Keeping a wet-deck hydrated after a megafire

by Roger Parsons and Ritchie Morris
A devasting fire started on 7th June 2017 and swept through Sedgefield, Knysna and Plettenberg Bay, leaving a path of destruction in its wake until it could be contained four days later. Seven people lost their lives, more than 1 000 homes were lost or severely damaged and some 15 000 ha of commercial forestry was lost or damaged. Damage amounted to billions of Rands and the entire community had to rise up and build their lives again.

PG Bison was just one of many businesses that had to implement a rehabilitation strategy so that they, their people and those who depend on them for their livelihoods, could survive. As some of the damaged timber could still be harvested, they set about salvaging what they could. However, local sawmills could not cope with the sudden influx of timber to be processed, remembering that the Longmore Sawmill was also lost in the fire. To counter this, PG Bison set up a wet-deck on their Ruigtevlei property east of Sedgefield.

Wet-deck entails packing the logs in stacks 4.5 m high and 24 m wide and continually spraying the timber with water. The continuous wetting of the logs creates a shortage of oxygen in the wood, preventing fungi and fauna from entering and damaging the timber. If done within 10 months of the fire, the timber could be preserved until it could be processed. At its peak the wet-deck would extend for 3 km and need 4.5 ML/d of water for the irrigation.

PG Bison appointed Morris Environmental & Groundwater Alliance (MEGA) to develop a wellfield on their property to provide the required water. The prospects of meeting the demand were considered good given the groundwater supplies developed to the west for Sedgefield and the fact that the PG Bison property overlay Table Mountain Group (TMG) geology, known elsewhere as a productive aquifer system.

Ritchie Morris of MEGA quickly put together an experienced team of hydrogeologists and contractors to tackle the project, knowing that the clock was ticking to preserve the timber. A detailed geophysical study was undertaken to support the siting of eight production boreholes. Two dedicated monitoring boreholes were also installed, while a backup borehole was later drilled in 2019. Five of the boreholes targeted the shallow primary aquifer, while three were drilled to depths of around 100 m in search of the TMG aquifers.

In spite of limitations imposed by the diameter of casing available at the time, the boreholes were all high yielding. Scientific testing of the boreholes confirmed that collectively they could meet the estimated peak demand.

Just three months after the fire the Fairview Wellfield was brought into production as the first timber started to arrive. Initially, abstraction was limited, but commenced in earnest in early 2018 and steadily grew as the size of the wet-deck increased. Abstraction reached a peak of around 5 ML/d in June 2019, but has since declined as the size of the wet-decks reduced.

As of July 2021 abstraction has been negligible. Monitoring during production included the volume of groundwater abstracted and groundwater levels in the production and monitoring boreholes. A Water Use License was sought and granted by the Department of Water and Sanitation and the Breede Gouritz Catchment Management Authority.

Concern had been expressed by some local residents about the impact of the abstraction from the Fairview Wellfield on Groenvlei, in particular as a result of observed low water levels in the wetland. Groenvlei is a unique wetland 700 m south of the wellfield. It is only fed by rainfall and groundwater inflow, and has no influent rivers.

This concern prompted a review of available data by Dr Roger Parsons who was awarded a Ph.D in 2014 for his research into the groundwater contribution to Groenvlei. Monitoring borehole RV12 had been positioned between the Fairview Wellfield and Groenvlei for the express purpose of detecting and quantifying potential impacts. Comparing the water level data of Groenvlei monitored by the Department of Water and Sanitation to that monitored in RV12 showed that the hydraulic gradient between RV12 and the wetland remained (nearly) constant during the five year observation period. The implication of this is that the volume of groundwater discharged into Groenvlei would remain stable under these conditions. This assessment was supported by a lack of correlation between the period of pumping, the drawdown induced in the production boreholes and the water levels observed in RV12 and Groenvlei.

