MCD dams storing water more often than ever before

By Mike Ekberg, manager of water resources monitoring and analysis

MCD flood protection dams are storing water more often than at any other time since the dams were completed almost 100 years ago. That’s because the Miami Valley’s climate is getting wetter. Can the flood protection dams handle more rain?

A rising 30-year average precipitation
Average annual precipitation in the Miami Valley for the 30-year period of 1951 to 1980 was about 37 inches a year. Average precipitation for the last 30 years (1991 – 2020) has climbed to almost 42 inches a year—a nearly 14 percent Increase.

Average precipitation increased for every month except August. Average precipitation for the months of January, April, May, June, July, September, October, November, and December increased by more than 10 percent. October showed the largest increase in average precipitation—more than 30 percent.

With increased precipitation comes increased runoff and higher river flows. When river flows become high enough to be a flood threat, our flood protection dams go into action and begin to store water. When any one or more of our dams begin to store water, we call that a “storage event.” Storage events at each of the dams are recorded separately. So if all five dams are in storage at the same time, it is counted as five storage events. The storage event ends at each dam when that dam is no longer holding back any water.
Waters stored behind dams more frequently
MCD tracks the number of storage events that occur each year. The following chart shows the number of storage events that have occurred during each full decade since the dams were completed in 1922. You can see how the number of storage events has climbed throughout the decades of the 1990s, 2000s, and 2010s. Prior to the 1990s, no single decade had more than 200 storage events. The number of storage events in the last three decades all exceeded 200, and storage events for the decade of the 2010s exceeded 300.  

More frequent large storage events
Increasing frequency of storage events at MCD dams is one thing. What about the size of those storage events?

The answer seems to fall in line with simple odds. All other things being equal, the more storage events there are, the greater the chance of having really large events.

We rank storage events based upon the total storage volume of water held behind our five dams. The following chart shows the number of events by decade that rank in the top 100 largest storage events. You can see that 32 of the top 100 largest events took place in the last 20 years. The decades of the 2000s and 2010s each had 16 storage events that ranked in the top 100. Only the 1950s comes close to this number. That decade produced the largest storage event since the MCD flood protection system was built—the January 1959 event.

MCD flood protection system is resilient
The climate of the Miami Valley is changing and getting wetter. Flood risk is increasing. Fortunately, the MCD flood protection system is well designed to respond to these changing conditions in the Miami Valley.

The system was designed to withstand a very large event—the 1913 flood event plus 40 percent more runoff (which is the equivalent of 11-14 inches of rain over three days). The January 1959 event was the largest storage event since the completion of the flood protection dams. The 44.8 billion gallons of floodwater the dams held back used only 16 percent of the five dams’ total storage capacity. That means 84 percent of the capacity has never been used but is there if we need it.

The MCD flood protection system is resilient—based on design, capacity and performance. Resiliency is a good thing to have in a rapidly changing world.

Learn more about the flood protection system.

2020 Precipitation: Up, Down and All Around

By Mike Ekberg, manager of water resources monitoring and analysis

Note: At MCD, we track water movement into and out of Great Miami River Watershed over long periods of time, spanning decades. The records generated by our observer precipitation stations, stream gages, and observation wells allow MCD staff to examine long-term trends in water resources. Water enters the watershed as precipitation (rain, sleet, hail, and snow), and it exits the watershed through evaporation, plant transpiration, and runoff.

2020 will go down in history as anything but a normal year. And that goes for our region’s precipitation, too.

The Great Miami River Watershed started the year wet, with four of the first five months experiencing above-average precipitation. And then the tide turned, and the watershed saw drier-than-normal conditions for five of the last seven months.

Drought conditions existed in parts of the watershed from early July until mid-August and returned to parts of the watershed in mid-September, lingering until late October. October was uncharacteristically wet, averaging 5.02 inches of precipitation or 2.06 inches above average.

Despite the many drier months, total precipitation for the year was 2.26 inches above normal for a total of 42.56 inches, continuing a long-term trend of increased annual average precipitation.

The chart represents an average of 42 precipitation stations MCD operates.

Average Annual Precipitation Increasing

The chart below shows how the 30-year average annual precipitation for the watershed has changed since 1945. Note the upward trend in precipitation that began sometime around the late 1980s to early 1990s.

