He said due to the earthquakes the land around the city had changed, causing some properties to sink and increasing flood risk.
"The earthquakes changed the profile of land around the estuary, rivers and creeks. Their profile has changed and has become susceptible in relation to sea level," he said.
"Imagine, if you will, five years from now and someone is thinking of buying in that area. The city council is calling to your attention as a purchaser that the site is at risk.
"Putting it on the title is the appropriate method for sharing what the council knows," he said.
But homeowners disagree and have called for Canterbury Earthquake Recovery Authority to buy their properties so they can get out.
They say having a hazard notice on their title will affect resale.
South New Brighton resident Anne Denton said she was worried that when she got her quake repairs done she would get a hazard notice put on her property and its resale value would be affected.
The Earthquake Commission recently contacted her, telling her repairs to her home were now on hold because they said she was in a "flood zone".
She feared when she does get repairs done and they require a consent, a notice could be placed on her property.
"I can't even imagine the value that will be lost because of having a hazard notice. Would you buy a house with that on it?" she said.
"We have been told our area in South Brighton is at high risk of severe flooding and all the houses around here need to be lifted 1.2 metres," she said.
She said the Government should give residents "a chance" and declare the area red zoned.
"How can you do that to people? Give us the option to get out first," she said.
A CERA spokesperson said Section 72 notices were applied across the country in a variety of circumstances where a hazard existed. In Christchurch, the flood risk also existed before the earthquakes.
"Where there is a rebuild, affected green zone property owners have the opportunity to consider mitigation options such as a raised building platform. EQC is currently working through land claims in greater Christchurch so property owners know their options," the spokesperson said.