A 500-plus strong crowd of residents opposing a major residential development at West Byron voiced their concerns at Saturday's Reclaim the Bay protest rally at Railway Park.
A consortium of developers proposes to construct 1100 houses that could potentially be home to 3000 people and businesses, on a 108-hectare site off Ewingsdale Rd.
Granting permission for the development rests in the hands of NSW Planning Minister Pru Goward, after Byron Shire Council rejected a motion to defer the rezoning of the site in May.
Byron Resident Group President Cate Coorey said thousands of locals and people from all over the world are concerned about the impact of the development being approved.
She said the 11th-hour rally sent a strong message to Minister Goward that Byron Bay residents don't support the development.
"The concerns are firstly the traffic that developers propose to build 1100 houses plus businesses onto a road that is already severely overstretched and crowded," she said.
"People are also concerned that there is core koala habitat on the site that will be built on and destroyed."
"This will end up closing off a koala corridor that's essential for breeding."
Soil concerns and pollution of surrounding waterways are also paramount in protesters' minds.
"The site is 75% acid sulphate soil, which, when dug up oxidises the soil, then you have sulphuric acid and heavy metals in the runoff," Ms Coorey said.
"The site is on a drained wetland, so any development would be very damaging to the estuary, which is a breeding ground for fish in the Cape Byron Marine Park.
"Pru Goward is looking at increasing the population of Byron Bay by roughly 30%, without coming here to see it (the site)."
Delta Kay, representing the Arakwal people, spoke out against the development, as did Greens candidate Tamara Smith and Labor pre-selection hopefuls, Paul Spooner and Keith Williams.
Ms Coorey said Byron Bay Mayor Simon Richardson described the proposed development as 'a monstrosity'.