Hunter Water's acting chief executive Graham Wood and executive drought lead Darren Cleary will address the media on Friday after Minister for Water, Property and Housing Melinda Pavey on Friday declared Level 1 restrictions will begin from Monday September 16.

The first level of restrictions mean residents and businesses cannot use standard sprinklers and watering systems, leave hoses running unattended, wash cars or buildings without a trigger nozzle or high pressure cleaner or clean paths, driveways and other paved areas with a hose.

The restrictions are enforceable, with fines of $220 for individuals and $550 for businesses who don't follow the restrictions.

A grace period of three months has been applied to restrictions in the Blue Mountains and the Illawarra, which are scheduled to begin on September 1.