Tunisia has raised its drinking water prices by up to 16%, the official gazette said on Friday, in response to a drought that has lasted five years. After years of drought, average rainfall has increased in recent months but government officials said this week that Tunisian dams have only reached 35% of their stock capacity. The North African country last year imposed a quota system for drinking water and a ban on its use in agriculture. Since last summer, it has been cutting off water supplies at night. The price of water will be unchanged for small consumers. Those whose consumption exceeds …