By Mike Ekberg, MCD manager for water resources monitoring and analysis
You may have heard me say this before—southwest Ohio is water rich. We have abundant, high-quality, water when compared with other parts of our country and the world. Yet, our region is not without challenges in managing water. Here are five water trends that may pose challenges to our community leaders for the foreseeable future.
Precipitation and runoff are trending up
Our region is getting wetter. Mean annual precipitation and runoff (the amount of water that drains off land) in the region are trending up. In the 1960s, mean annual precipitation was around 37 inches per year. Today, mean annual precipitation is a little over 41 inches. That‘s an increase of about 4 inches per year. Not surprisingly, mean annual runoff shows a similar trend.
These trends are good news and bad news at the same time. The good news from a water quantity perspective is our region isn’t likely to experience any long-term water shortages given current water uses. The bad news is our region could experience more frequent flooding outside of areas protected by The Miami Conservancy District (MCD). One thing that’s clear is communities will likely deal with more frequent and intense rain events in the future.
Water use is trending down
According to data compiled by the Ohio Department of Natural Resources, water use for things such as drinking water, manufacturing, and irrigation are declining. Total ground and surface water used in the area that drains to the Great Miami River peaked in the early 2000s at slightly fewer than 600 million gallons of water per day. Water use is currently at about 300 million gallons per day
The decline in water use is a result of several factors, including more water-efficient plumbing fixtures, increased efficiencies in industrial water use, a regional decline in manufacturing, and the closure of the DP&L Hutchings Station power plant. Declining water use poses a challenge for many local water utilities struggling to maintain sufficient revenues to deal with rising infrastructure costs. In the past, water systems often made their financial projections based upon an assumption of rising water demand. This assumption is no longer valid. And yet, public water system infrastructure must be maintained if we want to have safe drinking water. Some water utilities may need to restructure rates to ensure sufficient revenues.
2012 algal bloom on the Great Miami River in downtown Dayton
Nutrient levels in rivers and streams remain too high
Nitrogen and phosphorus levels in many area rivers and streams are too high and affect aquatic life. The most common sources of nitrogen and phosphorus are agricultural fertilizers and human sewage. When nitrogen and phosphorus are present in water at high levels, they fuel excessive algal growth in the rivers where we like to recreate. Recent algal blooms in other parts of the US have been toxic. Agricultural leaders and communities that manage water-reclamation facilities are working to find a solution that cost-effectively reduces nutrients in our rivers and streams.
Deicing agents such as road salt and brine can increase chloride in streams and rivers.
Road salt and fertilizers impact aquifers
Applications of road salt and nitrogen fertilizers are perhaps the two most prolific sources of man-made contaminants to aquifers. Elevated levels of chloride from road salt—and elevated levels of nitrate from fertilizers or failing septic systems—are present in regional aquifers. That’s what groundwater data collected by the United States Geological Survey, the Ohio Environmental Protection Agency (Ohio EPA), and MCD show.
The take-home message is better methods for applying road deicing agents and agricultural fertilizers are needed in areas where regional aquifers are vulnerable to contaminants. Do we know where these vulnerable aquifer areas are? We have a good start. Every public water system in Ohio that relies on groundwater has a defined source water protection area. A source water protection area is a map of all the aquifer areas which provide drinking water to a particular public water system. Those maps can be shared with farmers and road maintenance departments. It may be possible to reduce use or find better methods to apply fertilizers and road salt in these sensitive areas.
Modified stream channels have poor habitat and water quality
Widespread destruction of natural stream habitats continue
It used to be that most people’s image of a polluted stream involved a factory with a big discharge pipe pouring toxic chemicals into the stream. That’s no longer a top water quality threat to regional rivers and streams. According to Ohio EPA, human alterations to the stream channel are perhaps the most widespread cause of stream destruction. Human alterations can mean:
All of the activities listed above disrupt a stream’s natural habitat, which can affect water quality in the places many of us like to recreate. They also create other problems, such as soil erosion and flooding, which can lead to costly clean-up and restoration. Solutions to the problem typically seek to preserve as much of the stream channel in its natural state as possible. Streamside setbacks, conservation easements, and low- impact development practices are tools that can minimize destruction of rivers and streams.
Moving Forward
All of these water challenges can be overcome. The know-how already exists. The key is you and me. Most of these water challenges are the direct or indirect result of how we live our lives—the neighborhoods we build, the services we demand, and the value we place on having clean water. The solutions will require different ways of thinking and different approaches to the way in which our region develops land. Agricultural practices for fertilizers and stream conservation will have to improve. New investments in water reclamation technologies may be needed, and perhaps changes to water rates. Are we ready to embrace those changes? What can you do to prepare? Here’s a short list of ideas: