EDITOR’S NOTE: After News-Bulletin deadline, the New Mexico Department of Transportation provided an update on repairs to the culvert where the erosion and collapse occurred in May.
Kimberly Gallegos, the New Mexico Department of Transportation District 3 public information officer, said the existing 54-inch corrugated metal culvert that runs under N.M. 6 — Main Street — on the east side of the Los Lunas river bridge will be replaced with a 72-inch diameter reinforced concrete pipe.
“The cause of the failure was not determined, only that the pipe had failed and not structurally sound for repair without replacement,” Gallegos said. “The repair will be complete replacement, to provide service life and capacity for the foreseeable future.”
On Saturday, May 13, around 10 p.m., a sinkhole formed due to erosion around the culvert which caused a section of sidewalk and dirt shoulder on the north side of the street to collapse.
The collapse occurred where the Lower Peralta Drain culvert passes under the street east of the Rio Grande. Water in the drain had been extremely high due to unusually high flows in the Rio Grande.
Replacement of the culvert is expected to be completed by late fall of this year, Gallegos said.
The project will cost about $3.3 million, which NMDOT will fund on its own, and the village will be responsible for any repair costs to the water and sewer lines that run under the bridge, she said.
Shortly after the sidewalk collapsed, village of Los Lunas water department personnel made the decision to shut off the 16-inch water line running under the bridge, said Michael Jaramillo, public works director for the village.
The water line wasn’t damaged, but was shut off to prevent more issues, Jaramillo said, noting it if had broken the erosion would have become much worse.
Last year, the village completed its north waterline loop and was able to bring it online to provide water to residents and businesses east of the bridge while the line under the bridge is off. Water delivery has been going through the north loop since May.
LOS LUNAS — There’s still no official word on when repairs to the culvert and collapsed sidewalk east of the Los Lunas river bridge will be completed or what exactly needs to be done to restore the westbound lanes of N.M. 6 to full usability.
Late on the evening of Saturday, May 13, after weeks of high water in the Lower Peralta Drain, which passes under the highway east of the Rio Grande, erosion caused a section of the sidewalk to collapse, sending Los Lunas resident Sergio Marquez, 40, plunging into the fast-moving water.
He was rescued thanks to the efforts of passers-by and his son, who was with him on their regular bike ride.
Kimberly Gallegos, the New Mexico Department of Transportation District 3 public information officer, said DOT was working with other agencies to “develop alternatives that will be acceptable moving forward with repairs. Alternatives, such as sliplining or full repairs, are being looked into.”
Sliplining, which has been used since the 1940s, is a technique for repairing leaks or restoring structural stability to an existing pipeline. It involves installing a smaller, “carrier pipe” into a larger “host pipe”, grouting the space between the two pipes, and sealing the ends.
Julia M. Dendinger | News-Bulletin photo
Large pumps pull water out of the Lower Peralta Drain to dewater the area that collapsed under a sidewalk on the east side of the Los Lunas river bridge.
“Both options would have very different time lines for completion,” Gallegos said, adding once a decision was made she would let the News-Bulletin know which route repairs would take.
The drain has been dewatered, with a steel dam holding water back from the eroded area while large pumps moved the captured water over the levee and back into the bosque, which is already flooded due to high flows in the Rio Grande.
“Since the area was just dewatered, crews were able to place a camera through (the culvert,)” Gallegos said. “However, it is still premature to know what happened until we can run modeling for alternatives. Currently, there is no new information to share other than we are continuing to monitor the situation. Crews are taking time to analyze the area to provide data driven answers for the public and local community.”
In May, a sinkhole formed due to erosion at the culvert under Main Street — aka N.M. 6, a state highway — where the Lower Peralta Drain passes under the street east of the Rio Grande.
This caused a section of sidewalk and dirt shoulder on the north side of the street to collapse.
High flows of the Rio Grande have pushed large volumes of water into the Lower Peralta Riverside Drain east of the river, which is its purpose. The drains serve as a catchment for river water during high-flow years, and help prevent water from flooding further into the valley. The seepage is carried south to beyond the city of Belen.
While the riverside drain is part of the Middle Rio Grande Conservancy District’s infrastructure, district CEO and chief engineer Jason Casuga said the culverts under the roadway have been NMDOT’s to maintain since 1989, when the highway was widened to four lanes.
Julia M. Dendinger began working at the VCNB in 2006. She covers Valencia County government, Belen Consolidated Schools and the village of Bosque Farms. She is a member of the Society of Professional Journalists Rio Grande chapter’s board of directors.
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April 25, 2024
