The Otago Regional Council is asking for help from boaties to prevent the spread of Didymo, or rock snot.

With summer upon us, holidaymakers are being asked to look after the southern region’s waterways by checking, cleaning and drying equipment after use in water.

The Check, Clean, Dry message comes from the Ministry for Primary Industries as part of efforts to restrict the spread of didymo.

ORC spokesperson Scott MacLean says keeping our waterways pristine is everyone's responsibility.