It's only a no-brainer as a last resort. Your number is preposterously low, and desal's environmental costs are pretty high. Where possible, conservation is a better plan.
Here in California, desalination runs about $2000-$3000 per acre-foot, so your number is more like $1.60-$2.40/1000 litres. (For comparison, I pay around $5/HCF for rainwater from my city, which is $1.70/1000 litres.)
And even that price doesn't include externalities. Desalination takes a huge amount of energy, and the salt doesn't just disappear. It gets pumped back into the ocean along with chemicals: http://www.paua.de/Impacts.htm
The Tuaspring desalination plant at S$ $0.45/m^3 in Singapore, 318,500 m^3/day. [1]. At 1233 m^3/acre foot, that's $399/acre foot. Not that useful for the central valley, because it's expensive to transport, but fine for the coastal cities.
The technology has advanced a lot recently, so older plants (or plants that were started a while ago), might be more expensive.
It's even cheaper just to recycle water, so that's another option in the toolkit for the California Cities.
Conservation has it's place, efficiency even more so, but for residential use, with a bit of planning, it's entirely reasonable for an individual to consume 200 liters/day.
Here in California, desalination runs about $2000-$3000 per acre-foot, so your number is more like $1.60-$2.40/1000 litres. (For comparison, I pay around $5/HCF for rainwater from my city, which is $1.70/1000 litres.)
And even that price doesn't include externalities. Desalination takes a huge amount of energy, and the salt doesn't just disappear. It gets pumped back into the ocean along with chemicals: http://www.paua.de/Impacts.htm