July 26 torrential downpour, Cantrell Dam’s malfunction (Part 2)

by Kathleen Sloan | October 22, 2020
10 min read
Overlooked: Cantrell Dam, unknown to most Sierra Countians, is the long, sandy-colored earthwork pictured here between the two scrub-covered hills at the right and left of the image. Inadequate maintenance of the dam contributed to extensive flooding downstream during the midsummer deluge. Photograph by Ron Fenn

This summer Truth or Consequences experienced two major disasters within 40 days—a fire and then a flood—which tested and revealed the area’s level of hazard preparedness.

Our two-part series, “Fire and then Flood Show Prevention Could Have Mitigated Extent of Damage,” examines the circumstances surrounding these emergencies and assesses lessons learned. The first story in the series, published last Friday, covered the Mims Lake fire that began June 17 and ended June 20. Part 2 of the series offers a similar evaluation of the July 26 rain event and the infrastructure malfunction that contributed to extensive flooding in the S. Broadway area. 

COSTLY LACK OF MAINTENANCE

Cantrell Dam wasn’t on anyone’s radar until the July 26 deluge gave it importance. The partial breach of the dam, located on Bureau of Land Management property north of Interstate 25 about 1.5 miles north of the Williamsburg exit, contributed to extensive flooding downstream in Williamsburg and western Truth or Consequences.

Maintenance of the dam—for which the City of Truth or Consequences has tacitly accepted responsibility—was inadequate. Erosion and sedimentation contributed to the dam’s overtopping at its eastern and western ends, which released storm waters directly toward the two communities it was built to protect.

arroyo that channeled storm water toward Williamsburg
The partial breaching of the dam channeled storm water into a culvert under I-25 (whose termination point is visible in the lower right of the image) and into an arroyo leading toward Williamsburg. Photograph by Ron Fenn

T or C is seeking natural-disaster relief for flood damages to its facilities estimated by City Manager Morris Madrid at “less than $750,000” at a Sept. 9 commission meeting. Madrid also sought permission to apply for a $750,000 grant from the New Mexico Finance Authority to repair Cantrell Dam at the Sept. 23 commission meeting.

STATE INSPECTION CONFIRMS DAM’S BREACH

It is impossible to accurately quantify how much rain fell over a very short time on July 26. The National Weather Service, which uses measurements from the Truth or Consequences Airport, sent out a flood warning that up to 2.5 inches had fallen by 5:30 p.m.

But Williamsburg, about 10 miles south, was hit much harder.

KOB 4 and other news outlets said up to 5 inches fell within an hour around Williamsburg, relying on verbal reports from eyewitnesses.

This reporter lives in Williamsburg and can attest this estimate is fairly accurate. But how much of the rising water was from localized rain and how much was from water normally held back by Cantrell Dam cannot be separated out and measured. 

Sierra County Emergency Manager Paul Tooley, in an interview with Ryan Laughlin at KOB 4 on July 27, said, “We found a small dam up in that area that actually got breached. It got deep enough there—about 20 feet, and was pouring water all the way down Hyde Street. All the way into the ball fields down towards the river.”

Several homes were damaged, but no one was hurt, according to Tooley.

His statements were refuted by Madrid and Mayor Sandra Whitehead at the Aug. 12 city commission meeting. “The dam didn’t breach,” they insisted.

Given Madrid’s and Whitehead’s statements, Tooley, understandably, did not want to be interviewed for this article.  

Besides working for the county as the emergency manager, Tooley is also T or C’s fire chief. His professional assessment that the Mims Lake fire could have been prevented was similarly refuted by Madrid at the June 24 city commission meeting.

However, Tooley’s assessment that the Cantrell Dam’s malfunction was a prime cause of the subsequent flood damage was affirmed by the Office of the State Engineer’s Dam Safety Bureau.

