USGS Home
Contact USGS
Search USGS

U.S. GEOLOGICAL SURVEY
Data Series 338

Level 1 Water-Quality Inventory of Baseline Levels of Pesticides in Urban Creeks—Golden Gate National Recreation Area and the Presidio of San Francisco, California

Prepared in cooperation with the National Park Service

By Michelle L. Hladik and James L. Orlando

Abstract

To characterize baseline water-quality levels of pesticides in Golden Gate National Recreation Area and the Presidio of San Francisco, the U.S. Geological Survey collected and analyzed surface-water and bed-sediment samples at 10 creeks during February, April, and July 2006. Pesticide data were obtained using previously developed methods. Samples from sites in the Presidio were analyzed only for pyrethroid insecticides, whereas the remaining samples were analyzed for pyrethroids and additional current and historical-use pesticides. Pesticide concentrations were low in both the water (below 30 ng/L) and sediment (below 3 ng/g). The pyrethroid bifenthrin was detected in water samples from two sites at concentrations below 2 ng/L. Other compounds detected in water included the herbicides dacthal (DCPA) and prometryn, the insecticide fipronil, the insecticide degradates p,p'-DDE and fipronil sulfone, and the fungicides cyproconazole, myclobutanil and tetraconazole. The only pesticides detected in the sediment samples were p,p'-DDT and its degradates (p,p'-DDD and p,p'-DDE). Pesticide information from the samples collected can provide a reference point for future sampling and can help National Park Service managers assess the water quality of the urban creeks.

Contents

Abstract
Introduction
Study Design and Methodology
Results
References Cited

This report is available online in Portable Document Format (PDF). If you do not have the Adobe Acrobat PDF Reader, it is available for free download from Adobe Systems Incorporated.

Download the report (PDF, 1.25 MB)

Document Accessibility: Adobe Systems Incorporated has information about PDFs and the visually impaired. This information provides tools to help make PDF files accessible. These tools convert Adobe PDF documents into HTML or ASCII text, which then can be read by a number of common screen-reading programs that synthesize text as audible speech. In addition, an accessible version of Adobe Reader 8.0 for Windows (English only), which contains support for screen readers, is available. These tools and the accessible reader may be obtained free from Adobe at Adobe Access.

Send questions or comments about this report to the author, Michelle Hladik, (916) 278-3183.

For more information about USGS activities in California, visit the USGS California Water Science Center home page.