The March weather bomb:
On the 29 March Northland had a “rain bomb” that caused widespread damage, severe in certain localities. Approximately 400mm of rain fell in the Hikurangi Swamp Scheme catchment area within 24 hours, the drainage system was not able to cope and the stop-banks were breached. A typical severe weather event causing breach of the stop-banks normally deposits a maximum of 15-20m cu.m of water into the swamp pockets. Four times that amount was deposited on the 29 March, making it a 1-in-150 years event.

It took two weeks for the flood waters to subside and about 4000 hectares of pasture were destroyed and needed resowing. Damage included:
• Stock losses through drowning (fairly small).
• Loss of production owing to immediate drying off of milking cows.
• Loss of pasture.
• Damage to plant and equipment, especially water supply equipment.
• Damage to farm buildings.
• Silting and flood damage to pastures, fencing, water supplies, access tracks, culverts.
• Loss of grazing due to severe silting of land.

An assessment of costs carried out by Charmaine O’Shea for the Whangarei District Council put the average uninsurable loss at just under $1000/ha.

The July storm:
On 10th July heavy rain and gale force winds buffeted Northland, causing widespread damage estimated at $60 million. Flooding was slightly less but wind damage rather more on the Hikurangi swamp.

Evan & Sherleen Smeath’s story
The Smeath’s farm has a total area of 167ha including a milking platform of 105ha, 11ha in bush and trees and the rest used as runoff for young stock. The terrain ranges from swampy wetlands through fairly flat but flood-prone pastures, safer productive areas and some hills. With conservation and beautification in mind they have, over the years, fenced off drains, swamps and areas that are too steep for sustainable grazing. Some hillsides they have left in native kauri bush, while others planted in silky oaks, C. Lusitanica, Leyland cypress, blackwoods, poplars and eucalypts.

“Apart from the pines, which should give us some earlier income, and some gum trees for firewood, all the rest are for the distant future,” says Evan.

“By the time they are ready to harvest chemical preservation of timber will probably be a thing of the past, so we have gone for wood that doesn't need to be treated – you can just mill it and it is ready to be used.”

That indicates something of the Smeath’s farming philosophy. Their vision has always been to have a top Jersey herd and a top dairy farm run sustainably. Over the years they have made good progress – their property has hosted many research trials, and they have taken advantage of the results to improve pasture and animal productivity steadily. They have also “gone the extra mile” in reducing the environmental impact of their farming system by careful management of soils and fertilisers.

Earlier this year in recognition of their achievements the Smeaths were named the Supreme Winners in the Northland Ballance Farm Environment Awards. Not only did they win the overall Award, they also won the Ballance Nutrient Management Award and the LIC Dairy Farm Award for their fertiliser and breeding management programmes.

However, their journey towards achieving their vision came to dramatic halt in March, as Evan explains:

“Last season we ran 262 cows on the 105 milking hectares. I was expecting to do about 92,000 kg and at the end of March we were at just under 90,000 kg. Then on the 29th a weather bomb hit us and we got about 260mm of rain in about four hours. It was incredible, the biggest flood I have ever seen and I have lived here since 1964,” he says.

“At the peak of the flood we had about 70 ha under water, and much of it remained there for about 10 days. After four days the grass was dead anyway because it was so warm at that time, and we ended up regressing 64 ha.”

It could have been worse. The Smeaths were fortunate in that on economic grounds they had made the decision to change from autumn calving, which they had done for a decade, to spring calving. As soon as the storm hit Evan decided to dry off the herd immediately.

“We gave them dry cow antibiotic therapy and for the first four days they got about half maintenance rations to make sure they went dry. After that we were able to strip graze them on higher ground, and we sent 30 yearlings off the farm for grazing,” says Evan.

“There was a major cleanup job to do picking up all the rubbish before machines could go over the ground – logs, sticks, plastic bags, bottles, silage wrap, needles, syringes, you name it, it was there. Shirleen and I and the whole family got stuck in and worked from dawn to dusk for six days.”

Once the flooded area was dry enough Evan mulched any long grass, power harrowed the whole area, then seeded it using two roller drills with a set of chain harrows in between. The first drill rolled the ground and put in the seed and in the second drill compacted it. That approach combined with warm temperatures resulted in a very good strike.

