Mr Howard said the lines' locations were mapped using GIS (geographic information system) technology.
District Neighbourhood Support co-ordinator Deborah Campbell said the lines made it much easier for people to be able to see where they needed to go in an earthquake emergency.
"People can get a bit panicky, and something visible like a line can make them feel that little bit safer in knowing that once they get past that point they are in a safer area," she said.
Hokio Progressive Association president Rose Cotter said the Hokio Beach Rd marking showed people the point to get past and was a very good visual sign for her community.
"We suggest Hokio residents keep going past it, at least as far as the golf course road, and keep moving inland," she said.
"I'm pleased the lines have been put in place and pleased we have more detailed signage at the beach as well as notices to give to residents."
Horizons' blue lines project follows a similar initiative carried out around Wellington seaside suburbs that has also attracted international interest.
Meanwhile, while the Hokio landfill was inside Horizons' tsunami line, he said it was outside the inundation zone and information suggested it would not be affected by a tsunami.