Water level graph 1: Relation between the water level in Groenvlei and that monitored in borehole RV 12 located 250 m north of the wetland, but 650 m south of the nearest production borehole. Total abstraction from the Fairview Wellfield is also shown.

By contrast, a strong correlation was observed between rainfall and the water level of the wetland. It was observed that the current drop in wetland started at the same time as the onset of drought in October 2015. A similar pattern of decline was observed during the drought experienced in the late 1980s and early 1990s.

Applying the cumulative rainfall departure method – a statistical procedure introduced more than 70 years ago and used in groundwater recharge studies – shows that from October 2013, the level in Groenvlei rose in response to above average rainfall, but then started to fall in October 2015. The good rains of January 2020 only temporarily interrupted the declining trend of the water level. Slightly more rain in late 2021 and March 2022 accounted for the recent upward trend.

Water level graph 2: A plot of the cumulative departure of rainfall from mean compared to the water level in Groenvlei and borehole RV12. Wetter conditions are experienced when the red line is above 0 (on the right-hand axis). Drought is apparent as of October 2015, coinciding with the declining water levels.

The observed relationship between the water level of Groenvlei and rainfall was expected given that rainfall accounts for 72% of the input into the system. While the wetland is recognised as a groundwater dependant ecosystem, groundwater is by far the lesser of the two hydrological drivers. Even so, monitoring the response of the aquifer to pumping from the Fairview Wellfield showed that the groundwater inflow into the wetland remained constant, during and after the wet-deck operation.

A positive outcome of this work was the additional knowledge gained about the groundwater resources of the area. Monitoring has shown groundwater was used within sustainable limits and that this provides an opportunity to further explore and develop groundwater supplies for either Sedgefield, Buffels Bay and even Knysna or for agricultural business purposes. However, exploration and use of what has been called the Garden Route Aquifer must be based on sound hydrogeological practice and management.

About the Authors
Ritchie Morris of Morris Environmental & Groundwater Alliance (MEGA) and Dr Roger Parsons of Parsons & Associates Specialist Groundwater Consults are professional hydrogeologists and registered Professional Natural Scientists. Ritchie was responsible for developing and monitoring the Fairview Wellfield while Roger has a long-standing interest in the hydrogeology of the area and the role of groundwater in sustaining Groenvlei. They wrote this article in their personal capacities. In doing so, they acknowledge the positive contribution of PG Bison, their commitment to ‘doing it right’ and permission to use their data in preparing this article.

The Cape sawlog PINCH!

The scramble for scarce roundlog resources in the Southern Cape has stakeholders on edge while government takes tentative steps to begin the process of bringing 22 000 ha back into timber production…

The timber industry in the Southern Cape has a long history that goes back to the 19th Century. We’ve all seen those grainy black and white photos of woodcutters felling and sawing huge indigenous hardwood trees in the natural forests around Knysna, George and the Tsitsikamma. The giant logs were hauled to the mills by teams of oxen where they were sawed up for use as building material, furniture, tools and implements, wagons and railway sleepers.

When the authorities eventually realised that the natural forests could not sustain the scale of the logging, they mercifully introduced management controls and then stopped it completely, placing the remaining natural forests in the region under conservation management.

To fill the void the government of the day as well as private entrepreneurs started planting pine to provide the raw sawlogs needed by the sawmills and countless downstream manufacturers and processors engaged in the timber industry, which by this stage underpinned the entire regional economy. The area under pine expanded from the Boland to Plettenberg Bay, and was concentrated around George, Knysna and the Tsitsikamma.

After 1992 government had a re-think about forestry and established Safcol to manage the state plantations on a commercial basis. A decision was made to lease out the 85 000 ha of Cape plantations via a tender process. MTO won the tender and took over management of the plantations in 2001 under a 75 year lease. Prior to this Cabinet made a decision to convert some 45 000 ha of the Cape plantations out of forestry into conservation and other land uses as these plantations were considered marginal and not commercially viable. In terms of the lease MTO was to hand back the exit areas as they were clearfelled at full rotation.

