| Lakes in urban or urbanizing areas serve multiple functions and often possess substantial value. Despite their uniqueness, until now they have not been extensively studied.; Heretofore, most attention on the impact of urbanization on waterways has focused on lotic systems (streams). However, the primary focus of this effort is the lentic environment (lakes).; A total of one hundred and thirty-four lakes, ponds and reservoirs are identified within New York City, and a representative subset of nine, are selected for detailed study. All nine are anthropogenically-enhanced to some degree, and are shallow (all but one have maximum depths under 2.5 meters). However, these nine lakes may not be representative of urban and suburban lakes in general because of their shallow depths, their buffering (isolation) by parkland, and the absence of any that are completely natural.; A field sampling program was conducted to assess the sanitary quality and trophic state of the nine lakes, along with the impacts of urban runoff. Data was obtained at each lake during the fall of 1997, the spring of 1998, and the summer of 1998.; Based on the field program and literature search (including unpublished New York State data and reports), three quantitative classification systems are developed and tested. Each of the nine lakes is assigned a score within each system. The three classification systems include Water Input Mechanism, Degree of Artificiality, and Degree of Urbanization. Degree of Urbanization is a measure of the watershed's runoff characteristics, its pollutant export potential, the extent to which the lake is buffered from the impact of urban runoff, and the degree of stream alteration in the drainage area. Statistical analyses are performed to determine whether trophic state and water quality are influenced by proposed classification system scores, and the results indicate little or no influence.; Remedial measures such as dredging, erosion control, diversion of street and highway runoff, and flow augmentation are suggested for the nine detailed study lakes, and future research is recommended. The results of this study, including the proposed classification system, are applied to urban and suburban lakes in New Jersey, California, Georgia, and Florida. |
