Anyone working in an outdoor activity will understand that weather conditions greatly effect whatever they are doing.Right now we are in the middle of a storm - heavy rain over a prolonged time and strongish winds.
I recall several of these events and what happened around the Herbert/Waianakarua district.
The biggest event was the 1975 gales but I will address that at another time - here I will talk about floods.
At Herbert Forest, we took meteorological readings for the Meteorological Service and at one time I did a summary to find that the driest month of the year is most reliably June and the wettest ever month was also June. To summarize all this, I can only say that the North Otago (NZ for that matter) weather is dynamic. What seems to happen is that a depression/cyclone moves South and there is an anticyclone to the east. This cause the depression to move slowly and sometimes there is rain from the NE, then a lull but as the clockwise-moving depression moves South, the SE wind bring heavy dumps of rain and the so-called Southeasterly three-day drizzle. Usually on a rising glass (barometer).
One such event occurred in late 1968. One of the markers is Grave's Dam because it takes a substantial amount of rain to cause the river to flow over it. This happens perhaps three times annually. The other marker I have is my paddock which is on a small flat right beside the river. On a few occasions a stream flows through the gate and the bottom of bank on which the top terrace sits. This leaves a small island and when this happens, I have to check stock but the island has never been submerged as far as I know.
We had cleared a large area of Diamond Hill which had been planted in 1968 and this created a exaggerated runoff locally.
The 1 metre culvert on Couch's Road was washed out (we called the creek - Couch's but Alan Dick used the name - Glenburnie. I'm not too sure what might be 'official) . This flow also swept out the culvert/wet crossing on Breakneck Road and 'cleaned out' the creek-bed which is the loose boundary between the properties owned by Dr. King and Margaret MacKay.
All the roads through the forest were designed and built by local staff, and while perhaps narrow, we kept them maintained with the water tables and culvert kept clean. In heavy rain, gravel is carried down the water table and will block culverts. This cause damage to the road surface and has to be cleaned up. This done by a little bit of spade work, or a grader or if damage to severe the hire of trucks to cart fresh gravel onto the road. Sometime a lot of money can be saved if people go out when it is raining and turn the water off the road - people don't like getting wet though!
Mick Hill the dozer driver wanted to make a wet crossing where the culvert was washed out on Couch's Road, but I thought if we protected the fill, replacing the culvert would be the best option.
Mick had to drive way down the creek-bed to retrieve the 1 metre diameter concrete pipes - well me too because I hooked a strop onto them. The pipes were carefully placed and fill pushed over them. I had a team cutting Kanuka logs and we set them protecting the fill on the upstream side. Lacing them with No.8 wire and anchoring them with fence posts and tie back.
I was really pleased with the results and it stood up to the next flood!
However another 50 year flood soon after washed it out again! Mick was not around so I took the opportunity to drive the D6 and push fill into the creek so the water force would take the fill away. This was spectacularly unsuccessful and a porridge of clay was left in the middle of the creek.
I had to wait for the creek to go down and had another go. The road was about 2 meters above the creek-bed so I had to whittle that down and make a suitable approach on each side of the creek. The problem was, where to push the spare fill to. I needed to push it uphill thus not having the advantage of gravity. Once up the road a bit. I would push it over the side of the road.
I had not done much when I became bellied on a big rock in the creek-bed. The D6 had a logging winch on the back but in this case I would have preferred rippers. By forcing rippers and blade down, it is possible to lift the machine, pack rocks under the tracks and hopefully drive off. So I was unable to do that. But I could lift the front with with the blade. This was not enough as the ground beneath was so soft - all the rocks, logs etc did not lift the machine up enough.
My next trick was to use the winch. I attached it to a young radiata tree (maybe ten years old) but it simply pulled the tree out. So I wrapped it around five trees - they all came out too.
I was about to call some workers in to dig a dead man to use as an anchor when I remembered the railway iron. The piece of railway line was just a bit longer than the width of the tractor. I laced it onto the tracks with No8 wire and moved slowly in reverse. The railway iron kicked the dozer off the rock just as the wire broke and I was free!
