The Nelson City Council is introducing water restrictions from tomorrow, due to the lack of significant rainfall and dropping water levels at the Maitai Dam.
The stage one restrictions - which will apply to all urban areas, will allow odd numbered houses to use sprinklers on odd days only and vice versa for even numbered houses.
A council spokesperson said the restrictions applied to the use of sprinklers on gardens, lawns and orchards
Public parks and gardens are not affected by the restrictions.
The council said a long, dry summer has been forecast and water restrictions were needed now to ensure long-term water supply for essential use.
Several other regions around New Zealand are also struggling with water issues.