CAUSES OF THE BREACH

Dam Safety Bureau Chief Charles Thompson sent an engineer, James Head, to examine four “jurisdictional” and two “non-jurisdictional” dams in Truth or Consequences on July 30. Most of Thompson’s 11-page report was taken up with Cantrell Dam.

Thompson’s report is dated Aug. 14. He addressed it to Madrid and Williamsburg Mayor Deborah Stubblefield and sent copies to the state Disaster Recovery Manager Rosalita Whitehair, among other state and federal officials.

Describing Cantrell Dam as a “non-jurisdictional floor retardation dam,” Thompson wrote: “This structure experienced a very substantial uncontrolled flood release that resulted in the flooding of downstream residential areas located within the town limits of Williamsburg, New Mexico.”

Cantrell Dam is not inspected and overseen by the Dam Safety Bureau, because it is too small to fall under their jurisdiction. But the Dam Safety Bureau does have the authority to make the responsible entity fix “dangerous works,” which Thompson made clear in the report.

Non-jurisdictional dams are less than 25 feet high and hold back less than 15 acre feet of water. If a dam’s height is six feet or lower, it must hold back more than 50 acre feet of water to be considered jurisdictional by the OSE.  

Thompson’s report estimates the Cantrell Dam is about 20 feet high, 310 feet long and its flood detention pond holds less than 15 acre feet of water. 

Because Cantrell Dam is non-jurisdictional, there is little documentation on it. Thompson’s report said local sources think it was built “under the supervision of the Natural Resources Conservation Service.”

It shows up on United States Geological Survey maps in the early 1960s, Thompson wrote.

Tooley said the county queried the Bureau of Land Management, since the Cantrell Dam is on BLM land, but it, too, had no documents.

The Sierra County Sun submitted a public-records request to the City of Truth or Consequences, asking for any documents revealing what agency built the dam, what it was designed to do and how it was handed over to the city, but “no such documents exist” was the response.

Unable to rely on government documents for the dam’s design or holding capacity, Thompson looked at Google Earth maps to compare the dam’s post- and pre-flood condition.

Google Earth aerial view of Cantrell Dam
Erosion contributed to Cantrell Dam’s malfunction. The Sun examined two decades of Google Earth maps of the dam site, the latest available version of which is this 2015 aerial view. The maps show the increasing presence over time of trails and loops around the dam site, vehicular use possibly contributing to erosion. The main access road at the dam’s east end permits travel up and over the dam and down the combination road/spillway. Photograph (amended with location indicators) courtesy of Google Earth

The “original storage capacity, (currently unknown), is significantly reduced due to sediment accumulation,” Thompson discovered.

In addition to the storage capacity being diminished, Thompson noted erosion problems that contributed to the dam’s malfunction on July 26.

sedimentation and vegetation in the flood detention pond
Sedimentation and vegetation of the shallow flood detention pond at the dam’s rear limited water retention on July 26. Photograph by Ron Fenn

The greatest erosion was at the “right downstream groin,” Thompson said, which would be the left side of the dam, viewing it from I-25.

To the far-right side of the dam, Thompson said, is a combination access road and spillway, which showed “severe” erosion in 2015 Google Earth maps.  

As a result of the erosion on the left and right sides of the dam, as well as the sedimentation limiting water retention, water not only went over the right-side spillway, it also overtopped the left side of the dam, Thompson said.

T OR C’S “TIMELY” REHABILITATION OF DAM STRONGLY RECOMMENDED

The dam’s “partial breach,” Thompson said, in a Sept. 29 interview, caused considerable damage to the I-25 culvert that runs underneath the highway about 200 yards away. In his report he warned the New Mexico Department of Transportation should be notified.

Severe erosion in a third spot on the Cantrell Dam also concerned Thompson. On the left side, near the bottom (when looking from I-25) are two “corrugated metal pipe outlet conduits,” he said. The “headcuts” caused by water streaming from the pipes are visible in the 2015 Google maps. 

