Useful water-saving tool? Or has Cape Town gone dotty?

Big Brother is watching‚ and now you can too thanks to a controversial City of Cape Town online water consumption map.

Water-stressed city residents can use the map to check up on their neighbours’ water habits based on households’s municipal bills.

The website‚ formally launched on Monday‚ has already prompted a wave of social media comment – most of it negative.

However‚ the city council defended the initiative‚ which it claims is aimed at increasing residents’ awareness of water consumption.

“The potential water-saving benefit for all of Cape Town of making water consumption indicators publicly available outweighs any privacy issues at this stage of the crisis‚” said Zara Nicholson‚ spokesman for mayor Patricia de Lille.

“This behaviour-modification tool attempts to acknowledge good savers and encourage those who have yet to join the efforts.”

In a statement‚ De Lille said: “By making consumption information available‚ we believe it will assist residents and communities to better manage water consumption. It is crucial for everyone to play their part.

“The city will continue with extensive enforcement but it is not possible to police consumption at every household. The map is a transparent tool and will assist in actively managing and reducing consumption to avoid ‘day zero’ (when the city will start turning off taps).”

The map shows city erven and colour-codes them according to monthly water consumption:

• Dark green dot: household using less than 6,000 litres per month;

• Light green dot: household using between 6,000 and 10,500 litres per month;

• Grey dot: estimated readings when the water meter is not read for some reason‚ or if no information is available for the property.

De Lille said the intention was to make the map as green as possible‚ thereby encouraging compliance with the water restriction of 87 litres per person per day.

“The greener we go‚ the more we push day zero away‚” she said. “The map shows that many households across Cape Town are working hard to save water as part of the effort to get us through our worst drought.”

Nicholson said there was no breach of privacy involved in publishing the map‚ which will be updated monthly with the previous month’s consumption information.

“Water consumption data relating to property is not personal information and there is no legal obstacle to the city making it available at its discretion‚” she said.

“No indicators have been published for high-consumption households and the city is not naming and shaming.”

But ratepayer organisations and residents appear largely opposed to the map. Most felt it was divisive in that it created potential for conflict between neighbours and did not provide enough context. Households with no green dot might be assumed to be non-compliant when in fact their data had not been included.

“Not only daft‚ but dangerous‚” said one commentator on the popular Facebook page Western Cape Watershedding.

“Sincerely hope people don’t start harassing the ‘no dot’ group. The map isn’t an accurate representation of who is saving water for the ‘no data’ crew‚” said another commentator.

Ratepayer groups were also unimpressed: “We don’t agree with it – there will be a large-scale naming and shaming‚” said Gavin Smith‚ of the Greater Cape Town Civic Alliance.

“What the system lacks is context – you don’t know how many people are on each property or if they have an exemption.”

He said the large data gaps were problematic. Nor would residents respond well to the “big stick approach”.

Chris Willemse‚ Camps Bay Residents and Ratepayers Association chairman‚ said the city council should focus its efforts on obtaining useful data – such as how many people resided or worked on each property — rather than affixing dots to properties.

“I don’t know why they waste their time. Instead of trying to work out the details of the problem they mess around with this stuff‚” Willemse said.