Chapter 12 – Human Impact on the Simi Valley Environment

Without modern technology, Simi Valley’s environment was capable of supporting only a small handful of people. Today, more than 125,000 people are sustained in the arid valley by a constant stream of consumables shipped in from other parts of the state and country. This has resulted in significant impacts on the local environment.

Earth

I remember going to the Simi Valley Landfill with my dad when I was a child. At the time, the landfill was situated at the bottom of a deep canyon in the hills southwest of the city. Today that canyon is a mountain of buried solid waste.

Simi Valley Landfill.

The 297 acre Simi Valley Landfill is permitted to accept 3000 tons of solid waste and 6000 tons of recyclable materials each and every day. The landfill handles 60% of Ventura County’s waste disposal needs. Approximately 25% of the materials brought in are recycled.

Simi Valley Landfill

Air

This time of year, Simi Valley enjoys relatively clean air; not so a few months from now. Maximum daily one-hour ozone measurements routinely exceed state standards from the middle of June through July, and occasionally surpass less stringent federal standards.

2006 California Air Resources Board Data

It would seem logical to think that air quality diminishes with population growth, but because of California’s tough air quality laws, the opposite has actually occurred. The number of days during which Ventura County has exceeded federal and state one-hour and eight-hour ozone standards has followed a downward trend since the early 1990’s.

Countywide Days Exceeding State and Federal Ozone Standards

Fire

Rocketdyne Propulsion and Power Corporation built the engines that sent the USA to the moon. In the late 1950’s, Rocketdyne’s Santa Susana Field Laboratory—located in the hills south of Simi Valley—also operated the first experimental commercial nuclear power plant which delivered electricity to over a thousand homes in the nearby town of Moorpark. On July 12, 1959, it also became the sight of the world’s first reactor core meltdown. Radiation released pursuant to the meltdown is believed to have been 260 to 459 times greater than that released during the Three Mile Island disaster.

At the time of the meltdown, the area surrounding Rocketdyne was sparsely populated. Today, over 150,000 people live within five miles of the site and at least a half million live within ten miles of the site. The site was never properly cleaned up despite plans to sell much of it for residential development. Last October, an agreement was reached between Governor Schwarzenegger and Boeing (the current owner) to turn 2,400 acres of the site into a state park.

View of Rocketdyne Facility Atop Hills South of Simi Valley

Rocketdyne Santa Susana Field Laboratory

Water

Simi Valley run off water eventually all ends up in the Arroyo Simi flood control channel which follows the bed of the natural arroyo at the base of the Simi Hills (an arroyo is a seasonal waterway in the winter and a dry wash at other times of year). The water that makes it to the arroyo is laden with nutrients from fertilizers from lawns, parks, and golf courses, so wherever there is an abundance of water in the arroyo, signs of eutrophication are present.

Arroyo Simi

Simi Valley only receives an average of 14 inches of rain per year and most of that falls from December through February. The only way that life can be sustained in this type of climate is by importing water from far-away sources like the Colorado River to the east and the Feather River to the north. Ventura County’s Calleguas Municipal Water District purchases most of the water used by Simi Valley from the Metropolitan Water District which serves nearly all of coastal Southern California.

Sources of Water to the Calleguas Municipal Water District

Sources:

“Calleguas MWD – District Profile” Calleguas Municipal Water District. 2006 April 20, 2008 http://www.calleguas.com/profile.htm

“Maximum Daily Ozone Measurements.” California Air Resources Board. April 20, 2008 http://www.arb.ca.gov/adam/cgi-bin/db2www/adamweeklyc.d2w/branch

“Santa Susana Field Laboratory.” Wikipedia. 17 Feb 2008. April 20, 2008 http://en.wikipedia.org/wiki/Santa_Susana_Field_Laboratory

“VCAPCD – Air Quality.” Ventura County Air Pollution Control District. April 20, 2008 http://www.vcapcd.org/air_quality.htm