12. environmental issues, impacts, mitigations

Environmental Issues, Impacts, and Mitigations of Roads

Gordon Keller, PE, GEGeotechnical Engineergrkeller@fs.fed.usgordonrkeller@gmail.com

A Well Built Minimum Impact Road

• Planning/Environmental Analysis• Location• Design• Construction• Maintenance• Road Closure or Obliteration

GOOD PLANNING +GOOD ENGINEERING

(with conscience)

=GOOD ENVIRONMENTAL

MITIGACION

ENVIRONMENTAL PROTECTION

What are the impacts from roads?

Positive Impacts• Improving quality of life• Better access to schools and clinics• Promoting development of areas• More rapid movement of goods and

services• Lower operating costs• Lower cost of food and products• Everybody wants a road

What are the impacts from roads?

Negative Impacts

• Degradation of water quality• Wildlife mortality and habitat fragmentation• Barriers to fish and AOP movement• Promoting movement of invasive species• Loss of terrain• Land use changes –forests to crops• Pressure on reserves and sensitive areas• Promotion of landslides and stream channel changes• Damage to coastal areas, mangroves, and swamps• High cost of maintenance and repairs• Use of resources• Deforestation and illegal logging/hunting• Pollution and trash• Traffic accidents

CURRENT ISSUES

Water quality degradation

Clean Water Dirty Water

Rolling Dips

• Culverts• Fords and LWX• Bridges

Drainage Crossing Structures

A Fish Barrier

Fish Passage

THE PROBLEM

Fish Baffles

Fish Ladder

http://www.stream.fs.fed.us/fishxing/aop_pdfs.html

http://www.fhwa.dot.gov/engineering/hydraulics/pubs/11008/hif11008.pdf

http://www.fhwa.dot.gov/engineering/hydraulics/pubs/11008/hif11008.pdf

Wildlife Mortality

How big of a problem is mortality, anyway?

• Vehicle-caused wildlife mortality estimated at ONE MILLION vertebrates each day in US

• Deer/vehicle collisions cost BILLIONS of dollars ANNUALLY

• Virtually all wildlife species affected• Hundreds of people killed annually

Huan Xi Township, China

V-Shape

Inverted U-Shape

Better!

Monkey “Overpass”

Lake Jackson-

turtle fence leading into a

culvert

•

Think in

theLong Term

Noxious Weeds/Invasive Species

Kosrae, Micronesia

Roads/Riparian Restoration Team

KNAPWEEDS

BLACK LOCUST

STAR THISTLEMUSK THISTLE PURPLE LOOSESTRIFE

KUDZUTAMARIXLEAFY SPURGEAILANTHUSRUSSIAN

OLIVE

Roads/Riparian Restoration Team

Costos Anuales en Billones de Dolares

$1 Diseases

$1 Mollusks

$37Mammals

$25Microbes

$57 Insects

$34 Plants

$1 Fish $138 Billon por Ano!!

Roads/Riparian Restoration Team

Roads/Riparian Restoration Team

Referencias

2002David Pimentel, Lori Lach, Rodolfo Zuniga, and Doug Morrison.Chapter 16Environmental and Economic Costs Associated with Non-Indigenous Species in the United States

COLONIALIZATION ANDLAND USE CHANGE

LANDSLIDES

COASTAL IMPACTS ON MANGROVES AND REEFS

DEFORESTATION AND ILLEGAL LOGGING

POLLUTION AND TRASH

DUST

TRAFFIC SAFETY AND ACCIDENTS

Road Safety Audits

POOR OR MISSING SIGNS

IMPROVING SIGHT DISTANCE