Into the Jungle: hydroelectric power supply for mining in Sierra Leone

Darren Ainsley connects his laptop to a small grey box bolted to the stout trunk of a Eucalyptus tree. He brings on screen a plot representing the adjacent river’s water level recorded over the past four months, then asks the group of onlookers, “Was the water highest on September first?” He raises an arm above his head to indicate the approximate river level at the peak of the rainy season; over a month past. Our guide, Gladstone Cokar, translates the question into Temne, the language of the remote village in Sierra Leone we are visiting for the second time in four months. Gathered amphitheatre-style to view the laptop screen, the locals make animated conversation, a few shoulders shaking with guarded excitement. “Yes. September first,” says Gladstone, smiling.

Following a promising hydropower resource desktop study completed by Knight Piésold in early 2008, UK based Cluff Gold PLC hired Knight Piésold to undertake a hydrology study as a substantial step towards the design basis and proposal of a run-of-river hydroelectric power facility. The vision for this type of project is for the development of a symbiotic partnership between public and private sectors – local and international – to create employment and infrastructure improvements in the immediate short term while leaving legacy assets for the country in the long-term. The potential to couple hydroelectric power with mining – where energy for ore extraction and processing tends to rely on electricity generated in remote locations by burning heavy oil or diesel fuel – has long been a part of Knight Piésold’s consulting services. In the early 1920s, the company’s founder, Dr. Francis Edgar Kanthack, consulted for the Victoria Falls Power Company, established in 1909 to supply electric power to the growing South African mining industry. Today, in lesser developed countries like Sierra Leone, there remain obvious logistical difficulties in supplying remote areas with large quantities of fuel for generating electricity, in addition to important environmental considerations. Alternatively, private investment can facilitate construction of a hydropower facility, in turn providing the requisite energy for the life of a mining project and replacing fossil fuel combustion during production, and earn a profit on the initial investment before turning ownership and operation of the facility over to the local government. In this manner, financial risk is shouldered by private investors, while the country ends up with a legacy asset of hydroelectric power for the long-term development and diversification of the local economy.

The village of Jagbla lies on the banks of a wide, slow reach of the Teye River, at the foot of a series of large cascades and rapids. Like nearly half of the country’s population, the people of Jagbla are subsistence farmers. Mostly cassava and rice are grown for consumption in Jagbla, while the adjacent river and surrounding jungle are relied upon for fish and on the rare occasion, small game. This remote village of a few hundred people is an hour’s hike from vehicle access, on single-track jungle trail traversing streams and the occasional rice paddy. The route leads us through quiet, shaded groves of giant bamboo clusters growing several stories high, skirting the verdant hem of fertile sienna squares.

The Jagbla locals are warm, welcoming, and curious. The children erupt in a rolling choral cascade of “orpoto!” (Temne for “white man”) as news of our arrival spreads. There is much frantic waving of chubby hands and giddy laughter when we wave back with a smile. We are introduced to a sinewy, weathered old man, the Chief of Jagbla, and share a customary four-part handshake ending with a touching gesture of placing the hand over the heart. We sit and rest under the shade of the chief’s thatched palm roof, where the procession of local men and women hired to carry the piles of equipment and supplies have been waiting. A muted stillness fills the space between houses, the heavy air exerting a dulling pressure on the senses, the heat radiating from the hard orange earth underfoot. In this dizzying heat and humidity, the lagging foreigners are no match for the undulating hills of the country’s interior, despite being accustomed to long hikes over difficult terrain in the Coastal Mountains of British Columbia. The gumboots I didn’t have the heart to decline from our guides are now sloshing ankle deep in perspiration.

Knight Piésold’s current scope of hydrology work includes the installation of two streamflow monitoring stations and a data collection program to support a detailed hydrological analysis of two locations. Several return trips are scheduled to maintain continuous operation of the equipment, and to obtain flow measurements across a wide range of river conditions to establish a comprehensive stage-discharge (water level to flow) relationship. Meticulous attention to detail during this stage is essential: quality of the project’s financial analysis, design of facility components, and environmental impact assessment are inextricably tied to the quality of hydrometric data collection.

Somehow more remote than the Yele, the village of Magbogba is next on our itinerary. A six-hour drive from the Cluff exploration camp at the village of Baomahun, located near the geographic centre of Sierra Leone, gets us to the end of road access at the village of Madibi. From Madibi, we begin a four-hour hike through dense, steaming jungle, slash and burn cassava farms, and soaking rice paddies to arrive at Magbogba, a small farming village on the banks of the Pampana River. Passing through several villages en route, we stop to rest and replace fluids, shake the many hands extended in welcome, and self-consciously enamour over the playful antics of children. Walking through these villages is a continuous series of surreal vignettes: strapping women pounding grain with hefty palm logs; men yoked under five-gallon barrels of freshly harvested palm wine; gnarled elderly women and men defending sunning grains from hungry fowl; small children carrying infant siblings.

Despite Knight Piésold’s extensive international hydrology experience, each new field program is a learning experience requiring improvisation, tempered expectations, and attentive physical awareness. Safety plans are created in advance of travel and daily safety meetings take place to discuss emergency procedures, outline potential hazards, and address changing conditions. A new safety consideration discussed on this trip is how to prevent eager locals from putting themselves in dangerous situations while working around rivers swollen with heavy rainfall. Given our goal of engendering a sense of community involvement with the project, safe inclusion will be an accomplishment in and of itself.

