An expressway west of Levin, the preference in recent public submissions, conflicts with a previously officially-stated preference for an eastern route.
A new and previously unreleased planning map showing route options all around Levin is also adding further uncertainty for highway residents already worried about their properties' future after years of delays and plan changes by the New Zealand Transport Agency.
NZTA has championed a bypass east of Levin, saying a western route had too many environmental, social and cultural issues, and an eastern route was more appropriate for an expressway.
It has publicised its preference for an eastern route down Arapaepae Rd and linking back to SH1 near Roslyn Road.
Following its recent Horowhenua expressway consultation, NZTA said 95 of 217 feedback forms wanted the expressway west of Levin, while 32 wanted it to the east and 86 expressed no preference.
NZTA said it would consider routes west of Levin, but it is understood an eastern route is still preferred.
At a community engagement session in June in Levin, NZTA staff told members of the public the agency had been investigating an eastern route.
Submissions supporting a western expressway favoured its shorter, more direct route.
Manakau SH1 resident and independent general election candidate for Otaki Sam Jennings said the expressway should be to the west and near the coast to avoid homes and productive farm land.
"An eastern route is likely to mean hundreds of homes bulldozed, lives disrupted, productive land taken, lifestyles and dreams ruined," he said.
He said he was uncomfortable with NZTA's process of involving just a few, select members of the community to choose corridors for the road.
A copy of a previously-unreleased NZTA map, intended for participants in NZTA planning workshops, has been put on Facebook by Mr Jennings.
The map shows a range of route options.
They include one west of Lake Horowhenua, one close to the eastern side of the lake, and two to the east of the town.
It also shows six options for routes approaching Levin from the south between Otaki and Ohau.
NZTA plans to publicly release final options late next month. The final route is expected to be confirmed early next year, with construction expected to start in 2021.
The four-lane expressway is proposed to run from just north of Otaki to just north of Levin. NZTA is also considering extending it to just south of the Manawatu River.