When a fire in the Tsitsikamma in 2005 destroyed some 16 000 ha of plantations, the volume of timber available for sawmillers and other processors in the region began to shrink as the gap between supply and demand became evident. This was the first of many blows that would erode the timber resources over the next 15 years or so. The roundlog shortage was exacerbated by the closure of plantations in terms of government’s exit strategy.

This prompted MTO and other stakeholders to start lobbying government to reassess its exit strategy, which they maintained had not taken into account the full socio-economic impacts that the exit would have on the regional economy.

Exit reversal
As a result Government appointed the Vecon Consortium in 2006 to re-assess the viability of the exit areas, which recommended that half of the exit areas – 22 000 ha – be restored to commercial forestry. Cabinet approved the exit reversal of the 22 000 ha in 2008.

Meanwhile the roundlog shortage began to impact on local timber processors with the smaller, informal mills going out of business first. Between 2005 and 2006 11 sawmills closed in the Cape. At the same time there were fears that the land being handed back to SANParks and other authorities was becoming a fire risk.

As the years rolled by, MTO as the incumbent managers of the state plantations tried various approaches to persuade government to allow it to re-establish and/or manage the re-growth of the exit reversal areas after clearfelling. At the same time community leaders and other stakeholders started applying pressure to stake their claims to the land. Bold decision-making and dynamic action was needed, but was not forthcoming.

In 2014 (six years after the Cabinet decision) a feasibility study for the re-commissioning of the VECON forestry areas was presented to the IDC. In May 2017 a land rights enquiry for the Western Cape re-commissioning areas for DAFF was presented to the Western Cape Forestry Forum.

In November 2019 DAFF and the Department of Agriculture, Land Reform and Rural Development put out a tender for a transaction advisor to assist with the development of a sustainable forestry business model in the Western Cape recommissioning areas.

In the meanwhile the 2017 and 2018 wildfires delivered a hammer blow to the region and put a huge hole in the sawlog resource, and skewed the age class distribution.

The urgent need to re-commission the 22 000 ha was identified as a priority deliverable in the Forestry Sector Masterplan, a part of the Public Private Growth Initiative backed by the president himself.

By this stage the shortage of sawlogs – especially the large B,C & D class logs required by the sawmills producing structural lumber – is reaching critical levels, raising tensions among stakeholders even further.

Some of these mills, like AC Whitcher and Boskor, are partially or wholly dependent upon MTO for suitable roundlogs to keep their mills operating at capacity. MTO has its own mills in George and Longmore to keep supplied with logs as well, so there is a conflict of interests at play.

Both Whitcher and Boskor (owned by Swartland Investments) are old, established family-owned Cape businesses. Their supply contracts with MTO have long since been curtailed and they are reduced to haggling over roadside auctions. Job losses are on the cards. Many smaller mills and pole manufacturers in the region are in the same boat.

Survival mode
“We are surviving for now … we are simply outbidding all the competition because we still can, but this is not sustainable,” commented Hans Hanekom, CEO of Swartland which owns and operates the Boskor sawmill in the Tsitsikamma. Swartland manufactures doors and windows in their factory in Cape Town.

“For now we are taking everything into the mill that we can - even rejects. We need mainly B, C & D class logs but can use the upper end of A class logs as well. Half of our pine business is for export. The commodity boom due to COVID helped us as prices climbed, but it is getting over now … we are hanging on for dear life. Sooner or later we will lose the export business because our raw log prices are too high – we are competing in this market with Brazil, Chile and Poland.

“There were 300 000 cubes of roundwood a year available in the Tsitsikamma … now its 200 000 cubes, and 100 000 cubes is being taken to George by MTO. We are buying the lion’s share of timber sold at roadside here in Tsitsikamma,” said Hans.