Arriving in Magbogba a sweating mess of heat rash, my shade-oriented trajectory is diverted by a brightly clothed woman, directing me toward a wooden stool near the centre of the village. Soon, a dozen or more women are gathered around me, singing a call-and-response welcome song in layered harmony, swaying together and clapping in that contagious cross-rhythmic West African style. The experience is both rich and affecting in its symbolism and form, and I’m captivated. Darren arrives soon after, and the reflection of my amazement shines from his beaming face as he receives his own welcome. Unable to take in enough fluids to stay hydrated during the long walk, we are both feeling the effects of dehydration. In these conditions, the threat of water-borne parasites can’t keep us from our ablutions, taking turns cannonballing off a sturdy tree overhanging the village water hole. Not to be upstaged, a group of local boys scramble up the tree after us, diving gracefully under the shaded pond’s surface, emerging at impressive distances with ease.

Refreshed from the swim, we gather our equipment to visit our streamflow monitoring station several kilometres away. We arrive to find the station equipment has been torn loose by large debris during high flows, and the unease in the group is tangible. Despite a positive report from a site reconnaissance two weeks prior to our visit, the damage is not surprising. This location of the Pampana River, capturing a much larger drainage area than our station on the Teye, is expected to have a more prolonged and far greater magnitude seasonal peak. The downloaded station history suggests the seasonal peak has only recently passed on the Pampana River. Standing above the tumultuous water’s edge, we shout over the roaring waterfall in an attempt to discuss the damage and explain the situation to our hosts. The equipment cannot be reinstalled until the river permits safer working conditions, but we can still collect meaningful discharge measurements by comparing a water level survey against previously established permanent benchmarks – steel bolts installed nearby on various bedrock outcroppings. The benchmarks act as safeguards against precisely this type of damage, enabling consolidation of data collected before and after equipment damage or failure.

With darkness setting in, we feel our way back to the village along the steep jungle path. Racing to catch up with the group, I’m suspicious of yet again being the punch line of an inside joke after stopping to marvel at a brilliantly coloured tree-frog tucked into the nook of a warped branch in the underbrush. A small area in the middle of the village has been swept clear of various livestock droppings for us to pitch our tents. Now nearing the end of the rainy season, there is a nightly threat of torrential tropical downpour and we reluctantly tie down our tent fly, dreading its suffocating effect. The stagnant, heavy nights offer no respite from the sweltering days as the sun-baked clay radiates back a day’s store of heat. We eat a dinner of Spam sandwiches by headlamp, sharing what we have with an audience gathered to watch. The sound of a battery-powered radio cuts into the blended hum of evening conversation and crooning insects, and to my left three small boys begin moving to a driving dancehall beat. Soon, a village-wide dance party forms around us, our headlamps adding some ambiance as makeshift strobe lights. It’s not long before Darren and I find our courage and improvise self-effacing entrances to the dance floor, inciting shrieks of laughter over the crackling distortion of straining speakers. The universal consonance of music overcomes our dissonant languages and we jump around together under a densely starred sky of seemingly ancient clarity. After finally putting down for the night, a cricket discovers favourable acoustics under the fly of my tent. Later, one of the loitering group of bleating goats pees on my tent, and another nibbles curiously down a zipper seam. Barely audible over the electric pre-dawn din of insect life, I’m roused from a fitful rest by what must be morning call to prayer. I’m exhausted, but still brimming with enthusiasm for all I’ve experienced.

We wash down a breakfast of Spam and cheese sandwiches with a cup of hot water infused with a pleasing smoky aroma from damp kindling. A crowd of onlookers are on hand to observe the morning’s work. Knight Piésold’s newly purchased Acoustic Doppler Current Profiler (ADCP), an instrument especially useful for high accuracy flow measurements in large rivers, sits packed in an impressively robust case. A commanding presence at any airport, the case itself gives our trip more the air of a colonial hunting expedition than scientific research. While Darren and Gladstone grapple with explaining the rope system used to tow the ADCP back and forth across the 50-metre river crossing, I enlist the help of several young boys and girls to assemble a pontoon boat used to frame the measurement instrumentation. A few passes with the ADCP are enough to give us confidence in our results, but we have time to spare, and the impressive physical undertaking of the local men and women in getting us to this point presses us to continue. Throughout each pass of the ADCP, locals are gathered behind the laptop, intently observing real-time data forming a vibrant graphical representation of the riverbed profile and water velocity. Awe is projected by body language everywhere.

Following the successful field trip, we rest for the night at the Sierra Light House Hotel, built on the ocean’s edge of Man of War Bay, at the tip of the Freetown peninsula. After a deeply satisfying shower – cold – and a traditional Sierra Leonean meal of hearty groundnut stew and jollof rice, Darren and I make use of the hotel’s new WiFi service. Over the past two years, an in-house team of programmers at Knight Piésold have worked with scientists and engineers to develop an online data management system to securely store, organize, and neatly present all data collected in the field. The FULCRUM data management system allows project managers in Vancouver and our client in the UK to access and review the data collected over the past few days, along with photos, and provides tools to manipulate and print report-ready tables and figures via an intuitive web-based interface – before we leave the country. It also allows Darren and I to work as we’ve always dreamed: cold beer in hand, on a tropical patio overlooking the ocean.