The Stellenbosch municipality will also introduce Level 4 water restrictions from June 1, with exemptions available on application for the town's important agricultural and nursery industries, it announced on Thursday.
This is after Western Cape Premier Helen Zille declared a drought disaster in the province last week and Cape Town indicated it would go up to Level 4 restrictions.
Most of the Stellenbosch municipality is engaged in wine production, according to Statistics SA.
It includes the towns of Stellenbosch, Franschhoek and settlements such as Klapmuts, Koelenhof, Kylemore, Johannesdal, Pniel, Jamestown and Raithby.
The municipality said that the Level 4 restrictions ban any irrigation with municipal drinking water.
However, nurseries and customers in agriculture or historical gardens could get an exemption.
Residents who use borehole water, treated effluent water, spring or well-points to water or irrigate their gardens, must display clearly visible signage indicating the source.
The National Department of Water and Sanitation also requires all boreholes and well points to be registered with the local municipality.
From June 1, customers will not be allowed to wash vehicles, trailers, caravans or boats with municipal drinking water.
The same applies to businesses and formal and informal car washes, unless they have applied for and been granted permission. If they get permission, they have to use recycled water.