Welcome to another edition of DK GreenRoots. Much has been written by me (see my previous handle) about bottled water, water scarcity, deforestation & desertification but precious little about runoff systems, and how ruinous it is to our well being and to those who inhabit the various aquatic ecosystems surrounding us.
However, due to the enormity of this subject I will only post links relevant to US soil (I gathered well over 100 horror stories from around the globe).
In my next DK GreenRoots I will do a roundup of the new technologies which contribute to better water quality.
A 2008 report by the United States National Research Council identified urban stormwater as a leading source of water quality problems in the U.S. Having read extensively on this lately, I would say it is a worldwide problem as "rivers of death" abound in almost every country (btw, the "rivers of death" tag comes from the BBC which does a stellar job of climate change awareness).
Farm waste, the biggest polluter of American rivers, is largely unregulated by many of the laws designed to prevent pollution and protect drinking water.
This quote is attributed to NYT's Charles Duhigg from his explosive article published last week (see also in the roundup below).
As animals graze forages, they inevitably alter the vegetative cover and soil physical properties of pastureland. These alterations may decrease infiltration of water through the soil which, in turn, increases the amount of surface runoff. On lands where poultry waste has been used as a fertilizer for perennial pastures, this increased runoff can deposit high concentrations of nitrogen into water bodies adjacent to pastures, which can be detrimental to the ecology of the water sources.
What is a water runoff? When rain or snow falls onto the good earth, it just doesn't sit there. Eventually it starts moving according to the laws of gravity: some of the precipitation seeps into the ground to replenish underground aquifers & lakes but most of it flows downhill as runoff. Sure, runoff can play its part too as it does keep rivers and lakes full of water, but it also changes the landscape by the action of erosion as flowing water - we have seen some examples lately with the recent downpours of the South - has such tremendous power.
Meteorological factors affecting runoff:
• Type of precipitation (rain, snow, sleet, etc.)
• Rainfall intensity
• Rainfall amount
• Rainfall duration
• Distribution of rainfall over the watershedS
• Direction of storm movement
• Antecedent precipitation and resulting soil moisture
• Other meteorological and climatic conditions that affect evapotranspiration, such as temperature, wind, relative humidity, and season.
Physical characteristics affecting runoff:
• Land use
• Vegetation
• Soil type
• Drainage area
• Basin shape
• Elevation
• Slope
• Topography
• Direction of orientation
• Drainage network patterns
• Ponds, lakes, reservoirs, sinks, etc. in the basin, which prevent or alter runoff from continuing downstream.
Runoff may also be classified according to speed of appearance after rainfall or melting snow as direct runoff or base runoff, and according to source as surface runoff, storm interflow, or ground-water runoff. As the runoff moves, it picks up and carries away natural and human-made pollutants, depositing them into lakes, rivers, wetlands, coastal waters, and certainly affecting the underground sources of drinking water. These pollutants include (info taken from the EPA):
Excess fertilizers, herbicides, and insecticides from agricultural lands and residential areas;
Oil, grease, and toxic chemicals from urban runoff and energy production;
Sediment from improperly managed construction sites, crop and forest lands, and eroding streambanks;
Salt from irrigation practices and acid drainage from abandoned mines;
Bacteria and nutrients from livestock, pet wastes, and faulty septic systems.
We can't talk about water runoffs without watersheds.
A watershed is the area of land where all of the water that is under it or drains off of it goes into the same place. John Wesley Powell, scientist geographer, put it best when he said that a watershed is:
"that area of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course and where, as humans settled, simple logic demanded that they become part of a community."
Watersheds come in all shapes and sizes. They cross county, state, and national boundaries. In the continental US, there are 2,110 watersheds; including Hawaii Alaska, and Puerto Rico, there are 2,267 watersheds.
As watersheds are urbanized, much of the vegetation is replaced by impervious surfaces, thus reducing the area where infiltration to ground water can occur. Thus, more stormwater runoff occurs - runoff that must be collected by extensive drainage systems that combine curbs, storm sewers and ditches to carry stormwater runoff directly to streams. More simply, in a developed watershed, much more water arrives into a stream much more quickly, resulting in an increased likelihood of more frequent and more severe flooding.
Drainage ditches to carry stormwater runoff to storage ponds are often built to hold runoff and collect excess sediment in order to keep it out of streams.
What to do, what to do? We can all work together to reduce and prevent nonpoint source pollution. Some activities are federal responsibilities, such as ensuring that federal lands are properly managed to reduce soil erosion. Some are state responsibilities, for example, developing legislation to govern mining and logging, and to protect groundwater. Others are best handled locally, such as by zoning or erosion control ordinances. And each individual can play an important role by practicing conservation and by changing certain everyday habits. Below are a few samples of how water runoffs affect life:
Massachusetts Rules Blamed for Outdated Water Runoff Systems:
Environmentalists and manufacturers of storm-water treatment systems in Massachusetts say that outdated regulations in the state are undercutting an ambitious initiative to clean up the Charles River watershed and other waterways. Source
Health Ills Abound as Farm Runoff Fouls Wells:
All it took was an early thaw for the drinking water here to become unsafe. There are 41,000 dairy cows in Brown County, which includes Morrison, and they produce more than 260 million gallons of manure each year, much of which is spread on nearby grain fields. Source
Polluted Runoff Plagues New York's Beaches:
American beach-goers are too often greeted by polluted water that
threatens public health, as the number of closing and advisory days at ocean, bay and Great Lakes beaches exceed 20,000 for the fourth consecutive year, according to the 19th annual beachwater quality report, Testing the Waters, released today by the Natural Resources Defense Council (NRDC). Source
AP Impact: Gov't stands by as mercury taints water:
California - An investigation by ecologist Fraser Shilling of the University of California at Davis, Yolo County, found that over 550 abandoned mercury mines throughout central California are polluting major waterways and making fish unsafe to eat. Source
Dairy runoff in our tap water:
Big dairies, big problems: reporter Charles Duhigg of the New York Times has been on the rampage these past few weeks with a series of great articles highlighting the need for better government regulation, oversight and enforcement of clean water laws. Source
GreenRoots is a new environmental series created by Meteor Blades and Patriot Daily for Daily Kos. This series provides a forum for educating, brainstorming, discussing and taking action on various environmental topics.
Please join a variety of hosts on Sunday, Tuesday, and Thursday at 6 pm PDT. Each Wednesday is hosted by FishOutofWater.