Water woes

“Renewable? Water woes require drastic measures”, published 11/08/2007, The Hook

By MARLENE CONDON | MARLENECONDON@aol.com
Published online 8:00am Thursday Nov 8th, 2007
and in print issue #0645 dated Thursday Nov 8th, 2007

It has been said that water is a renewable resource, but whether that statement is true depends upon the whims of Mother Nature. Weather is not predictable. We can’t assume rain will come; it’s quite possible it may not come. And if rainy weather does arrive, it may not bring enough moisture for all the people now settled in the region as well as future residents expected to occupy the huge number of homes being built.
Many streams in the Sugar Hollow area dried up this year, some for the first time in the more than 20 years I’ve been monitoring them. Even following the recent rains October 24-26 (during which I measured a total of 4.6 inches– a substantial rainfall) some streams remained dry! This is extremely serious because it illustrates how low our water table is.
According to the National Ground Water Association, ground water provides much of any stream’s flow, so they are “windows” on the water table, the ground water that also supplies private wells. Therefore “permanent” streams that have dried up are an irrefutable indication that our groundwater is being depleted, and if streams aren’t being replenished, water withdrawn from reservoirs won’t be replenished either.
It’s quite difficult to replenish ground water. According to the Association, only one quarter of all U.S. rainfall becomes ground water. Thus, when there’s lower-than-normal precipitation, that 25 percent represents a very small quantity of rain available for replenishment. When this goes on for years, the water table simply goes down as people continue to withdraw water from the ground.
Obviously then, residents on wells do not only affect their own source of water but also the amount of water available for stream flow to reservoirs. This is why our current policy of restricting water to those using publicly piped supplies while putting no restrictions on well users is completely nonsensical.
Another problem is that water flow through our clay soils can be quite slow, meaning that the water from rainfall requires time to reach the saturated area below the land surface where ground water collects. Where developers have exposed our landscape by totally removing trees and other vegetation far in advance of construction– think of the old Sperry Marine site for the future Albemarle Place and the Hollymead Town Center on 29N– rainfall hasn’t a chance of making its way downward before evaporating or running off bare ground.
Such open areas “see” an increase in sunlight and dry air, both of which rapidly deplete soils of moisture. Growing a sparse groundcover of grass doesn’t help to slow down evaporation very much. The Association has determined that “46 percent of the U.S. population depends on ground water for its drinking water supply– be it from either a public source or private well.” So denuding of the land should be regulated at the state level because it affects people across municipal borders.
Now consider that some areas acquiesced to the horticultural industry’s arguments to ease drought restrictions– an industry that devotes most of its effort to lawn-growing and maintenance that should not be embraced during drought-stricken times. It’s a disgrace to waste– yes, waste– dwindling supplies of water on a purely unnecessary bit of landscaping. Have you seen anyone lately actually doing anything– other than mowing!– on these large swards of non-native grass?
These properties should instead be growing other kinds of plants that could not only sustain the horticultural industry (in sales and maintenance) but also the wildlife we need to keep our environment working properly.
Meanwhile, proper lawn maintenance is important. Most homeowners and the companies employed to keep grass cut around homes and businesses mow lawns far too short. Extremely short grass can’t shade the soil to slow evaporation, so this increases moisture loss. Warm-season (Bermuda and zoysia) and cool-season (rye, fescue, and bluegrass) grasses should not be cut to less than three inches, especially during the summer. Taller leaf blades mean deeper roots less susceptible to drought and browning. And as most lawn grass in temperate areas can go dormant during drought, it should not be watered.
Local governments should immediately embrace the following actions:
(1) allow people to water only established plants in the ground with water from a rain barrel or other device that catches roof run-off (this could help support the horticultural industry if they sold and installed these systems).
(2) not allow new lawns– in either new construction or older residences– to be put in under drought conditions because they are likely to die anyway after the “establishment” period if there is insufficient rain. (In slope situations, erosion-control blankets can be employed for stabilization and control until sufficient rainfall brings the water table back up to normal levels. At that point, a groundcover (not grass) should be grown; it’s dangerous to mow slopes.)
(3) demand that automatic irrigation systems be shut off until drought conditions end because many of these devices run when it’s totally unnecessary. And it’s not at all unusual to see unregulated sprinklers watering the pavement.
(4) require builders not to clear any more area than necessary when starting construction.
Efficiency– as builders would probably argue– be damned! Desperate situations demand desperate measures.
People cannot afford to behave like the proverbial ostrich with its head in the sand.
Marlene A. Condon (author of The Nature-friendly Garden) managed to take several geology courses while pursuing her degree in physics.