Decadal and Shorter Period Variability of Surf Zone Water Quality at Huntington Beach, California

• Published in: Environmental science & technology Vol. 36; no. 18; pp. 3885 - 3892
• Main Authors: Boehm, A. B, Grant, S. B, Kim, J. H, Mowbray, S. L, McGee, C. D, Clark, C. D, Foley, D. M, Wellman, D. E
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.09.2002
• Subjects: Applied sciences; Bacteria; California; Coasts; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Enterobacteriaceae - isolation & purification; Environmental Monitoring - methods; Exact sciences and technology; Humans; Longitudinal Studies; Natural water pollution; Oceans; Pollution; Pollution, environment geology; Seasons; Seawater; Seawaters, estuaries; Sewage - microbiology; USA, California, Huntington Beach; Water Microbiology; Water Movements; Water Pollutants - analysis; Water pollution; Water quality; Water treatment and pollution; Pacific Ocean; California; United States; North America; America; Huntington Beach California; United States > US; INE, USA, California, Huntington Beach; Short term; Microbiology; Coliforms; Time variation; Biological monitoring; Coastal zone; Recreational activity; Tide effect; Quality assurance; Seasonal variation; Pathogenic; Water quality; Water pollution; Feces; Sampling; Surf zone; Biological contamination; Seawater
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es020524u

The concentration of fecal indicator bacteria in the surf zone at Huntington Beach, CA, varies over time scales that span at least 7 orders of magnitude, from minutes to decades. Sources of this variability include historical changes in the treatment and disposal of wastewater and dry weather runoff, El Niño events, seasonal variations in rainfall, spring-neap tidal cycles, sunlight-induced mortality of bacteria, and nearshore mixing. On average, total coliform concentrations have decreased over the past 43 years, although point sources of shoreline contamination (storm drains, river outlets, and submarine outfalls) continue to cause transiently poor water quality. These transient point sources typically persist for 5−8 yr and are modulated by the phase of the moon, reflecting the influence of tides on the sourcing and transport of pollutants in the coastal ocean. Indicator bacteria are very sensitive to sunlight; therefore, the time of day when samples are collected can influence the outcome of water quality testing. These results demonstrate that coastal water quality is forced by a complex combination of local and external processes and raise questions about the efficacy of existing marine bathing water monitoring and reporting programs.