It is not only his farm that is being affected - so far he has lost about 2ha and more is still being washed away - but the threat to the Maerewhenua irrigation intake and main race.
If the river breaks out of its bed through his farm, it has the potential to wash out the Duntroon water supply, Duntroon wetlands and Duntroon Domain, all in a straight path.
Mr Keeling's property is one of the worst affected by two major floods down the river so far this year, the latest peaking at 1534 cumecs on February 11.
Environment Canterbury (ECan) senior engineering officer Bruce Scarlett yesterday estimated damage so far could cost $300,000 to $400,000 to repair - and it was still happening.
Erosion was worse as the river fell, as saturated banks were easier to wash away.
What was a minor braid of the river before last month against Mr Keeling's property has now switched about 2km upstream to carry a majority of the flow.
The point of impact on his property changed, scouring up to 50m back into his farm along a strip at least 500m long, creating a bend which threatens to break out.
River protection planting has now gone, and is sitting out in the river.
"Most of the damage has occurred over the past four to five days, particularly the last two days," he said.
For a short-term solution, mature willow and poplar trees, some of which are being provided by neighbours Rodney and Karen Lawrence, are being felled, taken to the river and positioned against the bank. They are anchored by wire rope to oil drums filled with concrete buried in the ground.
The aim is to cushion the bank against the strength of the flow and break up waves. Mr Keeling estimated that work will cost him and the Maerewhenua Irrigation Company up to $30,000.
Once the river falls, long-term protection would be investigated. That ranged from protective rock groynes with new planting to trying to redirect the braid back into the river fairway.
River protection work is funded by those who benefit - ratepayers along the lower river, along with Meridian Energy Ltd. ECan contributes 40% from the general rate.
That is administered by the Lower Waitaki River rating liaison committee.
Mr Scarlett said the rates generated an annual budget of about $360,000. Just before the latest floods, $100,000 allocated to spraying noxious plants in the river was used for river erosion protection, and that had so far stood up well in the latest floods.
The last major erosion and damage was after flooding in May, 2009. That cost almost $450,000.
