The police dive squad is joining the search for missing Christchurch builder Michael McGrath.
Police say investigations are now turning to a number of waterways in Halswell.
Detective Inspector Darryl Sweeney said the divers would complement the land search in the Christchurch suburb.
Sweeney also said police expected to finish searching a property of interest on Candys Rd tomorrow.
This week police released new security footage of McGrath leaving the Halswell New World on May 19 and 12.38pm.