Part 1: Mohawk Dam in need of repair
The Mohawk Dam, a Coshocton County/ Walhonding River landmark that is slowly but surely deteriorating. Rehabilitation will cost nearly $200 million, and the U.S. Army Corps of Engineers says the need is urgent.
NELLIE — On sunny days, dams are appreciated more for the recreational reservoirs they create than as intricate flood control systems. Still, there are times manmade structures are needed to contain more than enough water to turn Main Streets into shipping lanes. That’s when dams look, in polite conversation, darn good.
Situated on the Walhonding River, below the confluence of the Kokosing and Mohican rivers in Coshocton County, Mohawk Dam is a case in point. It stands sentinel over the Walhonding Valley, and since 1937 thousands have entrusted their homes and personal safety to its care. The old gal’s not what she used to be, but for 78 years she’s always been enough.
Numerous New Deal-era dams exist because Ohio’s Great Flood of 1913 created a healthy fear of an angry Neptune. Flooding pressed Mohawk Dam into service in 1937 before construction was even complete, and it made an excellent first impression. Author Nancy Lowe Lonsinger would later report that below the dam in Nellie and Warsaw, and onward toward Coshocton, “there were only a few puddles. Folks downstream were sure the dam was worth every cent spent on it.”
Coshocton sustained damage, but that was blamed on an unchecked Killbuck Creek, which enters the Walhonding below Warsaw. Without Mohawk Dam, flooding of the county seat would have been much worse.
At 2,300-feet wide, 111-feet tall and 35-feet thick, Mohawk incorporates a staggering 2.6 million cubic yards of soil, rock fill and concrete. Untrained eyes behold what appears to be an impenetrable monolith, but in truth Mohawk is far beyond its forecast service life. Unseen are destabilizing sedimentation and erosion, products of water’s perpetual obedience to gravity.
The U.S. Army Corps of Engineers (USACE) manages Mohawk Dam (and 15 others in the Muskingum Watershed Conservation District), and warns that without repairs it will eventually fail. Mohawk was downgraded to USACE Action Class Two in 2007, and is rated “unsafe or potentially unsafe.”
Recent developments at Buckeye Lake may create an impression that compromised dams are repaired at the speed of water over a falls, but the real-world flow is more like molasses. Restoring dams to meet USACE’s 3Rs — Redundancy, Resiliency and Robustness — takes time. Eight years after its downgrade, a final repair plan is still a year away. The start of work could be years off, and will likely span a decade.
USACE projects are subjected to numerous technical, safety-assurance and peer reviews, and Mohawk’s Project Delivery Team includes 100-plus experts from 18 specialties. Rehab will be timeconsuming process, but USACE foresees no unusual challenges.
Shallow water and boating restrictions are hurting Buckeye Lake businesses, but Mohawk is a “dry” dam designed solely for flood control. The Walhonding normally flows through the spillway unimpeded, but from time to time flexes its muscles and tests Mohawk’s strength. Most notably, the aged dam had to contain an 80-foot wall of water that accumulated in 2005. Undeveloped areas upstream flooded in order to spare populated areas downstream, and the dam held.
The final report on Mohawk’s rehab is expected next October. The lion’s share of the $180-200 million project will be paid with federal dollars, and a yet undetermined “local share” of between 3 and 27 percent by MWCD. Funding will be subject to the vagaries of Congressional appropriations.
Meanwhile, Nellie, Warsaw and Coshocton will keep a watchful eye out, plan for the worst, and hope for the best.
Bill Amick/Mount Vernon News
Mohawk Dam serves as flood control along the Walhonding River, just south of where the Kokosing and Mohican rivers converge. The 78-year-old earthen structure is in need of repair.
Part 2: Mohawk Dam impacts several counties
NELLIE — Sleepy Nellie, the village of Warsaw, and Coshocton are home to a third of Coshocton County’s 36,000-plus residents, and the Walhonding River reaches them in that order after passing through Mohawk Dam. Other than a handful of folks pushing 90, locals have no recollection of life before the huge pile of rocks they know as Ohio 715, the straightest crooked line from Nellie to Walhonding. Those rocks shield deceptively complex flood abatement mechanisms that have “always” been there, and it’s understandable if residents take Mohawk Dam for granted. But based on U.S. Army Corps of Engineers (USACE) assessments, they might want to sleep with one eye open and an ear on the radio whenever the Kokosing and Mohican rivers feed the Walhonding at flood stage.
