Low levels of artificial sweeteners present in the aquifer, but what’s safe?

By Mike Ekberg, MCD manager for water resources monitoring and analysis

MCD staff recently found artificial sweeteners in five of 12 groundwater samples. The samples were collected from monitoring wells installed in the buried valley aquifer. This is further proof that many of the chemicals we flush down a toilet, rinse down a sink, or apply to our lawns and gardens ultimately end up in our rivers, streams, and aquifers.

It should be noted that none of the wells sampled in the study are used for drinking water. MCD uses its monitoring wells in the buried valley aquifer to act as a network of sentinels. Samples from the wells provide information on human impacts as well as natural changes in the quality of water over time.

MCD found artificial sweeteners in several groundwater samples (in monitoring wells, not drinking water wells), providing further proof that what we flush down the toilet and rinse down the sink makes its way to our rivers, streams and aquifers.

Artificial sweeteners in groundwater is a concern for two reasons: First, their presence is an indication that human sewage is flowing into the aquifer. Human sewage contains low levels of many contaminants that pass through the sewage treatment process and enter into natural waters. Second, artificial sweeteners are considered to be potential endocrine disruptors because they may interfere with the body’s endocrine system and harm people and animals.

The endocrine system is a chemical messaging system within the human body that regulates organ function. Fortunately, the artificial sweeteners were present in the groundwater at very low concentrations – parts per trillion.

These “endocrine disruptors.” as they are known, are present in many products we use every day, including plastic bottles, detergents, flame retardants, cosmetics, and pesticides. Among the other chemicals MCD found in the samples were:

  • Bisphenol A (BPA), a compound found in plastics.
  • DEET, an active ingredient in insect repellant.
  • The herbicides atrazine, metolachlor, simazine, and sulfometuron methyl.
  • Meclofenamic acid, a drug used for joint and muscular pain and arthritis.
  • Propylparaben, an ingredient in many cosmetics.

BPA is becoming a big concern because human exposure to the compound is widespread. Some animal studies report effects on fetuses and newborns exposed to BPA.

None of the chemicals found exceeded any human health-based standards. The jury is still out, however, on what the standards should be for some of these chemicals. It’s possible that new standards will be set once we better understand how these chemicals affect the human body.

If we want clean, safe water, we may need to support investments in advanced water treatment technologies to remove potentially harmful compounds from water.

 

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Top 5 Regional Water Challenges for the 21st Century

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.Precipitation trending up chart

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

Water trend usage chartThe 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.

Nutrient levels in rivers and streams remain too high

Algal bloom on Great Miami River

2012 algal bloom on the Great Miami River in downtown Dayton

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.

Road salt and fertilizers impact aquifers

top-water-challenges-blog-road-salt

Deicing agents such as road salt and brine can increase chloride in streams and rivers.

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.

Widespread destruction of natural stream habitats continue

top-water-challenges-blog-concrete-channel

Modified stream channels have poor habitat and water quality.

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:

  • Channelizing or straightening a stream channel.
  • Removing the natural vegetation from a streambank.
  • Increasing the impervious surface area that drains into a stream.
  • Damming the stream channel.
  • Developing in a stream’s floodplain.

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:

  • Advocate for federal investment in water infrastructure upgrades.
  • Include water management in short- and long-range community planning.
  • Keep water protection at the top of your community’s priorities.
  • Write local policies that protect water.