WILL THE RIVERS CLAP THEIR HANDS?

Rivers are a primary source of supply for many water utility systems. Such utilities are responsible to treat river water in compliance with applicable safe drinking water regulations. As rivers and their tributaries meander through agricultural land, they are susceptible to farm field soil erosion and fertilizer runoff. Perhaps the most troublesome constituents of such runoff are the nitrates. In the United States, there are strict limits on the permitted levels of nitrates in drinking water, which impose in many cases costly treatment protocols.

For example, in its 2014 annual report, the Minnesota Department of Health indicates that agricultural related nitrate pollution is a growing threat to the state's drinking water from all sources. The report states: "Roughly half of Minnesota's land is in agricultural production, primarily in the southern and western parts of the state. Up to 20 million acres of Minnesota is in row crop production annually. Row crops, which include corn, soybeans, sugar beets, and potatoes, are a major contributor to Minnesota's economy. However, since soils in row-crop production can lose nitrate during the non-growing season, these lands are the biggest influence on Minnesota's ground and surface water nitrate levels." (p.7)

Farm soil erosion is another issue for rivers. According to a published report, to mitigate erosion, farmers are switching to no till farming, a practice of planting crops without tillage of the soil. Stubble from prior crops is left on the ground. The new crop is planted by drilling seed into the soil without disturbing the ground by tilling. Accordingly, this practice tends to hold soil in place.*

So, could no till farming be the answer for both erosion and runoff control? Maybe not, according to another published report. It states that researchers have found that fields managed by conventional and turbo-tillage practices can produce lower concentrations of pollutants in runoff than those managed by no till practices.**

Maybe further research will conclude that both new seed and fertilizer could be drilled into the soil, leaving the surface otherwise undisturbed. This approach, of course, could cause increased costs for agricultural interests. But it also could assign costs to the cost causers and reduce treatment costs for utilities and their customers. Perhaps, an alternative approach could be no till practices for erosion control and more modest and efficient application of fertilizers. Whatever, with further research, maybe some day rivers will have less concern over erosion and runoff, and will clap their hands.

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*Lutey, Billings Gazette, republished in
Rapid City Journal, April 27,2015,p.A8

**Environmental Science & Technology,
November 20, 2012

AS THE RIVER TURNS

In March, USEPA issued its findings from a survey of thousands of miles of rivers and streams through out this country. It concluded that 55% of the miles are in poor condition for aquatic life. The assessment includes the following conclusions:

1. Some 27% of the rivers and streams have excessive levels of nitrogen and 40% have high levels of phosphorus. These constituents form "nutrient pollution" which causes adverse increases in algae and adverse decreases in oxygen in the water.

2. Some 24% of rivers and streams are considered poor due to loss of healthy vegetative cover needed to mitigate erosion, remove pollutants and maintain water temperatures.

3. Some 9% of miles contain high levels of bacteria, which can be unsafe for swimming and other recreation.

4. More than 13,000 of miles contain fish with high levels of mercury, which may be a health issue for humans.

In early April, a report funded by the National Science Foundation describes a record breaking 2011 algae bloom on Lake Erie. Such blooms in freshwater can result from runoff containing nitrogen and phosphorus, with high precipitation, poor lake circulation and warm temperatures. Decomposition of algae and aquatic plants deplete oxygen in the water needed for aquatic life.

The EPA's Office of Water Acting Assistant Administrator is quoted as stating: 'We must continue to invest in protecting and restoring our nation's streams and rivers as they are vital sources of our drinking water , provide many recreational opportunities, and play a critical role in the economy." (EPA Release, March 26, 2013)

So, what have EPA and other governmental agencies have done over the past 40 years to protect rivers and streams from such adverse environmental impacts as described in these reports and to enhance their drinking water and recreational potential uses? Maybe it is time for less reliance on promised action; and instead time for us to actually take ownership of what we own.

DEALING WITH NITRATES IN DRINKING WATER SOURCES

In the United States, strict limits have been adopted on the permissible level of nitrates in finished water provided by public water supplies. These limits were developed particularly out of concern for infants who may be vulnerable to higher nitrate levels in drinking water.

Nitrates in ground water and surface water tend to be associated with agricultural areas where chemical fertilizers and animal manure appear to be the primary cause.

In March, 2012 the University of California at Davis released a study which allegedly found that nitrate contamination of ground water is pervasive in certain agricultural communities, where some wells have exceeded the standard. According to the study, nitrate leaching from agricultural land has caused 96% of current ground water contamination.

Nitrate impacts on surface waters such as rivers can occur from storm water farm run-off and from farm drain tiles, particularly in significant Spring rain events.

To deal with elevated nitrate levels in source waters, utilities may face complex challenges and resulting costs...costs that will have to be recovered from their customers. Installing effective treatment facilities particularly may be expensive for smaller water systems. Seeking alternative ground water supplies may not be feasible if nitrates have spread in an aquifer.

One midwest water utility which uses river water as its source of supply found that nitrate levels in the river exceeded the standard primarily only during Spring rain periods. So, it acquired an nearby empty gravel quarry to store river water during low nitrate periods, which then is blended with higher nitrate Spring river water to achieve compliance with the standard.

The same midwest utility also became proactive to work with the farm community to educate as to the impacts of over-fertilization of crop land. Through such an organizing effort, farmers began to understand not only such impacts but also the potential savings from reducing the types or quantities of fertilizer applications.

Along the same lines, a California trade group representing fertilizer manufacturers and retailers has stated that the California Department of Food and Agriculture has developed "best management practices" to mitigate nitrate contribution from fertilizer by optimizing fertilizer usage, matching nutrient supply with crop requirements to minimize nutrient losses. Such practices now may include split application of fertilizer based soil and plant testing and use of sensors for more precise nitrogen management.

So, it appears that parties concerned with both potential causes and effects of nitrate levels in drinking water sources are trying to deal with the issue.