Colombian oil producers in the Llanos Basin pump far more water than oil. The percentage of water they produce is going to get ever-more dramatic in coming years, as the oil runs lower and what is called “water cut” gets higher. State oil company Ecopetrol, which has some of the biggest llanos oilfields, is now trying all sorts of ways to turn that water into something useful, such as irrigating forage for cattle and irrigating water-hungry lumber trees. They are improving treatment for the water they dump into rivers and they recently built their first injection well.
They are pumping the water into a wet landscape, and the aquifer they are pumping from is so full of water that in decades of oil production in the area, the water pressure has dropped about 1%, according to engineers who briefed me and another reporter in August (yes, took me a while to post this). So this is not one of those cases where the environmental impacts are obvious and horrifying.
Rather, what jumped out at me from the presentations we saw there was the epic scale of water production that Ecopetrol has planned. Here are charts of oil and water output projections for four fields in Ecopetrol’s Central Region. These are all in the llanos department of Meta, and almost all of these plans are in the Cubarral block, which includes the company’s biggest field, Castilla, as well as Chichimene, Akacias and a new exploration area called CPO-9.
The top chart shows how current wells are declining. Without massive new investment, the field will taper off, as in purple. With massive new investment, it can increase output before tapering off a bit more slowly, as shown in green.
The second chart shows water output. The skinny dark blue strip at the bottom is water output in the ield as it stands today. The light blue mountain on top of that is water output if the investment plan is fulfilled.
To put this in real terms, water output in this one region for this one company would peak in 2018 at 4.12 million barrels a day – 98 million gallons a day. At current Colombian urban consumption (131 liters a day per capita), that would be enough for a city of 5 million people, or 10 percent of the country’s population.
And all this doesn’t even include any new water production in the many non-Ecopetrol projects in the region. Note that Pacific Rubiales, which operates the very successful Rubiales field, had to hold back oil output in the first quarter of 2012 as it waited for permits to increase its water disposal rates.
What is perhaps most surprising about this is how the water production stays high over the years, while oil production tapers off. Ecopetrol is going to have to deal with more and more water for every barrel of oil.
I have no idea what will be the long-term impact of taking that much water out of the ground. Anyone who happens to know, feel free to write in.