The erosion under the outlet pipes “will eventually result in total failure of the dam if timely rehabilitation efforts to control additional erosion are not taken,” Thompson said.

outlet pipes causing erosion at dam's western end
Water outlet pipes near the foot of the dam’s face are causing erosion that the post-flood inspection report said will eventually result, if unaddressed, in the dam’s “total failure.” Photograph by Ron Fenn

Thompson said he didn’t know if Truth or Consequences or Williamsburg was responsible for maintaining the dam, but “recommended that the owner of Cantrell Dam make the necessary timely repairs and perform due diligence with regard to maintaining the dam and the associated appurtenances (spillway and outlet works) to ensure that the structure performs properly.”

The City of Truth or Consequences is responsible for maintaining Cantrell Dam.

Madrid, at the Aug. 12 city commission meeting, didn’t explain or provide documents demonstrating city responsibility, but treated it as a given by including Cantrell Dam among 15 other sites for which the city is seeking disaster-relief funding.

The city commission held an emergency meeting July 29 to declare a disaster, a prerequisite for requesting state and federal funding.

Madrid hired the city’s on-call engineering firm, Wilson & Company of Las Cruces, to do the city’s assessment of flood damage. Funding will only be provided for “new damage,” he said, that is, damage caused by the flood, not pre-existing damage caused by neglect of structures. Therefore, it is essential the city demonstrate it adequately maintained Cantrell Dam.

Wilson & Company, during its Aug. 12 presentation to the city commission, claimed repeatedly the city had good maintenance records for various structures. However, maintenance records requested and received by the Sierra County Sun for Cantrell Dam were scant and prove nothing.

The city provided an unnamed person’s hand-written notes, dated “June/19,” the 19 possibly referring to the day or the year. The notes are headed, “Mud Mountain Dam Project,” which is the wrong dam.

The Sun’s request to see maintenance records for Cantrell Dam produced (among other inconclusive documents) these handwritten notes of backhoe work at “Mud Mtn Dam Project.”

Pictures of Cantrell Dam were also among the Inspection of Public Records Act documents supplied to the Sun as maintenance records. They are undated, but two have hand-written notes on top of the image referring to the flood damage. Post-flood pictures are not proof of prior maintenance.

There is no way to know if the other photos pre-date the flood, as they lack dates and the names of their authors.

The Sierra County Hazard Mitigation Plan, which the city adopted, along with Sierra County, Elephant Butte and Williamsburg, in 2018, will not help the city demonstrate it maintained Cantrell Dam.

Adopting a Hazard Mitigation Plan is another prerequisite for receiving Federal Emergency Management Agency or state emergency management funding after a flood or disaster.

The 2018 plan names and plans for disasters resulting from failure of only the Elephant Butte and Caballo dams.

During the Sept. 9 city commission meeting, Madrid said Wilson & Company’s assessment of damage was “under $750,000,” and therefore federal disaster-relief funding “was unlikely.”

At the following city commission meeting on Sept. 23, Madrid appeared to reverse himself on what happened at Cantrell Dam. After denying Tooley’s assessment the dam breached, Madrid asked the city commission’s permission to submit a completed $750,000 grant application to the New Mexico Finance Authority for the dam’s “design and rehabilitation.” The dam needed to be fixed, he said, “to provide flood protection for the west side of the city.”

The city commission approved the grant application with no comment or questions.

The Sun asked each city commissioner to comment on the city’s switch from denying the dam had malfunctioned to supporting a $750,000 fix for the Cantrell Dam. No commissioner responded.