This graph shows the moving average 30-year precipitation for the Great Miami River Watershed.


The higher-than-average amounts of precipitation in 2020 led to above-average runoff. Runoff is that portion of precipitation which ultimately ends up in the Great Miami River. Annual runoff for the Great Miami River was 16.01 inches in 2020—1.4 inches above average.

Two High-Water Events in the Top 100

MCD recorded 12 high-water events last year—well above the average of eight. MCD defines a high-water event as a time when one or more of the following occurs:

  • Any one of MCD’s five flood protection dams goes into storage—when the conduits slow the flow of water. This is approximately when the conduits are flowing full.
  • The Great Miami River in any one of the 10 cities MCD’s system protects reaches an action stage as defined by MCD’s Emergency Action plan.

The largest high-water event in 2020 took place from May 19-23 when all five MCD dams together stored a peak of 9.2 billion gallons (28,200 acre-feet) of water. This event ranked as the 69th largest high-water event in MCD history. MCD also recorded its 96th largest event in 2020.

While no monthly or annual records were set in 2020, we did experience two top 100 high-water events. The above-average total precipitation and runoff as well as the higher-than-average high-water events continue to provide evidence of a changing climate in southwest Ohio. A climate that seems to be getting wetter with time.

Got Water Info?

Whether you’re looking to learn more about the region’s water or searching for specific water information, the answers may be a click away.

Miami Conservancy District (MCD) offers easy-to-access fact sheets, videos, live water data, reports and infographics—all about water—on our website We have resources for river users, well owners, scientists, city/county staff, and someone just learning about rivers and groundwater.

Are you local government staff or an elected official? Read case studies of how MCD has helped cities, counties, and other organizations.

Are you a scientist looking for in-depth research studies and reports? We track and report on groundwater quality and quantity, nutrient and biological conditions in rivers, and other water trends.

Are you a private well owner looking for information and guidance about testing your well? We help sponsor Test Your Well events and provide testing information. (Please test your well regularly.)

Looking for specific details on rivers and their condition? You can download infographics about the major rivers and streams in our region and their conditions. You can also access live data on rivers and groundwater

Interested in recreation and want to know if the water is safe? Find out more about bacteria levels and high-water levels by clicking here and here.

Read about 10  easy things you can do around your home or business to protect our region’s water resources. 

Want to become actively involved with water? Try volunteering for the annual river trash clean-up days and attend the quarterly meeting of water stakeholders.

And don’t forget our 2-minute videos about our region’s water. Share them with your friends and family!

Our Region’s Water – What it means for our health and our economy

Where do we get our water from in the Miami Valley?

Changing Weather Patterns – What you need to know for the future

Be Water Wise – Things you can do to protect our Rivers and Streams 

You can also follow us on Facebook, Twitter, and Instagram for current news.

Let us help you access the information you need/want whether you’re just beginning to take an interest in water or are a water expert.

Happy New Year!

Dam concrete repair necessary to ensure future performance

By Don O’Connor, P.E., chief of construction and planning

MCD is committed to keeping the dams and other flood protection structures operating safely and properly for your protection. To that end, we are nearing completion on a $2.61 million project to improve concrete at Lockington Dam. Over the last 13 months, MCD’s contractor has removed and rebuilt up to 15 feet of concrete on top of the dam’s upstream and downstream right bank wall as well as repaired concrete on the face of the wall.

This project was necessary. While there was little danger that the wall might fail during a high-water event, there was significant deterioration. Had we waited another 10 or 20 years, the extent of damage would have been more severe and much more expensive to repair. Addressing this rehabilitation in a timely manner is financially responsible. And it could be dangerous if put off for too long.

Over the last 13 months, MCD’s contractor has removed up to 15 feet of concrete on top of the Lockington Dam upstream and downstream right bank wall and repaired concrete on the face of the wall.

Freeze/thaw cycles damaged the concrete

Over the decades, water has seeped into the walls through joints and cracks. That water has been a destructive force because of the innumerable freeze/thaw cycles that caused the water to expand and turn into ice. This caused extensive damage to the outer surface of the concrete walls.

The last significant concrete repair at Lockington and the other four flood protection dams took place in the 1970s with a material called shotcrete. The shotcrete repaired the previous surface deterioration, but the freeze/thaw cycles eventually damaged the material and caused some of it to detach from the walls. The Lockington Dam shotcrete was beyond its useful life and needed to be replaced.

