The sculptor and environmentalist en' />

Auckland artist Barry Lett wants Upper Queen St and Myers Park turned into one of the world's great gardens.

The sculptor and environmentalist envisions the area between the Auckland Town Hall and Karangahape Rd having cascades and pools of water set among courtyards, pavements and landscaped gardens.

"Over time, this area would be transformed from its present traffic thoroughfare to a people's place - a fabulous oasis and mecca for locals and tourists alike."

The artist is responding to a draft masterplan for the city centre, which has suggested blocking parts of the country's premier retail street to vehicles and turning it into a mall.

A big driver for the masterplan is a report by a Danish urban design team, Gehl Architects, whose founding figure Jan Gehl said Auckland had all the ingredients to be a great city, but needed to address how much space was dedicated to cars and how much to pedestrians.

Auckland Council has started creating several shared spaces in the central city, where pedestrians and vehicles share a road surface, but senior planners and politicians are keen to go further, including banning vehicles from parts of Queen St.

Lett said he had been inspired by the High Line on Manhattan's west side, a 2.3km park built on an abandoned, elevated railway line.

The US$50 million ($63 million) project, which opened two years ago, has become a big attraction and spurred economic development along its path.

The artist wants to recreate the Waihorotiu Stream, which ran from the Karangahape ridge down what is now Queen St and into the sea. It became a waterway, known as the Ligar Canal, but was built over as the city grew.

Lett said the project could be designed by landscape architects, waterflow engineers, artists and gardeners, while other areas could take inspiration from nature.

It would be an ideal site for live music, small concerts and to exhibit outdoor art, he said.

"The spin-off effects could be substantial and new commercial activity would be generated. Cafes, bars, tourist service sites and boutique shopping would start up and flourish," Lett said.

As well as turning part of Queen St into a mall, the masterplan suggests converting Hobson and Nelson Sts into tree-lined, two-way roads; light rail or rapid transit connecting the waterfront, city centre and inner-city suburbs; and building more open spaces and plazas.

Other suggestions to improve the city centre are a new primary school for the residential population of 22,000, the boulevarding of Quay St and a possible Pacific Cultural Centre.

The masterplan is open for public submissions until the end of this month.