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Friday, February 18, 2005

MANAGING THE HUMAN ENVIRONMENT: HILLSIDE MANAGEMENT

MANAGING THE HUMAN ENVIRONMENT: HILLSIDE MANAGEMENT

What is a Mudslide? A hillside shifts sending mud, rocks and trees rumbling down its slope. Homes and property are buried or swept away. People are left homeless, injured or even killed. Worldwide, thousands of people die every year from land and mudslides. In the United Sates alone, land and mudslides cause an estimated [$2 billion] in damage and kill 25 to 50 people every year. [It will be a lot more than that from 2005 onward…] http://www.disasterrelief.org/Disasters/971008landslide/

Mudslides: Mudslides often occur because the natural vegetation has been removed from steep slopes, which, in addition, have rarely been terraced. When there is a lot of rainfall in a short period of time, the soil layer becomes unstable and slides down the sides of mountains. Mudslides are also common along coastal areas… http://www.rocksforkids.com/RFK/Naturaldisasters.html

Solution? Natural Hillside & Landslide Control through Terracing & Vegetation Management:

"We should learn from disaster, the laws of nature cannot be tampered with.” Adi Susmianto, Conservation Director of the Indonesian Ministry of Forestry's regional and Forest Conservation Directorate General, about a mudslide that killed several hundred people, and the solutions to the problem. This solution is as valid in Malibu, California, as it is in Indonesia.


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According to the U.S. Government (FEMA, www.fema.gov/rrr/talkdiz/landslide.shtm ), landslides are a serious geologic hazard common to almost every state in the United States. It is estimated that nationally they cause up to $2 billion in damages and from 25 to 50 deaths annually. Globally, landslides cause billions of dollars in damage and thousands of deaths and injuries each year. Individuals [and communities] can take steps to reduce their personal risk.

Some landslides move slowly and cause damage gradually, whereas others move so rapidly that they can destroy property and take lives suddenly and unexpectedly. Gravity is the force driving landslide movement. Factors that allow the force of gravity to overcome the resistance of earth material to landslide movement include: saturation by water, steepening of slopes by erosion or construction, alternate freezing or thawing, earthquake shaking, and volcanic eruptions.

Climate changes will make landslides more and more common, unless their underlying causes are properly addressed.

The true cause of landslides: Landslides are typically associated with periods of heavy rainfall or rapid snow melt and tend to worsen the effects of flooding that often accompanies these events. In areas burned by forest and brush fires, a lower threshold of precipitation may initiate landslides.

Wildfires can also lead to destructive debris-flow activity. In July 1994, a severe wildfire swept Storm King Mountain, west of Glenwood Springs, Colorado, denuding the slopes of vegetation. Heavy rains on the mountain in September resulted in numerous debris flows…

Here is the main point to understand: Landslides, mudslides, and the like, are not “Acts of God”. 90% of these types of problem have a very human origin. Basically, this is a problem of vegetation, or rather, lack thereof, or lack of optimal vegetation: Entirely a human-created problem.

Consequently, the most efficient way to address these problems and ward them off is proper reforestation and vegetation management. This is particularly true in heavily populated areas. To make it short, except in the case of major earthquakes, landslides are not truly a geological problem, but mainly a manmade environmental problem. Worse, with zoning laws and such, they are often also a governmental problem as well, meaning here that government regulations and activity can be one the causes of the problem, rather than a contributor of solutions. About this, see http://www.mekonginfo.org/mrc_en/announce.nsf/0/4dd7202af007d53247256e67003a44f4?OpenDocument which shows that "However much we would wish to think of these as strictly natural disasters, human activities play a significant role in increasing risk and vulnerability.” As the United Nations themselves say in “The human role in natural disasters” at http://www.undp.org.vn/mlist/envirovlc/032004/post120.htm , “Improved management of ecosystems can save lives”. And not only the lives of some far-away people you might care little about, but your life, the life of your family, the life of your neighbors. To say nothing about loss of property, and potential numerous other inconveniences.

All this means that, in practice, the principal cause of landslides is deforestation and destruction of vegetal cover, usually the consequence of past or present human activity. If human activity is the main cause of landslides, reason compels to consider that reversing the effects of this activity is probably the best way of reversing the unwanted consequence of it: Landslides. Which is, in fact, proves exactly true in the vast majority of cases.

Awareness Information: Areas that are generally prone to landslide hazards include existing old landslides; the bases of steep slopes; the bases of drainage channels; and developed hillsides where leach-field septic systems are used. Areas that are typically considered safe from landslides include areas that have not moved in the past; relatively flat-lying areas away from sudden changes in slope; and areas at the top or along ridges, set back from the tops of slopes.

Learn what to watch for prior to major landsliding. Look for patterns of storm-water drainage on slopes near your home, noting especially the places where runoff water converges, increasing flow over soil-covered slopes. Check hillsides around your home for any signs of land movement, such as small landslides or debris flows or progressively tilting trees.

Landslides occur where they have before, and in identifiable hazard locations. Ask for information on landslides in your area, specific information on areas vulnerable to landslides, and request a professional referral for a very detailed site analysis of your property, and corrective measures you can take, if necessary.