In a Sept. 29 interview, Thompson said he had not heard from the city about his report. When the Sun told him of the grant application to fix the dam, he was pleased. “It’s a good outcome.”

author
Kathleen Sloan is the Sun’s founder and chief reporter. She can be reached at kathleen.sloan@gmail.com or 575-297-4146.
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Understanding New Mexico's proposed new social studies standards for K-12 students

“The primary purpose of social studies is to help young people develop the ability to make informed and reasoned decisions for the public good as citizens of a culturally diverse, democratic society in an interdependent world.”
—National Council for the Social Studies 

Reader Michael L. Hayes of Las Cruces commented: What impresses me is that both the proposed standards and some of the criticisms of them are equally grotesque. I make this bold statement on the basis of my experience as a peripatetic high school and college English teacher for 45 years in many states with many students differing in race, religion, gender and socioeconomic background, and as a civic activist (PTA) in public education (My career, however, was as an independent consultant mainly in defense, energy and the environment.)

The proposed social studies standards are conceptually and instructionally flawed. For starters, a “performance standard” is not a standard at all; it is a task. Asking someone to explain something is not unlike asking someone to water the lawn. Nothing measures the performance, but without a measure, there is no standard. The teacher’s subjective judgment will be all that matters, and almost anything will count as satisfying a “performance standard,” even just trying. Students will be left to wonder “what is on the teacher’s mind?” or “have I sucked up enough.”

Four other quick criticisms of the performance standards. One, they are nearly unintelligible because they are written in jargon. PED’s use of jargon in a document intended for the public is worrisome. Bureaucrats often use jargon to confuse or conceal something uninformed, wrong or unworthy. As a result, most parents, some school board members and more than a few teachers do not understand them.

Two, the performance standards are so vague that they fail to define the education which teachers are supposed to teach, students are supposed to learn, and parents are supposed to understand. PED does not define words like “explain” or “describe” so that teachers can apply “standards” consistently and fairly. The standards do not indicate what teachers are supposed to know in order to teach or specify what students are supposed to learn. Supervisors cannot know whether teachers are teaching social studies well or poorly. The standards are so vague that the public, especially parents or guardians, cannot know the content of public education.

Three, many performance standards are simply unrealistic, especially at grade level. Under “Ethnic, Cultural and Identity Performance Standards”; then under “Diversity and Identity”; then under “Kindergarten,” one such standard is: “Identify how their family does things both the same as and different from how other people do things.” Do six-year-olds know how other people do things? Do they know whether these things are relevant to diversity and identity? Or another standard: “Describe their family history, culture, and past to current contributions of people in their main identity groups.” (A proficient writer would have hyphenated the compound adjective to avoid confusing the reader.) Do six-year-olds know so much about these things in relation to their “identity group”? Since teachers obviously do not teach them about these other people and have not taught them about these groups, why are these and similar items in the curriculum; or do teachers assign them to go home and collect this information?

Point four follows from “three”; some information relevant to some performance measures requires a disclosure of personal or family matters. The younger the students, the easier it is for teachers to invade their privacy and not only their privacy, but also the privacy of their parents or guardians, or neighbors, who may never be aware of these disclosures or not become aware of them until afterward. PED has no right to design a curriculum which requires teachers to ask students for information about themselves, parents or guardians, or neighbors, or puts teachers on the spot if the disclosures reveal criminal conduct. (Bill says Jeff’s father plays games in bed with his daughter. Lila says Angelo’s mother gives herself shots in the arm.) Since teacher-student communications have no legal protection to ensure privacy, those disclosures may become public accidentally or deliberately. The effect of these proposal standards is to turn New Mexico schools and teachers into investigative agents of the state and students into little informants or spies.

This PED proposal for social studies standards is a travesty of education despite its appeals to purportedly enlightened principles. It constitutes a clear and present danger to individual liberty and civil liberties. It should be repudiated; its development, investigated; its PED perpetrators, dismissed. No state curriculum should encourage or require the disclosure of private personal information.

I am equally outraged by the comments of some of T or C’s school board members: Christine LaFont and Julianne Stroup, two white Christian women, who belong to one of the larger minorities in America and assume white and Christian privileges. In different terms but for essentially the same reason, both oppose an education which includes lessons about historical events and trends, and social movements and developments, of other minorities. They object to the proposal for the new social studies standards because of its emphasis on individual and group identities not white or Christian. I am not going to reply with specific objections; they are too numerous and too pointed.

