FECAL‐INDICATOR BACTERIA IN STREAMS ALONG A GRADIENT OF RESIDENTIAL DEVELOPMENT1

ABSTRACT: Fecal‐indicator bacteria were sampled at 14 stream sites in Anchorage, Alaska, USA, as part of a study to determine the effects of urbanization on water quality. Population density in the subbasins sampled ranged from zero to 1,750 persons per square kilometer. Higher concentrations of fecal‐coliform, E. coli, and enterococci bacteria were measured at the most urbanized sites. Although fecal‐indicator bacteria concentrations were higher in summer than in winter, seasonal differences in bacteria concentrations generally were not significant. Areas served by sewer systems had significantly higher fecal‐indicator bacteria concentrations than did areas served by septic systems. The areas served by sewer systems also had storm drains that discharged directly to the streams, whereas storm sewers were not present in the areas served by septic systems. Fecal‐indicator bacteria concentrations were highly variable over a two‐day period of stable streamflow, which may have implications for testing of compliance to water‐quality standards.     

INSTITUTIONAL ANALYSIS CRITERIA FOR WATER SUPPLY PLANNING1

ABSTRACT: This paper discusses the selection and use of criteria for an institutional analysis of municipal water supply conducted in anchorage, Alaska. Although not universally acepted or used. evaluation criteria for most technical fields have been established either formally or informally. Cost-benefit rtios, cost-effectiveness, and environmental impacts are examples of technical evaluation criteria that can be quantified relatively easily (although poorly in some cases). The field of institutional analysis has evaluative criteria that are much less readily defined than those of technical fields, in part because many of the criteria are not quantifiable and in part because the area of the study is new.