A piece of land surrounded by a chain link fence could one day be home to one of the City of Austin's most controversial projects.

"The voters approved water treatment plant number four back in the mid 1980s," Mayor Lee Leffingwell said.

Since then the project has been on again and off again.

"We've kind of made do with other alternatives, but now we're sort of running out of options," Leffingwell said.

Leffingwell is convinced there's only one option left and that is to build the $508 million project on a piece of land near the intersection of R.M. 2222 and F.M. 620, near Lake Travis.

"In effect right now, it's like we're driving around on a spare tire, and I for one will not roll the dice with the health and safety of the people of Austin," Leffingwell said.

Building the plant that take water out of Lake Travis is a gamble many in the environmental community said isn't worth the price tag.

"Once we build it and we've made that debt commitment, then we have to feed the beast. They have no choice but to encourage water waste for the next 30 years," Save Our Springs Executive Director Bill Bunch said.

Bunch, along with several other environmental groups, said the City of Austin's future water use projections are much higher than they should be. They said the city doesn't need to spend the half billion dollars right now to build the project.

"We feel like there's no urgency. We can step back and study our options, and in that interim time, pursue conservation aggressively," Bunch said.

That's an opinion some city council members agree with, but others said keeping the project on track is imperative.

The city council will hear from both sides of the issue Thursday at 6 p.m, during a special called meeting at the Palmer Events Center, 900 Barton Spring Rd.