Ms. LaFont urges: “It’s better to address what’s similar with all Americans. It’s not good to differentiate.” Ms. Stroup adds: “Our country is not a racist country. We have to teach to respect each other. We have civil rights laws that protect everyone from discrimination. We need to teach civics, love and respect. We need to teach how to be color blind.”

Their desires for unity and homogeneity, and for mutual respect, are a contradiction and an impossibility. Aside from a shared citizenship, which implies acceptance of the Constitution, the rule of law and equality under the law, little else defines Americans. We are additionally defined by our race, religion, national origin, etc. So mutual respect requires individuals to respect others different from themselves. Disrespect desires blacks, Jews or Palestinians to assimilate or to suppress or conceal racial, religious or national origin aspects of their identity. The only people who want erasure of nonwhite, non-Christian, non-American origin aspects of identity are bigots. Ms. LaFont and Ms. Stroud want standards which, by stressing similarities and eliding differences, desire the erasure of such aspects. What they want will result in a social studies curriculum that enables white, Christian, native-born children to grow up to be bigots and all others to be their victims. This would be the academic equivalent of ethnic cleansing.

H.E.L.P.

This postmortem of a case involving a 75-year-old women who went missing from her home in Hillsboro last September sheds light on the bounds of law enforcement’s capacity to respond, especially in large rural jurisdictions such as Sierra County, and underscores the critical role the public, as well as concerned family and friends, can play in assisting a missing person’s search.

Reader Jane Debrott of Hillsboro commented: Thank you for your article on the tragic loss of Betsey. I am a resident of Hillsboro, a friend of Rick and Betsey, and a member of H.E.L.P. The thing that most distresses me now, is the emphasis on Rick’s mis-naming of the color of their car. I fear that this fact will cause Rick to feel that if he had only gotten the facts right, Betsey may have been rescued before it was too late. The incident was a series of unavoidable events, out of everyone’s control, and we will never know what place the correct color of her car may have had in the outcome. It breaks my heart to think that Rick has had one more thing added to his “what ifs” concerning this incident.

Diana Tittle responded: Dear Jane, the Sun undertook this investigation at the request of a Hillsboro resident concerned about the town’s inability to mount a prompt, coordinated response to the disappearance of a neighbor. From the beginning, I shared your concern about how our findings might affect Betsy’s family and friends. After I completed my research and began writing, I weighed each detail I eventually chose to include against my desire to cause no pain and the public’s right to know about the strengths and limitations of law enforcement’s response and the public’s need to know about how to be of meaningful assistance.

There was information I withheld about the state police investigation and the recovery. But I decided to include the issue of the car’s color because the individuals who spotted Betsy’s car emphasized how its color had been key to their identification of it as the vehicle described in Betsy’s Silver Alert. Because the misinformation was corrected within a couple of hours, I also included in this story the following editorial comment meant to put the error in perspective: “The fact that law enforcement throughout the state was on the lookout in the crucial early hours after Betsy’s disappearance for an elderly woman driving a “light blue” instead of a “silver” Accord would, in retrospect, likely not have changed the outcome of the search” [emphasis added].

I would also point to the story’s overarching conclusion about the inadvisability of assigning blame for what happened: “In this case, a perfect storm of unfortunate circumstances, many of them beyond human control, hindered the search that it would fall to Hamilton’s department to lead.”

It is my hope that any pain caused by my reporting will eventually be outweighed by its contribution to a better community understanding of what it will take in the future to mount a successful missing person’s search in rural Sierra County.


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Fire and then flood show prevention could have mitigated extent of damage (Part 1)
by Kathleen Sloan | October 16, 2020

This summer Truth or Consequences experienced two major disasters within 40 days—a fire and then a flood—which tested and revealed the area’s level of hazard...


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