Healthy streams and waterways are important. After all, clean, healthy streams conjure up images of fly fishing on a glorious summer morning or evening, or a peaceful canoe trip with the family. Both of which are far more “Rockwellian” than my leg-numbing experience of standing in an icy-cold stream to collect data for a stream ecology class on a cold, November day in the Midwest.
So what is the health of the streams in the United States, and how do we define this health? This is what the United States Geological Survey (USGS) set out to understand in their study and subsequent report, “Ecological Health of the Nation’s Streams.”
The USGS’s study covered the years 1993-2005 and examined natural stream ecosystems, urban stream ecosystems, and agricultural stream ecosystems. In evaluating the various ecosystems, they considered the physical, chemical, and biological factors.
The impact of developments to streams when local land use patterns change is not a new area of environmental consulting. Loss of impervious surfaces associated with developments have increased flooding from sheet flow (water that might have otherwise recharged the local aquifer). This runoff can carry with it increased sediment loading and chemical loading…which impact the biological community of a stream…and on and on. This isn’t rocket science, but finding realistic and workable solutions might actually be more complex than rocket science.
Part of the complexity comes from trying to understand non-point sources of pollution (i.e., those not emanating from a pipe) and what is causing the resurgence of algal blooms and dead zones. Recall the restrictions and banning of phosphate detergents in the 1970s that was supposed to bring an end to the historic algal blooms and eutrophication (excessive nutrients).
Without getting into too much detail and turning this blog entry into an environmental consulting journal entry, it’s worth looking at the finding of the recent USGS report as it relates to agriculture. According to the report, there are five specific items listed among the major findings. Number four of five is “Efforts to understand the causes of reduced stream health should consider the possible effects of nutrients and pesticides, in addition to modified flows, particularly in agricultural and urban settings (emphasis added).”
Again, this shouldn’t come as a surprise to anyone who has been following water quality issues and/or agricultural issues. The USGS report states that the following are among the environmental factors impacting stream quality “…tile drains, used to drain subsurface water, route seepage directly to the stream channel rather than allowing gradual infiltration through soils. Water withdrawal for irrigation and channelization can also change the natural flow regime.”
The USGS report further points out that runoff from agricultural lands, “may contain (1) sediment from soil erosion on tilled lands; (2) nutrients from the application of fertilizer and manure; (3) chloride and other salts from irrigation return flows; (4) pesticides used in the past and present to control insects, weeds, rodents, bacteria, or other unwanted organisms; and (5) other synthetic compounds used for varying purposes along with their degradates.”
So, should those in the agricultural community be concerned about the findings in this report? Again, I don’t think there are any great environmental epiphanies in the report.
If there is a caution from this report for the agricultural community it is the “ready, fire, aim” mentality that can sometimes occur when an environmental problem gets the attention of regulators. Genuine solutions need to follow the rigors of science, which means clearly understanding a problem before offering solutions. When environmental problems lack this rigor, they invariably end up costing someone a lot of money and, many times, an undeserved tarnished image. Our peer review service is designed to avoid such potential disasters.
If you would like to read the USGS report, follow this link http://pubs.usgs.gov/circ/1391/pdf/circ1391.pdf
As always, if you have questions or have an environmental consulting need, big or small, contact our office at 248-932-0228.