sxshentai"

Blog

Joyabaj Fieldwork

Joyabaj Fieldwork

January 20, 2016

Authored by Andrew Carr, a structural engineer in the CH2M Glasgow office who is volunteering his time in the role of structural engineer on the Engineers Without Borders Joyabaj Dam Recommissioning Study in Guatemala with the CH2M Foundation.

Intake dam (for scale note Yan sat on the headrace channel on the right)

Intake dam (for scale note Yan sat on the headrace channel on the right)

So Thursday and Friday (January 14 and 15) were pretty busy days for me; we had two days to cram in structural inspections and scope out remedial works for the Joyabaj civil works, which were bigger than I’d expected. Briefly for those interested, there’s an intake dam which feeds water into a headrace channel, a forebay tank plus an overflow spillway, the penstock, the powerhouse building, and a tailrace. So a lot to do, but luckily I had the help of fellow CH2M volunteers Nason and Jan; both very experienced and capable guys. 

Headrace channel clinging to the cliff

Headrace channel clinging to the cliff

Just getting to the dam was a bit of a challenge; you have to walk up the headrace channel which clings precariously to the cliffs around 50 foot above the river for about 400 meters. Once there, we’d planned to take a swim in the reservoir and use a GoPro camera to get what information we could on the dam (the drawdown system was broken), but when we were told three communities dumped their effluent straight into the river upstream we weren’t so keen. We scratched our heads for a bit, then Mike turned up and in typical dedicated fashion, volunteered to go in and whipped his swim trunks out. He used a bamboo rod to probe for scour holes and took some underwater camera footage of the upstream face. 

We then set about assessing the condition of the headrace channel. To get the access we needed I made my way down the river itself (I needed to see what condition its formation was in). So I was basically canyoning my way down the river channel, scrambling up the riverbanks where I could to get close to defects (all pre-approved by Jan in the H&S plan of course). Great fun!

Mike searching for scour holes

Mike searching for scour holes

Mincho and Andy

Mincho and Andy

Identifying defects was the easy part. What I struggled with is scoping out remedial works, which is where Mincho came in. Mincho is a Guatemalan contractor who Mike has known and worked with for about 10 years on numerous water and bridge projects. His practical knowledge of how things get built in rural Guatemala, and what it costs was vital. With his help (for which I am extremely grateful – we showed our gratification by signing his tape measure) we were able to deliver a realistic price for the civil works remedials.

 

Go back to blog list

Share this article

nav_3 nav_1 nav_2 nav_4
2-41
January 2016

Leave a comment

Subscribe

RSS
contact us