The Great Ohio Flood of 1913 and subsequent events damaged population centers and developed riverside parcels, but since 1937 Walhonding floods have been tamed by the massive earthen dam in west-central Coshocton County. Mohawk was designed for floods more severe than 1913’s epic event, and is modified to retain water to a depth of 115 feet.
Its sternest test came in 2005 from a perfect storm of rain and winter melt. The 80plus feet of water that backed up were contained, but sedimentation and erosion of permeable materials beneath the dam have weakened it. Accordingly, Mohawk was downgraded to USACE Safety Action Class II in 2007, which by definition deems it “unsafe or potentially unsafe” with “urgent” need of repair.
Brian McClain is USACE Project Administrator at Mohawk Dam, and arguably has more hands-on knowledge of it than anyone. He recently explained that as a “dry” dam Mohawk is essentially scenery when the Walhonding plays nice. When its Kokosing and Mohican tributaries rise above their banks, however, capture and release of water at Mohawk impacts not only Coshocton County but upstream counties including Knox and the Muskingum Watershed’s 147mile run downstream to the Ohio River. At full capacity, Mohawk’s reservoir would make 17 Knox Lakes and release up to 7,000 cubic feet of water per second.
But is it safe?
“I live and work beneath the dam and sleep just fine,” McClain said. “Does is leak? All dams leak. Does it have issues? Yes, it does. Some we’ve minimized, some will be part of a major rehab project, and some we don’t yet completely understand. Using GPS technology and 3D cameras, a study is being made on movement at the dam. When you’re here every day you can’t detect small changes, but photos taken several years apart tell us a lot.
“Is the dam safe? Yes, absolutely.”
USACE readiness protocols include communication and evacuation plans, meetings with involved agencies, economic impact statistics, inundation reports, and estimates of life and property losses expected from “events” up to and including catastrophic failure.
Knox County’s passive role is to provide 12.4 square miles of normally dry land to store waters backed-up from Mohawk. Rob McMasters is the Coshocton County counterpart to Knox County EMA Director Mark Maxwell, and while Mohawk Dam is a secondary concern of Maxwell’s, it’s front and center for McMasters.
“They (USACE) have plans in place that include inundation maps, and of course we have flood plans,” McMasters said. “I depend on what they tell us. They know how the dam performs and what to expect. When there are questions, I can always rely on Brian.”
Mohawk looks much the same as it did in 1937, but updates above and below ground level have stretched its 50-year design to 78. It will likely be 90 when its rehab is completed. Virtually all who remember its construction will have passed, but Mohawk is expected to preside over memories of new generations for decades to come.
Part 3: Mohawk Dam quietly controls water
WARSAW — As what figures to be the costliest infrastructure project in the history of Coshocton County approaches, the buzz is muted. Perhaps that’s because rehabilitation of Mohawk Dam is needed in the interest of safety, and safety lacks sex appeal. Maybe it’s because only a thin slice of costs approaching $200 million will be generated locally, with any financial sting spread across the 18-county Muskingum Watershed Conservation District. It could be that awareness won’t peak until the landscape sprouts orange detour signs. Mohawk Dam is far past its prime, yet inspires little water-cooler gossip.
Perhaps the U.S. Army Corps of Engineers, like FEMA before Katrina, is popular and trusted. With 12,000 dams in the country, many of which are USACE products, the biggest dam problem of late is lack of water in drought-stricken states. There’s no public expectation for USACE to create rain, so unless a dam fails, USACE figures to remain popular.
Mohawk is a “dry” dam built for one purpose: Combat Muskingum Watershed flooding. After 78 years, it’s long of tooth and needs shoring up. When Warsaw residents were approached, most were vaguely aware Mohawk is due for repair and largely unconcerned.
“I haven’t heard much,” a middle-aged custom motorcycle rider said. “They’re going to do what they’re going to do, so why worry?”
Village Council member Jesse Fischer said the dam has made problems related to the Walhonding few and far between.
“It takes a significant rain to affect our town,” he said. “We get some yards flooded, and we’ve had problems with ice jams, but that’s about it. The dam needs repair, and they (USACE) brief us from time to time.”
Nick Fischer (Jesse’s Uncle) sees the dam as lifeblood in the town where Fischers have provided mortuary services since 1937, coincidentally the year Mohawk went into service.
“I remember, once as a kid, water coming up onto the bridge,” he said. “It’s not every day you can ride your bicycle on a river. Seriously, though, if it wasn’t for the dam, Warsaw probably wouldn’t be here.”
As an amateur historian involved with the Walhonding Valley Historical Society, Dave Snyder is well versed in Ohio’s Great Flood of 1913 and Mohawk Dam.