With the current repair, MCD’s contractor also installed an underground drain system behind the concrete wall to keep rainwater and snowmelt from seeping into the wall joints. The drains are designed to help prevent the damage caused by the freeze/thaw cycles.

The repair work at Lockington Dam is the first in a series of projects MCD
will need to complete at its dams.

More work to come

Concrete repair at Lockington Dam is the first of many concrete projects to come. MCD is planning additional work at Lockington Dam along the left wall. Each of the dams will likely need similar work. Studies are planned for the other four dams to determine the extent of repairs needed and to prioritize work for future projects.

The right-wall project at Lockington was the culmination of years of work and monitoring. MCD frequently inspects its dams. Those inspections began to show a need for more detailed investigation/structural analysis. That analysis helped MCD understand the scope of work needed at the dam, leading to the design and construction.

These kinds of projects are years in the making. But it’s important we take the time to follow a logical process, determine the need, and complete it as cost-effectively as possible.

Don O’Connor is MCD’s chief of construction and planning. He joined MCD in 2018 and is a licensed professional engineer.

What Will 2020-2021 Winter Bring?

By Mike Ekberg, manager of water resources monitoring and analysis

It’s the beginning of November and winter is just around the corner. What kind of a winter can we expect in the Miami Valley this year? 

Winter 2020–2021 might be wetter than normal with frequent storm events tracking across our region. Wetter than normal means above-average winter precipitation, including rain, sleet, and snow. One factor that favors this outcome is the forecasted presence of a strong La Niña pattern in the tropical Pacific Ocean this winter.
Credit –
La Niña present in the tropical Pacific Ocean
La Niña is an atmospheric pattern characterized by stronger-than-normal trade winds and cooler-than-normal ocean temperatures in the equatorial Pacific Ocean. These conditions are currently present, and the National Oceanic and Atmospheric Administration (NOAA) is forecasting this pattern to persist and strengthen as we move through the winter months.

How does an atmospheric phenomenon such as La Niña thousands of miles away in the tropical Pacific Ocean influence winter weather in the Miami Valley?
Credit –
Wetter-than-normal winter conditions favored in the Miami Valley
The answer lies in La Niña’s influence on the position of the polar jet stream across North America. According to the National Weather Service, jet streams are narrow bands of strong wind in the upper atmosphere that blow from west to east. The polar jet stream often marks the boundary between cold and warm air masses across North America, and it often acts as a transport mechanism for storm systems across the United States. La Niñas tend to cause the polar jet stream to dip south over the Midwest and the Ohio Valley. This creates favorable conditions for winter storm systems to track across this region. The result is lots of moisture delivery, leading to above-average precipitation.

So there you have it, we can bank on a wetter–than-normal winter this year, correct? Not so fast, La Niña is just one of many factors impacting winters in the Miami Valley.
La Niña can lead to above-average precipitation in winter.
Other factors influence local weather, too
La Niña events tend to be persistent, lasting six to 18 months. There are other global atmospheric circulation patterns or teleconnections such as the Pacific/North American (PNA), Arctic Oscillation (AO), and the North Atlantic Oscillation (NAO) which fluctuate on shorter time scales. These teleconnections also influence the path of the jet stream across the United States and may interact with La Niña amplifying or canceling out its impact. Predicting these teleconnections patterns can be difficult.

Local factors such as soil moisture conditions and snow cover can also influence winter precipitation in the Miami Valley. Long-term climate trends may also play a role.

Obviously, there is a lot of uncertainty when it comes to making predictions about how winter 2020–2021 will turn out. Still, it’s fun to look at all the factors and give it a shot!

MCD ready to respond no matter what winter 2020-2021 brings
No matter what this winter brings, there is one thing the Miami Valley region can count on. MCD is ready to respond to whatever weather comes our way. The MCD flood protection system has been in place for nearly 100 years, significantly reducing flooding risk in cities along the Great Miami River. If this winter turns out to be wetter than normal as predicted, MCD will be ready to respond.

Earn your Water Diploma – Enroll at Great Miami U!