Without further incident I finished the wet crossing and it server well until we started logging. The Waitaki District Council was prepared to give us one exit route and that was down Middle Ridge Road, so to connect that road to the Government Hill area, Couch's road was improved with an Armco culvert. To my knowledge this remains today.
Going back some time - a long time - Jock & Jessie Anderson used to farm land that is now forest (old Nat Stevenson's house). After the flood of 1980, he told me that he and Jessie had gone to the Herbert store on horseback. On their return trip there was water flowing over the bridge. Jock's horse walked across but Jessie's spooked a bit, so he waded back -the water was ankle deep - and he led it across. I thought that was very brave - I would never have done that!
There was another serious flood in 1980 with the main damage being the pond we had built at the bottom of Swallow's Creek burst and washed water around Cliff Blaikie's new house and left a lot of debris in the bridge. Cliff was faced with packing the scoured areas with river stones.
Cleaning up the pond was difficult and Mick became stuck with the D6! It was too boggy to pack stuff under it, so Bert Bennett came with his TD6 which had a blade and logging winch. The D6 was the heavier machine and this cause Bert's tractor to slide backwards, so he dug a pit and sat the machine in it much like a dead-man. Out popped the D6. And the pond was completed.
There are more houses along Reid Road now and I wonder haw safe that pond is. I will download some pics and one shows the Swallows Creek flowing into the river.
There were a lot of slips on the unstable Herbert Hill and the [silly] MOW tipped all the clay in the center of the river at Frame's crossing. So the river gravels could not scour and this caused a change in the bed which moved the river South poor old Allan Ross lost not only his crop of turnips but also his paddock!
By far the worst episode was in 1986 a 1 metre diameter log was left on top of the bridge! I guess it would take at least half a metre of water to carry it - maybe more. The damage in the forest was as might be expected but not excessive. The river was so high it swamped the Herbert/Waianakarua water scheme pump house causing it to close down.
The intake was filled with sand and we put two men and a Wajax pump there to help clean it out. Old Alf Milligan complained that the job was taking too long, but there was no other way with the resources available to us, and it was part of a corporate responsibility. It took a long time to get the scheme going again.
The present floods are bad enough but we do need regular floods to clear the river as there are many exotic weeds growing there. Buddlea, Gorse, Lupin, Old Man's Beard to name just a few.
I recall several of these events and what happened around the Herbert/Waianakarua district.
The biggest event was the 1975 gales but I will address that at another time - here I will talk about floods.
At Herbert Forest, we took meteorological readings for the Meteorological Service and at one time I did a summary to find that the driest month of the year is most reliably June and the wettest ever month was also June. To summarize all this, I can only say that the North Otago (NZ for that matter) weather is dynamic. What seems to happen is that a depression/cyclone moves South and there is an anticyclone to the east. This cause the depression to move slowly and sometimes there is rain from the NE, then a lull but as the clockwise-moving depression moves South, the SE wind bring heavy dumps of rain and the so-called Southeasterly three-day drizzle. Usually on a rising glass (barometer).
One such event occurred in late 1968. One of the markers is Grave's Dam because it takes a substantial amount of rain to cause the river to flow over it. This happens perhaps three times annually. The other marker I have is my paddock which is on a small flat right beside the river. On a few occasions a stream flows through the gate and the bottom of bank on which the top terrace sits. This leaves a small island and when this happens, I have to check stock but the island has never been submerged as far as I know.
We had cleared a large area of Diamond Hill which had been planted in 1968 and this created a exaggerated runoff locally.
The 1 metre culvert on Couch's Road was washed out (we called the creek - Couch's but Alan Dick used the name - Glenburnie. I'm not too sure what might be 'official) . This flow also swept out the culvert/wet crossing on Breakneck Road and 'cleaned out' the creek-bed which is the loose boundary between the properties owned by Dr. King and Margaret MacKay.
All the roads through the forest were designed and built by local staff, and while perhaps narrow, we kept them maintained with the water tables and culvert kept clean. In heavy rain, gravel is carried down the water table and will block culverts. This cause damage to the road surface and has to be cleaned up. This done by a little bit of spade work, or a grader or if damage to severe the hire of trucks to cart fresh gravel onto the road. Sometime a lot of money can be saved if people go out when it is raining and turn the water off the road - people don't like getting wet though!
