What will it take for Cape Town to recover from the drought?
Whether the rains return or not, there are troubled times ahead.
With Cape Town in the grips of its worst drought in over a century, fear has spread about Day Zero – now pegged at May 11 – when the taps will run dry.
But this is just one aspect of it.
What will take it take for the mother city to recover and, if the rain comes, can we say that the drought has lifted?
At best, it could take three years for the drought to end.
At worst, we will head into an unprecedented disaster.
Thanks to climate change, we don’t know when the rain is coming – but either way, the ecosystems that keep it all in the balance have taken a hammering that can outlive the drought itself.According to Professor Robert Scholes, a systems ecologist at the University of the Witwatersrand, the best-case scenario is a three-year recovery period – and that will only happen “if we get normal rain going forward”.
If the rain comes, it will bring relief, but it won’t solve drought-related problems.Normal rainfall will “recharge the aquifers and refill the dams”, but at this point it is not possible to say if the rain is coming.An aquifer is a layer of shattered rock (beneath the soil) that allows water to run through it.
According to Scholes, the Table Mountain range has high-quality aquifers, “but these have been badly depleted over time” and the “underground tanks” that form within the system are very badly depleted.
In the past, we could use “statistical models” to predict rainfall. But, “with climate change, these circumstances have changed and thus shaken our confidence in making predictions”.He says the fear around “day zero” when the taps run dry is valid, and “we should all be screaming blue murder” about the prospect of that day coming.But, beyond that, there is the major issue of sewerage.“Water for the sewerage system is a big challenge” that is overlooked in the hype of the taps running dry, he said, while the “rising demand for water” in Cape Town had also reached crisis point.
He said internal migration had put pressure on the water availability in a way that was “never anticipated”, and that even if the city “survives one crisis”, it had to rethink the way forward.
“Even without climate change, there would be a crisis,” he said.
Another issue is that even when rain starts to fall, plant life – a fundamental part of the eco-system – has to catch up.
This means that if Cape Town is hit with another drought soon after the current one, the impact is exponential.According to scientists at the Carnegie Institution for Scientists, Anna Michalak and Yuanyuang Fang: “If another drought arrives before trees and other plants have recovered from the last one, the ecosystem can reach a tipping point where the plants’ ability to function normally is permanently affected.”
They said research generally focused on “the amount of rain and other precipitation that ends the deficit of water”, but the restoration of normal plant function is also crucial for recovery.
They said that recovery time from droughts increased during the 20th century, and during the 21st century, “more severe droughts will occur with greater frequency” – making incomplete drought recovery “the new normal”.
If Cape Town faces a second drought, it could be “harder on the ecosystem and push it off a cliff”.