Austin’s Parks and Recreation Board unanimously endorsed a plan this week to spend hundreds of millions of dollars for improvements at Walter E. Long Metropolitan Park.

The master plan calls for investing more than $800 million to completely transform the 3,700-acre park in East Austin. A few of the dozens of amenities laid out in the plan include a marina, an event lawn, a planetarium and a Ferris wheel.

If approved by the city, the first phase would cover about 300 acres at the southern end of the park. Development during this phase is estimated to cost $144 million, with $26 million from private funders, and includes plans for a rowing course and a “floating water sports zone.”

Finding money is likely to be a challenge. The parks department says it is looking at using bond money, but it will also need private partners with a park this size.

Walter E. Long, which is roughly 10 times the size of Zilker, is the largest park in Austin, but has not received as much attention as other outdoor spaces. Since the area is largely undeveloped, the master plan is meant to be a blueprint for the park’s potential.

City staff spent much of last year collecting public input before putting together the plan. (Originally there was talk about draining Lake Walter E. Long and putting in a privately owned golf course, but that was met with strong opposition.)

Those in favor of the new plan say it would make Walter E. Long a destination park. Critics argue it would turn the area into more of an amusement park than a green space.

Austin City Council members are expected to review the master plan in August when they get back from summer recess.