Win a gift card to your favorite local brewery or coffee shop

At most universities you pay to learn. At Great Miami U, we’ll pay you (if we pick your name in a drawing of all our graduates). Earning your degree from Great Miami U is free and easy. And better yet, it only takes a few minutes!

The Miami Conservancy District (MCD) is launching the Great Miami Watershed University, or Great Miami U, today as part of the national Value Water campaign to raise awareness about the importance of water and the often invisible water challenges facing our country.

We’re fortunate in this region to have plenty of water. You turn on the faucet and water comes out. It’s hard not to take water for granted when it’s always there for us. But how much do you really know about the region’s water? We’ve got the basics ready for you in a new and fun way to learn.

You can earn your diploma in three easy steps.

  1. Click here to get started.
  2. Watch four 2-minute videos about water.
  3. Take a 4-question exam to test your knowledge.

You will then be registered to win a $100 gift card to the local brewery or coffee shop of our choice. We’ll even email you a diploma to print.

EARN A BONUS CHANCE TO WIN – Take a photo of yourself with your diploma and post to Facebook, Twitter or Instagram with the hashtag #GreatMiamiU and we’ll enter you a second time.


Do a little (septic system maintenance) to save a lot!

By Mike Ekberg, manager for water resources monitoring and analysis

If you could spend less than $100 a year to avoid a $7,000 home repair expense, you’d do it wouldn’t you?

Consider this: It only costs about $250 to $500 every three to five years to maintain a septic system. But it can cost up to $7,000 or more to repair or replace it. Plus, a poorly maintained septic system can contaminate groundwater/drinking water and spread disease.

You can’t put a price on the health and safety of your family.

What is a septic system?
Septic systems are highly efficient, self-contained, underground wastewater treatment systems. They are commonly found in rural areas and often consist of a septic tank and a drainfield.

Do you have a septic system? You probably do if:

  • You use well water.
  • The water line coming into your home does not have a meter.
  • Your neighbors have a septic system.

Septic Smart Week
Septic Smart Week is Sept. 14-18. It’s a good time to have your system maintained and review ways to keep your system working well.

Maintain your septic system
Inspect and pump regularly
In general, your septic system should be inspected every one to three years and pumped every three to five years by a certified septic system professional.

Use water efficiently to avoid overloading the system
Consider using high-efficiency toilets and showerheads. When using the washing machine, be sure to select the proper load size to avoid using more water than needed.

Flush with care. Don’t flush anything besides human waste and toilet paper. Never flush:

  • Paints
  • Chemicals
  • Medications
  • Feminine hygiene products
  • Dental floss

Take care at the drain.

  • Never pour cooking oil or grease down the drain.
  • Never pour oil-based paints or solvents down the drain.
  • Eliminate or limit the use of a garbage disposal.
  • Never park or drive on your drainfield.
  • Plant trees an appropriate distance from your drainfield. A septic service professional can help you with the property distance.
  • Keep roof drains, sump pumps and other rainwater drainage systems away from your drainfield areas. Excess water can slow or stop the wastewater treatment process.
  • View these SepticSmart Week Quick Tip videos on the importance of properly using and maintaining your septic system.

Information for this blogpost was taken directly from the Environmental Protection Agency’s “A Homeowner’s Guide to Septic Systems”

Giving the Stillwater River Some Love

By Sarah Hippensteel Hall, Ph.D., manager of watershed partnerships

If you haven’t visited the Stillwater River firsthand, it is time you did. The Stillwater River is a special place to fish, paddle, or just enjoy some beautiful scenery.

Ohio’s only National Water Trail and State Scenic River

Designated as both a National Water Trail and a State Scenic River, the Stillwater River and Greenville Creek system are the only river segments in Ohio that have been awarded both of these special distinctions.

Ohio’s scenic river program recognizes high quality natural streams and helps protect them for future generations. The National Park Service’s National Water Trail program recognizes rivers and streams with plentiful public access for river recreation. Together, that makes the Stillwater River one of the best Ohio has to offer.

Greenville Falls

Premier outdoor recreation 

The Stillwater River and its tributaries offer diverse recreation fun.