“Thirteen ‘Wally’ Railroad bridges were taken out in 1913,” he said. “All were repaired within a month, which is remarkable, and much of Warsaw was moved to higher ground. With the dam, the Walhonding hasn’t flooded Warsaw.”
The historical society maintains a museum on Main Street with a diverse collection that’s impressive for a small village. It occupies a building that was once the Commercial Hotel, and later a sanitarium. In an area that once bustled with activity from a canal and two railways, Warsaw now marks the crossroads of U.S. 36 and Ohio 60, between Mohawk Dam and Coshocton.
“Pictures show that our building took on flood waters up to first-floor windowsills in 1913, but it’s been high and dry since the dam was built,” Snyder said. “We once had 15 inches of rain within 48 hours. I wouldn’t want to see that without the dam.”
In USACE reports on Mohawk Dam, Warsaw and nearby Nellie are sometimes mentioned only between the lines: “The floodplain between the dam and larger downstream population centers can generally be described as broad, gently sloping valleys. Development is sparse.”
Only Nellie lies closer than Warsaw to Mohawk, and the dam is of major strategic importance to its sector of the Muskingum Watershed as the last dam above the Ohio River. It takes water from Mohawk about 66 hours to reach the Ohio River, so when the Walhonding flexes its muscles in Nellie and Warsaw, Coshocton, Zanesville and Marietta are hours or days behind.
“I’ve been told that if the dam failed, the effect would be similar to the Great Flood,” Snyder said. “That we never want to see.”
Virgil Shipley/Mount Vernon News
There was only a small pool of water behind Mohawk Dam on Tuesday but the spillway gates were foaming as water came through under a lot of pressure. The Mohican River was running full down stream through Warsaw. The U.S. Army Corp of Engineers reported the water is only 19.5 feet high.
Part 4: Dams part of Public Works project
WARSAW — When Franklin Delano Roosevelt rolled out his New Deal at the height of the Great Depression, he triggered public works projects on a grand scale not seen since the Great Wall of China. The Public Works Administration had a long reach and billions of freshly-printed dollars to spend, and it provided a perfect opportunity for Ohio to defend against a repeat of the deadly Great Flood of 1913. Fourteen dams were constructed in the Muskingum River Watershed, including Mohawk Dam in neighboring Coshocton County.
FDR may have prioritized job creation over actual benefits, and some saw the PWA as an expensive “make work” program. Millions were unemployed, however. Countless children were getting by on soup thinner than the soles of their shoes. A proud nation was beginning to accept hopelessness as the new normal, and desperate times embraced desperate measures. Today, most agree that the cost effectiveness of PWA’s dam building has been proven many times over.
The Muskingum Watershed Conservation District funnels water to the Ohio River from an 8,000 square mile area, or about 20 percent of the state. Mohawk Dam, in turn, accounts for 20 percent of the watershed’s flood water storage capacity. Estimates by the U.S. Army Corps of Engineers credit Mohawk with preventing $450 million in damages since its 1937 completion, and it has far surpassed an expected service life of 50 years. Despite recent retrofits, however, the earthen dam’s ability to sustain a Probable Maximum Flood event is in doubt. It survived 2005, when winter melt and heavy rains raised the normally placid Walhonding by a menacing record of 80 feet. It would have taken another 35 feet of water to top the 2,300foot-wide earthen dam, but that’s a very remote possibility and secondary concern.
“The most likely failure modes,” according to USACE, “are considered to be from foundation and embankment seepage and piping, which can lead to a catastrophic breach.” In other words, the most likely worst-case scenario is water through the dam rather than over it. Giving Mohawk “PMF strength” will cost as much as $200 million, although a final plan and precise estimate are a year away.
Comparing 1937 and 2015 dollars is useful. Average annual inflation of 3.68 percent sounds modest, but over 78 years it yields a dizzying number of zeros. Dollar-Times.com places the actual $3.3 billion cost of FDR’s building spree at $55.4 trillion today. That would cover 27,000 Mohawk rehabs, so there’s an argument to be made that it’s been a whale of an investment.
Two dams have been added to MWCD’s original 14, including Knox County’s only USACE project, Kokosing Lake on the Upper Branch of the Kokosing River near Fredericktown. MWCD has long since relinquished ownership and management of its dams to USACE, but retains a substantial threefold mission: Providing the benefits of flood reduction, water conservation and recreational opportunities. It is empowered to assess property taxes to raise the “local share” of USACE projects. One rehab project was recently completed at Dover Dam in Tuscarawas County. A Bolivar Dam renewal is in early days, and Mohawk will follow.
