Geographic aspects of the urban hydrology of Knoxville, Tennessee

The study includes three different approaches:

(1) Descriptive analysis of the Knoxville area and the urban drainage basins (Chapter III). This descriptive analysis synthesizes qualitatively the discharge characteristics of each basin and identifies the significant factors affecting the local basin hydrology and locates possible inter-basin water transfer paths.

(2) Review of detailed studies of the Knoxville urban hydrology and discussion of flood problems (Chapter IV). The chapter reviews the TVA small basin study and its hydrologic models and establishes quantitative estimates of the effects of urbanization and loss or gain through the groundwater system. Because flooding has been frequent in Knoxville, problems of flooding, especially those related to sinkholes and increase of impervious surfaces are emphasized.

(3) Estimation of basins' discharge through a water balance approach. A modified Thornthwaite water balance model is used to simulate the annual and seasonal allocations of precipitation for surplus and to approximate basin and area-wide runoff. Comparison of runoff estimates under urban and rural conditions also permits evaluation of the role of urbanization upon stream discharge.

These three approaches draw similar conclusions and supplement each other with explanations. All indicate that geology and urban land use (impervious surfaces) are the two most significant characteristics locally affecting the Knoxville urban hydrologic system. The study offers an explanation for the peculiar water behavior pattern (interbasin water transfer) and suggests where these phenomena are most likely to occur. A possibility of inter-basin water transfer between First Creek and Second Creek basins occurs in the vicinity of Inskip, Dutch Valley Road, I-640, and Woodland Avenue. Between Second Creek and Third Creek basins transfer occurs in the vicinity of Merchant Drive and Clinton Highway. Between Third Creek and Fourth Creek basins transfers occurs near David Bell Church east of Amherst Road on Middlebrook Pike and between Papermill Road and Sutherland Avenue. Between Fourth Creek and Ten Mile Creek basins transfer occurs near Gleason Drive, west of Deane Hill Drive and southwest of Middlebrook Pike. Among the studied basins, Third Creek is a "normal" basin with no significant bypass losses. First Creek, Fourth Creek, and possibly Second Creek basins encounter some water losses through sinkholes and solution channels. From water budget estimates, Ten Mile Creek basin appears to import water from Fourth Creek and probably, indirectly, from First Creek and Second Creek.