Ralph Miller of Austintown, Chief of Security for MVSD, stands next to the dam at Meander Creek Reservoir...by R. Michael Semple

MINERAL RIDGE — When the Mahoning Valley Sanitary District begins renovations to its Meander Reservoir Dam in the next couple of years, the dam will better withstand a rare flood event and seismic activity such as earthquakes.

Michael McNinch, chief engineer for MVSD, which provides water for 220,000 area customers, says the $45 million in upgrades includes a measure that will address the increase in earthquakes in the community since 2011 and the possibility of flooding.

A North Side Youngstown injection well was blamed for causing earthquakes in 2011, culminating in a magnitude-4.0 earthquake on Dec. 31, 2011. The injection well was later closed. The Ohio Department of Natural Resources also identifies an injection well on state Route 169 in Weathersfield as the source of two earthquakes — one July 28, 2014, and one Aug. 31, 2014. The July earthquake was a magnitude 1.7, and the August earthquake was 2.1.

McNinch said one primary improvement to the dam will be installation of anchors through the primary spillway into the bedrock.

“This will be done to make sure the spillway does not shift or move as a result of an earthquake” or a significant flood, McNinch said.

He and other MVSD officials have been following the legal and administrative activities associated with the American Water Management injection well in Weathersfield, which is regulated by ODNR, McNinch said. He said the reason is that it “could have a seismic effect on the dam.”

American Water Management and ODNR are debating what type of rules the American Water Management well should follow to prevent the injection well from causing earthquakes that could damage the community, including the Meander Reservoir dam.

A recent ODNR filing in a case before the Ohio Oil and Gas Commssion states the Meander dam is “just three miles away” from the Weathersfield well, and the dam is a “special risk,” as it “serves as the sole drinking water source for over 220,000 people and holds approximately 11 billion gallons of water.”

The filing adds that a study carried out by the engineering firm Gannett Fleming noted that the dam was “not designed using modern standards to withstand earthquakes.” Furthermore, “detailed engineering studies by Gannett Fleming indicated that the dam’s existing upstream slope does not meet current safety criteria for the maximum credible earthquake loadings.”

It says that a “a major earthquake could have catastrophic consequences” because it is “upstream from homes, businesss and industrial sites that would be catastrophically flooded in the event of its breach.”

The filing quotes Weathersfield fire Chief Tom Lambert as saying such a flood would “totally flood out the south side of Niles, downtown Niles and keep heading toward the city of Warren.” Lambert said, “There would be a lot of lives involved.”

The Meander Reservoir dam is 50 feet high and 3,550 feet long with a 260-foot primary spillway located just southwest of the state Route 46 and Salt Springs Road intersection in Mineral Ridge.

Former MVSD president Matt Blair expressed concerns over the safety of the dam in 2017, wondering whether injection-well-induced seismic activity in Youngstown and Weathersfield were contributing to cracks in MVSD buildings and the dam.

HOLLOWAY

However, Tom Holloway, operator of record at the Meander Water Treatment Plant and former MVSD chief engineer, said last week the Gannett Fleming study indicated that seismic activity had not caused any significant damage to the MVSD facilities, including the dam.

“There are no serious cracks in the dam. There are age cracks and things of that nature and the same thing with buildings. We looked close at the dam and the buildings … but there was no significant damage from the one seismic activity we had here,” Holloway said.

Holloway was referring to the magnitude-4.0 Dec. 31, 2011, earthquake caused by a D&L Energy injection well on Ohio Works Drive in Youngstown. But he clarified that he was also referring to the two lesser earthquakes that occurred near an American Water Management Services injection well on state Route 169 in Weathersfield.

“Most of cracks here on the buildings is over time, age and some settlement of the buildings. There was no significant findings that there is a serious crack or issue with the dam,” Holloway said.

Blair and the rest of the MVSD board were in the planning stages for the dam renovation in 2017.

“Our dam wasn’t built for earthquakes,” Blair said in 2017. “When we build out there, if the ground is becoming more unstable, we have to build in a different way like California so we don’t have cracking. It’s kind of a new problem for us.”

FLOODING

Apart from earthquake issues are ones associed with flooding.

A key concept is the “probable maximum flood,” McNinch said, explaining that the probable maximum flood for this area is 19 inches of rain in a 24-hour period, which would be rare.

The Ohio Department of Natural Resources defines a probable maximum precipitation event as “the greatest depth (amount) of precipitation for a given storm duration, that is theoretically possible for a particular area and geographic location” and the probable maximum flood event as “the flood that may be expected from the most severe combination of critical meteorological and hydrologic conditions that are reasonably possible in a particular drainage area.”