AC Whitcher is slightly better off as they have 1 200 ha of their own plantations in the Titsikamma, which supplies some 10-15% of the mill’s roundlog requirements. Another 25% of their timber intake is supplied in terms of a long term contract with MTO. For the rest they must compete with the open market for roadside sales.

According to Gene Ritchie who manages the AC Whitcher sawmill, they are over-harvesting their own plantations to keep their mill busy.

AC Whitcher sawmill employs 300 people and Boskor around 150 people.

PG Bison, which operates the large Thesens sawmill in George, is better off as they have their own plantations, although they also suffered losses during the recent fires.

Kareedow Kreosoot Werke (KKW) in E Cape is also feeling the pinch. They employ 76 people and produce 12 000 cubes to 16 000 cubes of SABS approved poles a year for domestic and international markets. According to branch manager Lelani van der Walt they are running short of poles for processing – especially the species that they need i.e. P. radiata. She said they were getting the bulk of their poles from MTO but no longer … the supply dried up around December last year. They also source poles from private growers. E. grandis is also scarce, she says, and they are trucking in raw poles from KZN.

“We knew there was a shortage looming, but the crunch has actually arrived – not just for us but for everybody including the small sawmillers. We have hope that we will continue to be able to source the right raw poles we need, if they plant up unplanted and burnt areas etc … I pray that something will come up, otherwise it is inevitable that jobs will be lost.”

The news that MTO is planning to convert 4300ha of forestry land to avocados has not gone down well with the sawmill lobby. Neither has the fact that, as at January 2020, 8.7% of MTO’s sustainable plantation area was temporarily unplanted – presumably mainly areas burnt in the 2017/18 fires.

According to the MTO Management Plan TUP will increase to 14% by 2024, whereafter it will reduce to 1.5% by 2029.

“It’s a dire state of affairs, and there are no easy answers,” commented Roy Southey, Executive Director of the Sawmilling Association of SA. “The small independent millers are really battling. Everybody has known the timber shortage has been coming for a long time, but now it’s critical.”

The pressure on the Department to get a move on and put the 22 000 ha out to tender is ratcheting up, and all of the stakeholders are positioning themselves to pitch hard for these plantations, which are expected to be offered in three or four packages.

Albi Modise, Chief Director of Communications for DFFE told SA Forestry that the process would begin during the 2021/2022 financial year.

He said that the preferred model will be for investors to partner with neighbouring communities, and that the leases would be for a maximum of two rotations.

MTO response
MTO CEO Greg Woodbridge welcomed the news that DFFE plans to move on returning the Vecon areas into timber production.

“We believe revitalizing the forestry cultivation on the Vecon areas is long overdue and will go a long way in enhancing the round log supply to the market. MTO attempted over an extended period of time to have the decision around exit plantations reversed, however we were not successful. Through ongoing engagements with DFFE we are in support of their plans of returning the 22 000 ha back to forestry. It is our opinion that this could have been done several years ago and the impending volume cliff could have been avoided. MTO stands ready to assist in whichever manner this initiative takes to restore the forestry industry in the area to previous levels that will benefit the local community and the industry,” said Greg.

“MTO’s operations in the Southern Cape have been significantly affected by fires over an extended period of time, however we continue to invest in our forestry assets to ensure we get the plantations into full rotation. The average growth cycle for our trees is between 18-22 years which gives us the clear runway for getting our plantations into full rotation and the timing to realize the maximum volume possible.”

The exit reversal areas are currently being managed for fire protection and alien clearing by the Forestry Support Programme and Working on Fire.

According to Braam du Preez of the Forestry Support Programme, there are pockets of trees in some of these exit reversal areas that have regenerated naturally and are growing well. This will give the new lessees a bit of a running start when they take over management of these areas, some of which have been lying fallow and unproductive for years.

In any event there is going to be a lot of investment required and a lot of work for local people when these areas eventually come back on stream!

*First published in SA Forestry Annual 2021