MWCD receives taxes from all or part of 18 counties, including neighbors Ashland, Coshocton, Holmes, Licking and Richland. In 2014, a Utica Shale mineral rights windfall allowed MWCD to halve its annual minimum assessment from $12 to $6. About 95 percent of property owners pay the minimum, while some businesses, pay higher rates.
By coincidence, “3Rs” are used to describe both FDR’s 1930s priorities and those of USACE today. The yardsticks of New Deal projects were relief for the unemployed, economic recovery and financial reform. The Army Corps, meanwhile, promises to rehab Mohawk Dam with redundancy, resiliency and robustness as guides. From that point, it figures to serve deep into the 21st century.
Part 5: MWCD facilities fun for everyone
NEW PHILADELPHIA — The Muskingum River Watershed Conservation District at its inception in 1934 and today could hardly be more different. MWCD was created in the spirit of the Conservancy Act, under which Ohioans joined forces to protect water resources and prepare, as best they could, for a repeat of the 1913 Great Ohio Flood.
Without funding, MWCD battled floods only on paper until desperate Great Depression times led to desperate New Deal measures. Federal dollars built 14 dams, and voila — MWCD was in the flood business. Complementary roles of MWCD and the U.S. Army Corps of Engineers have evolved, and USACE now controls the dams while MWCD concentrates on conservation and recreation. The district manages 54,000 acres and 10 reservoirs, and also manages USACE-owned Kokosing Lake near Fredericktown.
With 2,000,000 Ohioans in the watershed, property owners are assessed a whopping 50 cents a month by MWCD. The district provides camping, hunting, boating, fishing, hiking, horseback riding and more, fueled by mineral rights to Utica Shale. Major capital improvements are an enticing lure to easy daytrips from Mount Vernon.
Your closest MWCD facility is likely Kokosing Lake or Pleasant Hill Lake near Perrysville. Also nearby are Atwood Lake in Carroll and Tuscarawas Counties, Charles Mill Lake near Mansfield, and Wills Creek Reservoir along the Coshocton-Muskingum county line. A bit more distant are Beach City, Clendening, Leesville, Piedmont, Seneca and Tappan Lakes.
Four dams, including Mohawk, are dry until needed for flood control. The others are Bolivar, Dover and Mohicanville. Detailed MWCD information is available online at www.mwcd.org.
Following are glimpses at facilities nearest Mount Vernon.
Atwood Lake: With 2,500 land acres and a 1,540-acre lake near Mineral City, Atwood offers facilities for sail and pleasure boaters (25 horsepower maximum), campers, nature lovers and sun worshippers. Amenities include a laundry and store, nature center, beach with changing rooms and boat launches. Overnight visitors can book cabins, RV sites or tent sites. For more information call 330-343-6780.
Charles Mills Lake: Richland and Ashland counties point proudly to their recreational opportunities, and Charles Mill Lake is a chart topper. It’s a comprehensive recreation area with a 1,350acre lake east of Mansfield, and offers swimming, boating, camping, and games from basketball to bocce ball. Call 419368-6885 with questions.
Kokosing Lake: Other than acreage that floods when Mohawk Dam’s gates are closed, Kokosing Lake is Knox County’s only USACE/MWCD site. The dam across the Kokosing’s North Branch was completed in 1970, creating a shallow 154-acre lake. Flood control is by “unregulated outlet structure,” meaning that the river flows unimpeded until intake exceeds outflow capacity. Excess water then backs up until conditions normalize.
Facilities include a boat launch, campground, playground and restrooms. The lake is adjacent to Kokosing Wildlife Area, a prime hunting area. Direct questions to 614-644-3925.
Mohawk Dam: The subject of this series is a workaday “dry” dam without a permanent reservoir, but there is a campground downstream. Ohio 715 crosses the 2,300foot dam.
Pleasant Hill Lake Park: This gem is MWCD’s closest full-service park to Mount Vernon. Located in Ashland and Richland counties, its 850-acre lake has no horsepower restrictions. More than 1,300 land acres provide an outdoors center, marina and campgrounds, plus miles of horseback trails. The park is near Perrysville in a recreation- rich region that also boasts Malabar Farm and Mohican State Park, Wally Road Recreation Area, Indian Powwows and Ohio’s Amish Country.
Wills Creek Lake: With 3,888 prime hunting acres and a 900-acre lake, Wills Creek has great potential, but boating is currently restricted due to sedimentation. The lake is in Coshocton and Muskingum counties, and shares a flood-control distinction with Mohawk Dam. They are the last dams not only before the Muskingum River’s birthplace in Coshocton, but the last dams in the watershed north of the Ohio River.