  • World-class fishing, including some of Ohio’s premier smallmouth bass habitat
  • 60+ miles of flatwater for beginning and intermediate paddlers
  • Beautiful riverside parks managed by Darke County Park District, Miami County Park District, and Five Rivers MetroParks
  • Fun nature education at Brukner Nature Center in Troy, and Aullwood Audubon in Dayton
  • Scenic waterfalls on Greenville Creek

Stay Safe

And anytime we talk about river adventures, we need to talk about river safety. A few small steps can ensure your next experience on the Stillwater River—or any river for that matter—is a fun and safe one.

  • Do not enter the water when river levels are high or water is moving fast. Most people underestimate the power of water.
  • Always wear a life jacket while paddling.

Use our Stillwater River water trail map to learn more about staying safe on the river.

She is putting on the most important piece of river gear. Always wear a life jacket when paddling the Stillwater River.

The health of the Stillwater River

So the Stillwater River offers exceptional river recreation. But what about the condition of the river?

When Ohio designated the Stillwater River as a Scenic River in 1975, it was considered to be in “excellent” or “good” condition. As with virtually every water body in the country, land uses in recent years threaten the water quality and condition of the habitat. Despite the challenges, the Ohio EPA reports that 52 percent of the Stillwater River and its major tributaries meet Ohio water quality standards.

One of the most common threats to the Stillwater River is nutrients. Nitrogen and phosphorus enter waterways when it rains, impacting water quality. Both are found in fertilizers, animal waste, sewage, and wastewater. These problems can be reduced by fencing livestock out of streams and rivers, better fertilizer management, properly maintaining septic systems, and improvements to wastewater treatment.

The Stillwater River and its tributaries have also been heavily impacted by physical, man-made changes. Removal of stream side forests can increase erosion of the stream banks. When the shape of the stream is changed from a natural, meandering shape to a straight channel, habitat is destroyed.

More than half of the Stillwater River and its tributaries meet Ohio water quality standards.

MCD and the Stillwater River

Keeping rivers healthy is a big part of MCD’s water stewardship efforts. We collaborate with schools, communities and local groups to protect the river. We:

  • Track nutrient and other pollutant levels in the Stillwater River.
  • Sponsor trash cleanups on the river.
  • Educate homeowners on proper maintenance of home sewage treatment systems.
  • Partner with communities that manage wastewater treatment to explore new approaches to wastewater management.

We’re working to keep the Stillwater River healthy for you, your family and generations to come. You can help with these simple water wise actions. Let’s give the Stillwater River some big love in return for all it gives us.

Bike trail and river conditions just a couple clicks away

By Sarah Hippensteel Hall, Ph.D., manager of watershed partnerships

Before you head out on your next cycling or paddling adventure along the Great Miami, be sure to check out bike trail and river conditions. It’s always best to know before you go!

The live Bike Trail and River Conditions Map on the Great Miami Riverway website helps you understand river water levels and whether or not bike trail sections may be under water after rain events. And now, the Riverway has launched a River Water Bacteria Levels Map to provide information on river water quality.

Bike Trail Conditions

It’s always a good idea to check bike trail conditions before you go, especially if we’ve seen rain lately. Some trails are located within the levee systems that protect our cities from high water—and that means trail sections might be under water after rain or storms. You don’t want to leave the comfort of your house only to find out that a section of your favorite trail is covered with water.

The map’s color-coded symbols are set up just like a traffic signal, making it easy to read.




River Conditions

You can also check the river water levels to see if water conditions are appropriate for your experience level.




When paddling, it’s also a good idea to consider:

  • Wind
  • Weather
  • Temperature
  • Floating debris
  • River current
  • Boat size
  • Skill level
  • Ability to launch safely


And keep these safety tips in mind:

  • Always wear a life jacket.
  • Never paddle alone.
  • Tell someone where you are going and when to expect you back.
  • You can find more safety tips here.

River Bacteria Levels – How High Is Unsafe for Recreation?

New to the Great Miami Riverway website is a map that helps river users understand water quality conditions and potential bacteria levels. The map promotes public health and safety by helping you decide when the water is safe to paddle.




Rain events can cause bacteria levels in river water to rise to an unsafe level for human contact. Bacteria can get into the river water from a variety of sources, including pet waste, storm sewers, septic tanks, and farm fields. And that bacteria can make you sick if you swallow any river water.

Using research conducted by the Miami Conservancy District, this Riverway web app estimates the concentration of E. coli bacteria, an indicator of fecal pollution, during different weather conditions. The Ohio EPA advises that recreation waters are unsafe for human contact when E. coli is > 298 colony counts per 100 mL of water.

