Invasive Species Statistics

Invasive species cost the USA over $120 billion annually, considering both management expenses and losses due to lack of management. The USA has experienced invasions by over 4000 plant species and 2300 animal species. About half of all pest species in the USA are exotic species, with nurseries, mail order, and the aquarium trade leading the way in new introductions. Just recently a shipment of an invasive snail not yet known in the USA was intercepted on its way to Hartford, CT. These are not trivial numbers.

We know about the impacts to agriculture and lake recreation, but often we get resistance to management from regulatory or private groups concerned over non-target impacts. This may be a valid concern in some cases, but doing nothing also has impacts on non-target species. About 30% of endangered species in the USA got on that list, at least in part, due to invasive species impacts. About 27 of 40 fish that have become extinct over the last century were eliminated by invasive species. After development, invasive species is the largest cause of loss of biodiversity. Doing anything represents risk to some component of an aquatic ecosystem, but so does doing nothing, and this needs to be recognized to get balanced decisions when considering possible management options.

Invasive species experts encourage managers to treat invasions like we do communicable diseases in medicine. Key steps include quarantine, assessment of damage, consideration of treatment options, and implementation of rapid response, rehabilitation, or maintenance. Prevention is important to avoid invasion in the first place or prevent re-infestation, but won’t reverse an invasion in progress.

Variable water milfoil

Zebra mussels

Celebrate Lakes Appreciation Month by telling us about your favorite

Whether it’s memories of idyllic summers spent in a cabin by the lake, learning how to swim or water ski, or morning coffee on the dock in your backyard we all have experiences we savor about our favorite lake. We’d love to hear about your favorite and what makes it so special.  Not only are those reflections fun to read about, but by sharing those experiences with decision makers, groups like NEC-NALMS and our national organization NALMS, can help make the importance of protecting those critical resources more apparent.

So why not leave us a comment to tell us about your favorite and what makes it so special?!

 

Where Drinking Water Comes From

Drinking water comes from the same places as all other water, it just tends to get treated differently to become potable supply. Treatment is required if specific source water conditions are not met. The risks from even natural sources of contamination (e.g., birds, wildlife, erosion) are substantial enough to necessitate treatment in most cases. Yet there is general recognition that drinking water sources need protection, even if that protection is not always provided. A study by the Nature Conservancy revealed that on average about 37% of the land in drinking water supply watersheds is protected from human–derived contamination sources. The other 63% is mostly in private ownership with varying degrees of development (8% on average) and agriculture (15% on average). There is geographic variation, with water supplies for west coast cities having a greater proportion of protected land than for eastern cities, and with northern New England having less developed lands but more agriculture than southern New England. Each case is to some extent unique, leading to differences in the level of treatment necessary.

About 85% of the population of the USA gets its water from public supplies, a percentage that has increased over decades from around 70%. About two thirds of that water is surface supply, a value that has been declining for years from a high of about three quarters. The remainder of the potable supply comes from wells, which have increased in use over the years. This is interesting in that public water supplies are fairly tightly controlled by law and regulation, and many wells are part of public supplies, but private well supplies experience minimal regulatory control. This suggests that an increasing portion of the population is less protected against water quality threats, although it is also true that water from wells is usually of acceptable quality.

About a decade ago 77% of surveyed people did not know where their drinking water came from. That is a scary statistic that suggests a low level of interest in this critical resource. Such lack of knowledge, and presumably concern, is very disappointing but is also consistent with the limited public support for water resource management. Education may not turn everyone into cooperating supporters of better land and water management, but it is a safe assumption that we won’t get more enlightened policy or greater support without such education.


The Breakdown of Water Use

As a society, we use water for drinking, washing, agriculture, industry, landscape watering, and carrying wastes. Overall, agriculture uses about two thirds of all the consumptive use water, but this varies quite a lot across the USA and is less in New England. Thermal cooling and power supply are also major uses of water, exceeding agriculture, but are generally non-consumptive (nearly all the water is put back into the system from which it came). Public supply water, used in residential, commercial and some industrial operations, accounts for about 11% of the total consumed; most of that is used for irrigating ornamental landscapes. Inside the house, water is used for drinking and cooking, but much more is used in bathtubs, washing machines, and toilets.

There is certainly variability over geographic areas, but most of the northern USA has a consumptive use of between 70,000 and 110,000 gallons per person per year. Arid southern areas can use as much as 200,000 gallons per person per day, but most of the difference is landscape watering. If a person used 5 gallons per day for drinking, cooking and washing, all uses where having very high water quality is important, that would equate to 1825 gallons per year, less than 2% of total consumptive use.

This raises some interesting questions. Should we be applying the same high level of treatment to meet stringent standards for the vast majority of water used in ways where that treatment is essentially wasted? The answer appears to be yes, but only because it all arrives at our homes in the same distribution system. Should we be pushing so hard for water conservation in the home when it represents such a small portion of water used? A yes answer is more philosophically satisfying than practical. If irrigation is the dominant use, why is so little effort expended on conservation of that use and so much attention paid to minor uses like bottled water? The answer may be that we have less apparent control, but there is technology to improve irrigation efficiency and we could do without some crops at some times of year to avoid all that water use in arid areas.

A truly comprehensive water policy at federal and state levels should demonstrate a clear understanding of how much water is used for what purpose and apply proper technology and restrictions to conserve a valued resource while recognizing economic limits. We should be pursuing multiple distribution systems that can carry water of the appropriate quality for corresponding uses. Landscape watering needs to be cut by a lot, or even eliminated. Irrigation water conservation should be a top priority. We have a long way to go to reach a sound water management position.


Irrigated cropland.