The potential effects of any possible rises in sea level on beach communities and extreme weather events on the district meant HDC would soon be forced to adopt policy and planning guidelines to manage future potential risk.
The report said climate change activism was transitioning into a mainstream concern and there was a growing expectation within the community that all councils had a climate change adaption plan.
It also said an integrated approach was critical to managing climate risks and that there needed to be an integrated approach on a national scale, at the same time splitting New Zealand into different climate zones.
Horowhenua was zoned in an area from Taranaki to Kāpiti.
Regional Council Horizons, in its forward planning document One Plan, had included giving consideration to the implications of a possible 30-50cm rise in sea level, and a three degree temperature rise in the next century.
That would likely lead to more westerly winds, more rainfall in the west and an increase in extreme weather events like floods, droughts and high winds, it said.
Horowhenua's own District Plan took into account the implications of coastal erosion, sea level rise, tsunami events and storm surges, flooding, drought and water shortages.
The report said in the next 30 years Horowhenua could see higher air and water temperatures with longer summers and shorter winters, and any warming would be greater during summer and autumn.
From 2050 onward, the district could expect more frequent heatwaves resulting in possible drought and fire danger, although there would be a decrease in the number of frosts recorded and snow on the Tararua Ranges, it said.
There could be an increase in storms and extreme rainfall events and an increase in rainfall in western areas brought about by an increase in westerly winds, which in turn could bring about an increase in landslides and soil erosion.