Mick Hill the dozer driver wanted to make a wet crossing where the culvert was washed out on Couch's Road, but I thought if we protected the fill, replacing the culvert would be the best option.
Mick had to drive way down the creek-bed to retrieve the 1 metre diameter concrete pipes - well me too because I hooked a strop onto them. The pipes were carefully placed and fill pushed over them. I had a team cutting Kanuka logs and we set them protecting the fill on the upstream side. Lacing them with No.8 wire and anchoring them with fence posts and tie back.
I was really pleased with the results and it stood up to the next flood!
However another 50 year flood soon after washed it out again! Mick was not around so I took the opportunity to drive the D6 and push fill into the creek so the water force would take the fill away. This was spectacularly unsuccessful and a porridge of clay was left in the middle of the creek.
I had to wait for the creek to go down and had another go. The road was about 2 meters above the creek-bed so I had to whittle that down and make a suitable approach on each side of the creek. The problem was, where to push the spare fill to. I needed to push it uphill thus not having the advantage of gravity. Once up the road a bit. I would push it over the side of the road.
I had not done much when I became bellied on a big rock in the creek-bed. The D6 had a logging winch on the back but in this case I would have preferred rippers. By forcing rippers and blade down, it is possible to lift the machine, pack rocks under the tracks and hopefully drive off. So I was unable to do that. But I could lift the front with with the blade. This was not enough as the ground beneath was so soft - all the rocks, logs etc did not lift the machine up enough.
My next trick was to use the winch. I attached it to a young radiata tree (maybe ten years old) but it simply pulled the tree out. So I wrapped it around five trees - they all came out too.
I was about to call some workers in to dig a dead man to use as an anchor when I remembered the railway iron. The piece of railway line was just a bit longer than the width of the tractor. I laced it onto the tracks with No8 wire and moved slowly in reverse. The railway iron kicked the dozer off the rock just as the wire broke and I was free!
Without further incident I finished the wet crossing and it server well until we started logging. The Waitaki District Council was prepared to give us one exit route and that was down Middle Ridge Road, so to connect that road to the Government Hill area, Couch's road was improved with an Armco culvert. To my knowledge this remains today.
Going back some time - a long time - Jock & Jessie Anderson used to farm land that is now forest (old Nat Stevenson's house). After the flood of 1980, he told me that he and Jessie had gone to the Herbert store on horseback. On their return trip there was water flowing over the bridge. Jock's horse walked across but Jessie's spooked a bit, so he waded back -the water was ankle deep - and he led it across. I thought that was very brave - I would never have done that!
There was another serious flood in 1980 with the main damage being the pond we had built at the bottom of Swallow's Creek burst and washed water around Cliff Blaikie's new house and left a lot of debris in the bridge. Cliff was faced with packing the scoured areas with river stones.
Cleaning up the pond was difficult and Mick became stuck with the D6! It was too boggy to pack stuff under it, so Bert Bennett came with his TD6 which had a blade and logging winch. The D6 was the heavier machine and this cause Bert's tractor to slide backwards, so he dug a pit and sat the machine in it much like a dead-man. Out popped the D6. And the pond was completed.
There are more houses along Reid Road now and I wonder haw safe that pond is. I will download some pics and one shows the Swallows Creek flowing into the river.
There were a lot of slips on the unstable Herbert Hill and the [silly] MOW tipped all the clay in the center of the river at Frame's crossing. So the river gravels could not scour and this caused a change in the bed which moved the river South poor old Allan Ross lost not only his crop of turnips but also his paddock!
By far the worst episode was in 1986 a 1 metre diameter log was left on top of the bridge! I guess it would take at least half a metre of water to carry it - maybe more. The damage in the forest was as might be expected but not excessive. The river was so high it swamped the Herbert/Waianakarua water scheme pump house causing it to close down.
The intake was filled with sand and we put two men and a Wajax pump there to help clean it out. Old Alf Milligan complained that the job was taking too long, but there was no other way with the resources available to us, and it was part of a corporate responsibility. It took a long time to get the scheme going again.
The present floods are bad enough but we do need regular floods to clear the river as there are many exotic weeds growing there. Buddlea, Gorse, Lupin, Old Man's Beard to name just a few.
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