Yesterday afternoon, after consultation with engineers, President Ricardo Martinelli authorized the reopening of the single standing span on the Interamerican Highway over the Rio Piedra to east-west traffic though, from different sources I’ve read, there are some restrictions on heavier vehicles requiring them to take alternate routes for the time being.
Last July I ran a post where I did some crazy math regarding rain water and how it relates to weight and volume. In light of Monday’s devastating rainfall that caused the collapse of several bridges in the area and the deaths of several people I thought I’d do some calculations on what just happened. For those readers who are into the metric system you’ll just have to work out your own math for this.
When it’s said that an “inch” of rain has fallen it means that an acre of land would be covered with one inch of water. According to the U.S. Geological Survey that’s 27,154 GALLONS!
According to Arturo Alvarado, director of Civil Protection System this area received 164.7 mm of rain in just two hours. That 164.7 mm is 6.48 inches. So, in just two hours each acre of land around here had 175,957.92 gallons of water dumped on it. There are 640 acres in a square mile so in two hours each square mile received 112,613,068.8 gallons of rainfall. Thats ONE HUNDRED TWELVE MILLION, SIX HUNDRED THIRTEEN AND SIXTY EIGHT POINT EIGHT GALLONS, FOLKS!
It’s about 23 miles from the Interamerican Hwy to Potrerillos Arriba. Going up to the mountains behind us add another five or six miles so let’s just give it a round figure of 30 miles. Taking a rough guess looking at Google Earth it’s about 15 miles from Potrerillos Arriba over to Volcan. The bridge in question is roughly half way between the two points but down much lower. So, we’re looking at an area of roughly 450 square miles. That would mean that in two hours the area received roughly 50,675,880,960 gallons of rain water. Fifty BILLION, six hundred seventy five MILLION, eight hundred eighty THOUSAND, nine hundred and sixty gallons. Staggering.
There are about 600,000 gallons of water in an Olympic-sized swimming pool. The two hours worth of rain that fell just in the area I’ve outlined would therefore fill approximately 84,460 Olympic swimming pools.
Now, aren’t you glad you know that?
One More Good Adventure 
Hello Richard:
Thanks for sharing your water calculations and dramatic pictures of the heavy rainfall in Chiriquí. All three blog posts are first-class journalism.
Don’t get wet.
Omar.-
Doing those calculations just go to show that sometimes a person simply has too much time on their hands and a weird mind.
That 50+ billion weighs about 442,636,847,260.4 pounds or 221,318,423.6 TONS!
Dats a lotta agua mon. No wonder de bridge she broke!
That’s a good guess, amigo, but it’s only a guess. Clean fresh water weighs 8 lbs per gallon, but this stuff was filled with mud so it had to weigh in at a lot more. I was going to do the calcs for the weight of the water, mentioning the additional weight added by mud, but it slipped my mind.
Thanks for doing the math.I went over to the house in Boqueron today to see for myself what damage the little river by the house had done. Normally the water is almost crystal clear but today, nearly a week after the storm, the water continues to be the color of coffee.
P.S. When are we going to see an addition to your blog?
One additional bit of math to add to the area calculations, from Volcan down to the bridge is about a 4% grade and most of it drains into the Piedra/Chico rivers. At the point where the bridges cross the river, the channel narrows adding to the depth and flow rate. The amazing part is that the bridge lasted this many years.
jim and nena
fort worth, tx
PS, my first post here, thanks to Omar for finding yet another great blog on Chiriqui.
Thanks for stopping by and taking the time to leave a comment.With this whole province backed up against the Continental Divide the whole area is a watershed and all that water has to go somewhere.
My first Chiriqui flood event was 1970; the bridge in Boquete was washed away then. I have great respect for water strong enough to move house-sized boulders.