Be aware that your interests might be different from what benefits vested interests and the powers that be: “Evidence is presented to show that there is a growing disparity between the public perception and the scientific evidence relating to the causes of floods and landslides, their impacts and the benefits of mitigation measures. It is suggested that this disparity has arisen through the extensive promotion of certain land uses and engineering interventions by vested interest groups in the absence of any effective dissemination of the scientific evidence, which may allow a contrary view. It is recognized that the interaction of floods and society is a highly complex subject: Floods and landslides may have both natural and anthropogenic causes...” [Quoted from Ian R Calder, Bruce Aylward and Russell A LaFayette - CLUWRR, University of Newcastle upon Tyne, UK & USDA Forest Service, Milwaukee, WI, USA]

How to Protect Your Community and Your Property:
If your property is in a landslide-prone area, contract with a private consulting company specializing in earth movement for opinions and advice on landslide problems and on corrective measures you can take. Such companies would likely be those specializing in geotechnical engineering, structural engineering, or civil engineering. Local officials could possibly advise you as to the best kind of professional to contact in your area. Taking steps without consulting a professional could make your situation worse. However, be aware that “allopathic” remedies, such as lots of concrete, and the like, might be a lot more costly than “oriental medicine” and natural remedies – that is, vegetation.

Install flexible pipefittings to avoid gas or water leaks. Flexible fittings will be less likely to break.

And more than anything else, prepare and execute a plan for reforestation and vegetation management using optimally selected trees and vegetation.

Media and Community Education Ideas:
In an area prone to landslides, publish a special newspaper section with emergency information on landslides and debris flows. Localize the information by including the phone numbers of local emergency services offices, the American Red Cross chapter, and hospitals, as well as publish reliable sources for consulting services, geotechnical engineering and landscaping businesses, vegetation and trees optimally adapted for hillside and landslide management; as well as personal testimony and experiences of people who have addressed the issue successfully.

Report on what city and county governments are doing to reduce the possibility of landslides. Interview local officials about local land- use zoning regulations. Be aware that often, local government is very slow to act, and that their way of addressing problems might be vastly different from what you’d wish them to be. In other words, you might find that zoning laws, city hall and the fire department, for example, are your adversaries, rather than your allies, in your efforts to address the major environmental issue of hillside and landslide management with rational and long-term environmental solutions. Be prepared!

Advocate simple and high impact solutions, and work on putting government back on the right side of the problem: If any environmental group or even any individual was offered use or better, property rights after achieving specified results in a given timeframe, in exchange for proper reforestation and hill management, 90% of all landslides and mudslides would be avoided in less than 10 years time.

Actually, it has been estimated that very simple mitigation measures using terracing, wells and optimally adapted trees and vegetation could alleviate up to 50% of the most common landslide related problem in just 1 to 2 years time! And it’s a lot cheaper than facing the in the medium and long-term unavoidable consequences of doing nothing.

More, proper reforestation and vegetation management creates the opportunity of producing wood, fiber and foodstuff, as well as, possibly, new recreational areas, and can greatly contribute to the local microclimate, air quality, and other such environmental issues.
Show people that there is potentially good money to make by doing the right things, which might encourage everyone to actually do the right thing!

What to Do Before Intense Storms and Long Periods of Rain:
Become familiar with the land around you. Learn whether landslides and debris flows have occurred in your area by contacting local officials, state geological surveys or departments of natural resources, and university departments of geology. Knowing the land can help you assess your risk for danger.

Watch the patterns of storm-water drainage on slopes near your home, and especially the places where runoff water converges, increasing flow over soil-covered slopes. Watch the hillsides around your home for any signs of land movement, such as small landslides or debris flows, or progressively tilting trees. Watching small changes could alert you to the potential of a greater landslide threat.

Remember that one ounce of prevention can often help you avoid many pounds if not tons of cure. Learn to “sculpt the land” before hand. Small work beforehand can redirected channels, or diffuse problems, that otherwise could have become acute. Also, issues such as water saturation, water tables, etc, can often be addressed beforehand with natural water-pumps, also known as “trees”. Select cultivars and clones of optimally adapted and relatively fire-resistant trees can grow up to 20 feet a year, reach 80 feet in 6 or 7 years, and have taproots going up to150% deeper than they are tall. Some of these trees can be planted only a few feet apart, and in dense patterns that practically make a mudslide impossible under normal conditions.

What to Do After a Landslide:
Replant damaged ground with fast-growing species as soon as possible since erosion caused by loss of ground cover can lead to flash flooding and mudslides. [Quoted verbatim from federal guidelines.] And, of course, terrace your hills!

Seek the advice of geotechnical and vegetation management experts for evaluating landslide hazards or designing corrective techniques to reduce landslide risk. A professional will be able to advise you of the best ways to prevent or reduce landslide risk, without creating further hazard.

You can find more about what to do about landslides in general here: http://www.prepare.org/text/basic/mudTX.htm . This document was prepared by the National Disaster Education Coalition with contributions of the American Red Cross, Federal Emergency Management Agency, International Association of Emergency Managers, Institute for Business and Home Safety, National Fire Protection Association, National Weather Service, United States Department of Agriculture/Cooperative State Research, Education and Extension Service and United States Geological Survey. The present document was prepared in part using material found there, and in part with material provided by the Foundation for Naturally Optimal Solutions to Environmental Problems with Regenerative Agriculture & Sylviculture and the Sustainable Organic Regenerative Agriculture & Sylviculture Trust. © 2005 NOSEPRAS Foundation & SORAS Trust. All rights reserved worldwide.

1 Comments:

At March 19, 2008 at 11:52 AM, Blogger Paz said...

People should learn more about energy alternatives like electric cars. The new ones coming out are way better than gas cars. One of the main electric car companies, Zap, has delivered more than 100,000 electric vehicles (source: www.zapworld.com). EV’s cost 1 to 3 cents per mile to run, compare that to regular cars!

 

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