The Vindicator reported last November that according to the National Weather Service, the record amount of rainfall the Youngstown area received in one day, since 1931, was 4.65 inches on July 21, 2003. In the last 10 years, the most rain the area received in a one-day period was 3.96 inches on July 10, 2013.

Engineers working on behalf of the MVSD determined that if the reservoir got 19 inches of rain in a 24-hour period, “there was the potential” that the dam might “over top” or that “parts of our spillways would shift,” McNinch said.

At that point, it is possible the dam could “breach,” meaning water might create an opening or “breakthrough,” allowing water to go downstream and endanger people.

“The probability of it is extremely low, but the consequences are extremely high,” McNinch said of a breach of the dam. “There is no immediate threat of a dam failure. What we are trying to do is future proof. We’re trying to update the dam to be able to sustain a potential probable maximum flood,” he said.

“The dam was built with 1920s technology, and it came online in 1931, so it’s approaching 100 years old. So just like any other major structure, you need to do preventative maintenance, and that is what we are looking at,” McNinch said.

Holloway and McNinch have said one upgrade to the dam will be raising the curb on the dam because at the height it is now, it “could wash out and fail,” Holloway said.

“Part of the project is to make sure that the curb is the same elevation / height across the entire width of the dam,” McNinch said. If there was a probable maximum flood, it is possible that water “could bypass the primary and auxiliary spillway, which could cut into the earthen part of the dam and then into the concrete core wall leading to a dam failure,” McNinch said. The concrete core wall is inside of the earthen portion of the dam, McNinch said.

The dam rehabilitaton also will construct a new auxiliary spillway, flatten downstream embankments, upgrade dam-related instrumentation, electric service and lighting and replace east and west dam access roads.

ENVIRONMENTAL STUDY

In mid-May, the MVSD ran a legal ad asking for companies to bid by June 7 on a contract to perform an environmental assessment regarding the renovation. The cost is estimated at $100,000.

McNinch said the Ohio Emergency Management Agency recommended that the MVSD perform the assessment to improve the district’s chances of being approved for $30 million in grant money it is seeking from the Federal Emergency Management Agency to pay for the $45 million in dam renovations.

The assessment “basically researches all of the impacts — environmental, ecological, any potential flooding — that could occur while the construction is under way,” McNinch said. It would also assess any potential historical implications.

The MVSD hopes to have the environmental assessment complete by this fall and will apply by Jan. 1, 2023, for the $30 million grant.

The engineering for the renovations is complete and some of the funding — about $12 million — has been set side for the renovation, McNinch said. “We received almost all of our permits from the state and federal level. We’re working closely with ODNR (on a construction permit) and are expecting that permit to be finalized in the next couple of weeks. We are that far along,” McNinch said.

2023

“We are planning for going out for construction bids in the fall of 2023 because the primary driving factor is safety, but the other key issue is inflation,” McNinch said. “It is a $45.456 million project as of January of this year, but it’s about 8 percent annual inflation, so if we wait another year, the full project has gone up $3.2 million,” he said.

He expects the renovation to go forward next year with or without the $30 million grant.

If the grant is not awarded, “We have a mechanism to go forward in a worst-case scenario to pay for it in-house through our rate structure,” McNinch said. By that, he means that ongoing revenue for the nonprofit MVSD would be used to pay for the renovations.

If the federal grant application is successful, the MVSD will add $15 million in matching funds to the $30 million grant. The district’s ongoing revenues would be used for other, ongoing MVSD improvements.

“We are always upgrading, improving, making sure that we are in the best possible position to serve everybody in the entire region,” he said.

“We’re trying to keep our costs as low as possible by getting any grant money that is out there,” McNinch said. “We have gotten tremendous support regionwide. I’m talking about township trustees at every level, local mayors all the way up to the federal level and Congressman Johnson and Congressman Tim Ryan.”

U.S. Rep Bill Johnson, a Republican of Marietta, toured the MVSD facilities in November to learn more about it and the renovation. Johnson’s 6th Congressional District will include all of Trumbull and Mahoning counties starting with this year’s election. It will also include Columbiana, Jefferson, Carroll, Harrison, Belmont, Noble and Monroe counties and all but four townships in Washington County.

The Meandor Resevoir provides drinking water to about 220,000 people in Mahoning and Trumbull counties.

Johnson expressed support for the renovation project.

“This is real infrastructure,” Johnson said. “We’ll certainly fight for it, you don’t need to sell me on the need for it because this is not unlike the water systems or sewer systems throughout Appalachia or throughout my region of the state.”

erunyan@vindy.com