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OGJ9 Water Quality Standards All streams in the State of Colorado are currently classified as either coldwater or warmwater fisheries for the purpose of establishing water quality standards. These are further subdivided as to the suitability or nonsuitability for primary contact recreation. Basically the only difference in the water quality standards for primary and secondary contact activities concern permissible bacteriological counts. For primary contact activities the present standards are as follows: fecal coliforms, a geometric mean of 200 or less fecal coliform groups per 100 m1 per a minimum of 5 samples within 30 days and no more than 10 percent in excess of 400 groups per 100 m1; total co1iforms, a geometric mean of 1000 or less total coliform groups per 100 ml as above, with no more than 20 percent in excess of 2000 co1iforms per 100 m1; in addition, the fecal streptococcus count will not exceed an average of 20 per 100 m1 based on the mean of 5 samples within 30 days. The State of Colorado is in the process of revlslng its water quality standards. The second draft of the proposed standards was di stri buted for review and comment on December 1, 1977. With respect to primary contact recreation, the standards for total coliforms and fecal streptococcus would be deleted. However, a standard would be established for algae; the currently proposed standard is: "free from objectionable and toxic algae." Although no numerical limitation has been establ ished, the standard would apply to both the species composition and standing crop. In addition to the above changes in standards, the definition of primary contact recreation would be changed to exclude water skiing; therefore, only swimming would be considered a primary contact activity. Bacteriological Study Samples were collected weekly for 8 weeks, between August 22 and October II, 1977, at two sites on the South Platte River in the vicinity of the Narrows Unit by Bureau personnel. One site was located at approximately the inflow point to the reservoir, while the other was located approximately at the damsite. The samples were cultured for total and fecal co1iforms and fecal streptococci at the Northeast Colorado Health Department laboratory in Sterling. The results of the study showed that bacterial levels in the river were highly variable from week to week. Mean values obtained at the Masters (inflow) site and the Narrows (damsite) sites are shown in the following tabulation: 17