Using these maps will help ensure your next adventure is not only fun but safe.

Find your way—safely—along the Great Miami Riverway!

This blog is also published on the Great Miami Riverway website.

PFAS Part III — Strategies

By Mike Ekberg, manager of water resources monitoring and analysis

In Part I, we looked at what per- and polyfluorinated alkyl substances, or PFAS, are and why you should care. In Part II, we looked at their presence in local drinking water. In this final post, we look at the strategies for dealing with PFAS.

Per- and polyfluorinated alkyl substances or PFAS are a group of manufactured chemicals widely used in consumer products such as cookware, paper wrappers for fast food, stain repellants, and fire-fighting foams. These chemicals gained widespread attention nationally as well as locally when they began to be detected in the drinking water of some public water systems.

A lack of a cohesive nationwide approach for determining appropriate PFAS levels and actions has resulted in a wide range of state standards for different PFAS compounds. This adds to the confusion for consumers trying to determine how much PFAS in their drinking water is safe.

Three strategies for dealing with emerging contaminants
It’s likely that chemicals, such as PFAS, originating from consumer products will continue to be detected in natural waters as well as treated drinking water. It’s also likely that as consumers of public drinking water, we will continue to prefer that these types of chemicals not be present in our drinking water. With that in mind, here are three strategies that could help.


1. Study chemicals in the marketplace and replace toxic substances with less toxic alternatives

It’s estimated that approximately 2,000 new chemicals are introduced into the U.S. market each year. Few of these chemicals are evaluated for their toxicity and potential environmental impacts in a timely manner.

The Toxic Substances Control Act (TSCA) requires USEPA to evaluate new chemicals for safety, but historically, the agency did not have the necessary authority or resources to keep up with this task.

Congress recognized these deficiencies and, in 2016, it passed the Frank R. Lautenberg Chemical Safety for the 21st Century Act. The act made some important improvements to the process for ensuring safety of chemicals in the marketplace.

Key provisions of the act:

  • Mandates safety reviews for chemicals in active commerce.
  • Requires a safety finding for new chemicals before they can enter the market.
  • Replaces TSCA’s burdensome, cost-benefit safety standard—which prevented the EPA from banning asbestos—with a pure, health-based safety standard.
  • Explicitly requires protection of vulnerable populations like children and pregnant women.

The act, however, only required USEPA to begin risk evaluations on 20 chemicals within the first three–and-a-half years of its implementation. Twenty is a very small number when compared to the number of new chemicals entering the market each year. If we can reduce or prevent chemicals that have a high potential of impacting water quality from entering the marketplace, we will have done our water resources a great service.

2. Source water protection is more important than ever

All too often decisions about how to develop land over sensitive aquifers and in close proximity to municipal wellfields are made without appropriate consideration about how the development and activities taking place on that development could impact water quality.

As consumers of public drinking water, we expect that our local governments and public water utilities engage in vigorous efforts to protect their supply of water. This means that economic development plans and activities must align with protection of our source of drinking water.

This alignment implies that some areas over sensitive water resources are not suitable for certain types of development that could pollute or threaten good water quality. A well thought out and proactive source water protection plan is the key to making this happen.

Granular activated carbon Credit:

3. Investment in advanced water treatment may be needed

Public expectations often drive investment in new technologies. As new analytical methods lower thresholds for detecting contaminants, water utilities and regulatory agencies will have to deal with the discovery of new chemicals in water. While the concentrations may be extremely small, community members will most likely feel safer if these chemicals are not found in their drinking water.

Water utilities may be faced with the decision to provide advanced water treatment, such as membrane filtration and granular activated carbon filtration, but this level of treatment can be expensive and could raise water rates.

MCD – Helping our region to be water resilient
The Miami Conservancy District (MCD) is committed to helping our region successfully respond to the water challenges that chemicals such as PFAS present to the water resiliency of our communities.

At the request of Congressman Mike Turner, MCD and a group of community and business leaders retained a consultant to assess the City of Dayton’s public water system and all interconnected utilities.

MCD is also working with the United States Geological Survey to evaluate the occurrence of PFAS in groundwater outside of the Dayton metro area. These efforts will help our region protect water for now and into the future.