As a result of grass seed trials that a seed company had been running on the higher parts of the farm trials for the previous 15 months, Evan was aware of three varieties that were top performers for his conditions . He sowed those varieties in the areas that are seldom flooded, and put a cheaper ryegrass/clover mix in the flood-prone areas.

From seed to feed took about 30 days, and six weeks from the weather bomb Evan brought the young stock home and grazed them on the regrassed area.

“We had put on a fine particle N/S mix with a helicopter and that combined with warm temperatures got the grass really moving. By that stage we were heading back towards ‘normal’, building up a bank of feed ahead of the herd and getting well set up for the winter with the cows were in good condition,” says Evan.

“Then we got hit with the second storm on 10th July. The winds were so severe that one barn was completely blown away and another one had a couple of gum trees fall down and cut it in half. It was worse than Cyclone Bola. We got over 200mm in a four-day period and the power was out for three days, and we had just started calving.”

Losing power meant considerable ponding because during floods the drainage scheme relies on pumps as well as gravity to get water away. When the power came back on the pumps were unable to cope with the backlog and continuing rain. Initially about 60 ha were under water but that dropped to about 30 ha. It took 12 days for the flood waters to recede.

Fortunately no calves had been sent off as bobbies, so Evan put them in on the in-milk cows twice a day. Then a neighbour managed to get a portable generator wired into his dairy Evan was able to do one milking there.

By the time the power came back on about 15 cows had calved but the pressure was still on. The Smeaths were also in the process of rebuilding their dairy and were flat out doing the base work. The storm put pressure on all the contractors, electricians and so on, who couldn’t get to the Smeaths to finish off the dairy.

“So we were going like hell to finish the cowshed, cope with the flood, cope with calving, and it was madhouse I can tell you. Even when the power came back on I was unable to get code of compliance for the dairy,” says Evan.

“It wasn't until the 21st July when we had 104 cows calved that I was finally able to put the milk into the vat. In the meantime I had been storing it in all the drums I could find, along with a colostrum preservative. So it was just a chain of events really that made everything stretch out, and it was a huge relief when we could finally get the tanker in.”

After again having to pick up and remove all the flood debris, Evan grazed the dry cows over the paddocks, then mowed the residue and put on fertiliser – it was too cold and wet for sowing seed at that stage. He expects some of the annual grasses and clover to come away, but so will the weeds, and he will have to regrass much of the area.

The lack of grass has meant the expense of buying in feed.

“This season we had aimed to milk 280 but we are down to 272. We are feeding them about 1.5kg of tapioca per day along with 5kg of maize silage and so far they are milking well,” says Evan.

“We are also feeding double the normal amount of magnesium supplement to combat grass staggers probably brought about by the cold, wet weather plus eating silted grass.”

The crunch period for feed is right now (late August). Evan hopes the herd has enough condition to take it through to mid September by which time the spring grass growth should catch up with demand.

What of the future?
With global warming and the likelihood of more frequent heavy rains, how will the catchment area cope? First, the District Council is to check that the pumps are sized correctly and working to their best efficiency, and look at the possibility of extra gravity gates. Second, Evan believes it would be well worth the cost to have spare feed on hand, perhaps a stack of silage.

“The first flood cost us about $75,000 in lost production, cultivation and regrassing, re-fencing, replacing culverts that got washed away, putting metal back on races, cleaning silt out of troughs, and so on. The second flood is going to cost us over $30,000 in terms of replacing barns and re-grassing etc, but we don't know at this stage how much production we will lose over the rest of the season,” he says.

“I have a gut feeling that we will be down 8000 – 10,000 kgMS. We have been fortunate that the end of season payout has lifted a little and future payouts look very promising.”

“Having two floods in quick succession has halted progress, but our vision is still in place and we should be back on track by November. However, but it has given us a bit of a hiding and makes us respect Mother Nature and be grateful for what we have. “

Evan acknowledges the extraordinary efforts by Council and power company staff after the storms, and also the help from Dexcel and Fonterra staff, and Task Force Green people for helping to clear the land of debris.

“It has also been great to have friends and family ring up to see how we are going, keeping in touch, and the whole farming community is united, everybody helps everybody else. They have been really magic,” he says.

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