose actions on their own initiative.

Both he and Mr Cave says there’s certainly a need for everyone to be much more aware of the tree debris problem.