"Inclusion of this property on the map does not imply the public has access to your property but as the land has been purchased by Auckland Council and will become part of the park in the future it has been included in the map," said the letter.
"We don't have a firm date for the house removals but it is likely to be at the end of 2015 or during 2016."
Auckland Council sports and parks manager Mark Bowater said the council had bought homes in Korma Rd between 2006 and 2011 under a strategic plan to develop the park. He said it could be some of the properties would be needed for carparking and a new playground. All residents would receive formal notification from the council to move out either later this year or next year.
But at least two residents who have lived in the modest brick-and-tile units for several years said they did not receive the letter.
One resident with a young family said he shifted in recently with a view to staying long term. He claims he was not made aware by the letting agency the unit was subject to a monthly tenancy agreement.
He now faced an unexpected headache of finding a new place for his family. "I thought this would be a long-term thing given it was council owned and there's an obvious need for social housing."
Bowater said all affected residents held monthly tenancy agreements and were not part of the council social housing stock. "There is no obligation to rehouse the tenants."
Mangere Budgeting Services CEO Darryl Evans said losing housing for carparks was disgraceful. "Where are these 40 people going to go? Len Brown and the council need to rethink this one. There has not been enough thought into this decision."
Evans said the biggest issue faced by people requesting help was high rents fuelled by a shortage of housing stock. "For the council to do away with that number of houses at this time is disgraceful."
Meanwhile, 25 pensioner units at nearby Liston Retirement Village in Delargey Ave on the opposite side of the reserve are also under threat.
The village, owned by the Auckland Catholic diocese, could face demolition for parkland under a long-term plan for the area. Puketapapa board member Michael Wood said the local board was commissioning a report to investigate options to retain the village.