Where do red or blue colour-coded drains actually go to?

Where do red or blue colour-coded drains actually go to?

During a visit to a manufacturing plant the other day, I was pleased to note that the drains were all clearly marked with blue and red paint. As you may be aware, this is a fairly standard means of colour-coding, so I knew what it meant.

However, the operatives I spoke to didn’t know what the colours meant.  Do you and your employees know where different drains go to? Do they understand the implications?

I loved these drain covers I saw in Vancouver, which make it absolutely clear that the drains lead to a local fish habitat.