Many potato growers were among the businesses affected by the restrictions placed on 650 irrigation abstraction licences last summer. And unless significant rain falls this winter, most will face similar restrictions – or worse – next summer.
But there are measures growers can take to minimise the impact on their businesses – and become more efficient, judging by the experiences of Norfolk potato grower and BAWAG chairman Tim Papworth.
About 80% of his farm’s 1500ha is irrigable, and thanks to the practices he has instigated, water use on the main farm at Tuttington Hall has halved in the past 10 years. “In 1996 we used 151,359cu m,” he says. “With better water use efficiency, that came down to 62,204cu m this year.”
Irrigation requirements are considered very early in the planning process, including which type of potato crop is suited to which fields, he says.
“We have seven abstraction points across the farm. In fields where there are surface abstraction points, we plant salad and early varieties. That way, any water abstraction takes place before low flows become an issue.”
Later and other varieties are planted where there are deep wells so that they are less susceptible to low flows, says Mr Papworth.
The farm is on a very fine, sandy loam soil, which is prone to slumping, so he leaves stubbles in place and subsoils in September. “This helps rainwater to percolate the soil and recharge the aquifers. In effect, we are harvesting rainfall.”
Ploughing doesn’t happen until the spring. “Planting then takes place across slopes so that any water is caught by the rows of potatoes and we don’t get run-off. Again, we’re harvesting water.”
Great care is also taken to avoid soil compaction and capping, in order to further limit run-off, he adds.
Monitored The Broadland Agricultural Water Abstractors Group comprises 170 agricultural and horticultural abstractors. Together, they hold licences to abstract 19m cu m of water.
The Broadland Agricultural Water Abstractors Group comprises 170 agricultural and horticultural abstractors. Together, they hold licences to abstract 19m cu m of water.
The crops are monitored from May onwards for irrigation requirements, with the help of weather stations, groundwater grids, scheduling services and an evapotranspiration gauge.
“We also rely of the Environment Agency’s river flows information when planning our water requirements,” Mr Papworth says.
Irrigating usually starts in June, using a boom irrigator. “It’s much more efficient than using rain guns,” he stresses. “Leaks and the irrigating of roads are now things of the past.”
Water use is reduced using the booms and there is better filtration of water to the roots. “Another bonus is that we’ve seen a 2t/ha yield increase since we switched.”
The key for growers next season is to be prepared, he says. “Do a water audit early on in the season, and send your operators on a water efficiency training course.” Equipment needs to be checked and serviced.
It is also important to continue lobbying for funding for reservoir construction, he says. “We couldn’t grow potatoes without irrigation, but farmers are a visible target when it comes to water use. There’s a general feeling that we got away with it this year – but we must show we are using it responsibly.”
RDS-funded water efficiency training courses are planned for the Anglia region next January and February, UKIA’s Melvyn Kay says. “Details will be on our website, www.ukia.org, when available.”