The Honolulu Board of Water Supply is undertaking a two-year project to electronically map about 46,000 valves, meters, hydrants and other features of its water system in public areas.

The city agency announced Monday that it has retained environmental and engineering firm Dudek to use global navigation satellite system technology to record location information for water system features across the island to make it easier to locate the features, especially when circumstances, like flooding due to a water main break, make locating features difficult.

“When completed, this project will enhance the accuracy of our (geographic information system) maps and save time and effort for our field employees who need to access valves and meters,” Ernest Lau, BWS manager and chief engineer, said in a statement.

The $500,000 contract with Dudek continues a prior mapping effort about 10 years ago using global positioning satellite technology that mapped most, but not all, of the agency’s water system features.

BWS said the new job will involve workers with special BWS contractor identification badges, business cards and letters placing an antenna over features, recording data in a tablet and sometimes taking photographs.

All work will not affect water serv­ice and will occur in public right-of-way areas including roadways and sidewalks. The agency also said that in rare instances it might need access to easements on private property and will notify property owners in advance that access is needed.