WATER QUALITY IMPACTS OF FOREST FIRES

Abstract

This paper is concerned with the effects of forest fires on water quality, especially surface water quantity. The topic is important since surface water constitutes the main source of water for most domestic, industrial and commercial uses in the United States. The bulk of the surface water is the product of runoff from precipitation that falls as snow or rain on our forested and rangeland watersheds. In many areas such as the arid and semi-arid Southwest, the vegetation in these watersheds is dry and susceptible to wildfires. Oftentimes, fire in the form of prescribed burning is used to protect these areas from wildfire. However, such fire suppressions have resulted in overcrowded and dense vegetation and the production of abundant fuels in watersheds. Such a situation and the frequently recurring drought and extensive insect infestation have most forest systems susceptible to catastrophic fires that scorched many of the Nation's forests, rangelands, parks and other large-scale real estate properties (Neary et al. 2008, Lutz et al. 2009, Stein et al. 2013). In 2013, there were a total of 9,230 lightening started fires in the United States burning 3,057,566 acres. In the same year, there were 38,349 humancaused fires that burned 1,261,980 acres. This made the total acreage burned by the two types of fires in 2013 to be 4,319,546 acres (National Interagency Fire Center 2014). Such fires accounted for $13.7 billion in total economic losses and $7.9 billion in insured losses from 2000 through 2011 in the United States (Haldane 2013, International Association of Wildland Fire 2013). These burns also have tremendous effects on the characteristics of water-producing watersheds and the quality of the water coming out of them. This paper discusses the effects of wildland fires on water quality and suggests ways of managing fire-prone forested water source areas to prevent their degradation from wildland fires. The paper uses information from recently occurred catastrophic fires in Arizona to demonstrate the effects of wildland fires on water quality.