San Antonio Audubon Society tour guide Georgina Schwartz leads a walking tour as Ozzie Reguera, left, and Rick O’Brien identify a red tail hawk during a beginner’s bird walk at Judson Nature Trails in Alamo Heights in 2017.

San Antonio Audubon Society tour guide Georgina Schwartz leads a beginner’s bird walk at Judson Nature Trails in Alamo Heights in 2017.

Alamo Heights contracted with Vortex Services to replace a section of a sewer main near the Jack Judson Nature Trails from Ogden Lane toward the Olmos Basin. Work begins Monday and should be complete in about five weeks.

A sewer main project is getting underway in Alamo Heights on Monday, and though it won’t affect people’s sewer services or access to roads, those who frequent the Jack Judson Nature Trails won’t have access to some sections over the next few weeks.

The utility work will start mid-block on Ogden Lane between Columbine and Morse streets, and over the next five weeks or so, it will move southwest toward the Olmos Basin, according to a notice sent to nearby residents.

The city contracted with Vortex Services to replace almost half a mile of existing 8-inch and 10-inch sewer line with a new 12-inch sewer main. Pat Sullivan, director of public works, said that tree roots fractured the existing line. Vortex Services will use a technique called “pipe bursting.” That means the existing pipe will be demolished underground and simultaneously replaced with a new sewer pipe. Sullivan said that the technique doesn’t require excavation.

“It has less of an impact on the environment,” Sullivan said.

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The work will be done in sections so that the entire length of the line will not be affected at one time.

The roots have caused challenges along this stretch of sewer line for some time. Sullivan said that for the past three years, the city has been maintaining the line by cutting roots back. He said this section is one of the main lines that feeds out of Alamo Heights and into the San Antonio Water System’s sewage treatment plant.

The work is not expected to close roads or cause any change in people’s sewer service, Sullivan said. But as workers move through the area, there will be times when sections of the Jack Judson Nature Trails will be closed off because there are some parts of the sewer line that run under the trails.

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The city has a maximum $391,825 contract with Vortex Services and has spent $39,900 for Freese and Nichols Engineering to design the project. The project is turning out to be less expensive than the city estimated when putting together its yearly budget. The city originally set aside $535,000 to rehabilitate the sewer main, according to a recent council meeting agenda packet.

Megan Rodriguez covers Alamo Heights, Olmos Park and Terrell Hills for the Express-News.