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0134 Exceedances of the State water-quality standards can be observed in the summaries listed in tables 4 througb 12. Median pH values at all stations were always within the water-quality-standard allowance range. The maximum water-quality standard for pH was exceeded once at station 07103780 Monument Creek at USAFA (table 5) in August 1985 and once at station 07105530 Fountain Creek below CSWWTP (table 10) in September 1984. Median dissolved-oxygen concentrations always exceeded the water-quality standard. At station 07105905 Fountain Creek below Fountain (table 11) in July 1988 and at station 07106500 Fountain Creek at Pueblo (table 12) in August 1981, the dissolved-oxygen concentrations did not meet the water- quality standard. At station 07103700 Fountain Creek near Colorado Springs (table 8) in August 1980, the dissolved-oxygen concentrations did not meet the standard for spawning of cold-water fish. At station 07106500 Fountain Creek at Pueblo (table 12), the standard for nitrite plus nitrate as nitrogen was exceeded once in July 1982. Median con- centrations of total phosphorus were larger than 0.1 mg/L except at station 07103747 Monument Creek at Palmer Lake (table 4) and 07103700 Fountain Creek near Colorado Springs (table 8). Data for total phosphorus were not collected at station 07103780 Monument Creek at USAFA. For the stations with median values larger than 0.1 mg/L, the median concentrations ranged from 0.16 mg/L at station 07104000 Monument Creek at Pikeview (table 6) to 4.4 mg/L at station 07105530 Fountain Creek below CSWWTP (table 10). There is no State water-quality standard or Federal criterion for phosphorus; however, the U.S. Environmental Protection Agency (1986) has stated that in order to prevent nuisance algal growth associated with accelerated eutrophication, total phosphorus concentrations should not exceed 0.1 mg/L in streams. This con- centration is associated with eutrophication-related water-quality problems in reservoirs. Currently (1988), there are off-stream but no on-stream reservoirs on these two creeks. Median trace-metal concentrations were less than the State standards at all the stations except the following: stations 07103780 Monument Creek at USAFA (table 5) and 07105905 Fountain Creek below Fountain (table 11), dis- solved manganese; stations 07104000 Monument Creek at Pikeview (table 6) and 07104905 Monument Creek at Bijou (table 7), total recoverable copper; and station 07106500 Fountain Creek at Pueblo (table 12), total selenium. The State water-quality standard for fecal coliform was exceeded at least once at each station except stations 07103747 Monument Creek at Palmer Lake (table 4) and 07103780 Monument Creek at USAFA (table 5). WATER-QUALITY VARIATIONS AND TREND ANALYSIS Variations and trends in water-quality properties and constituents were investigated during this study. Water-quality variations among stations were evaluated qualitatively using box plots. Variability of water-quality data at each station and among stations was compared for the period of record. Because the period of record is not the same for all stations, the statistical determination of water-quality trends among seven of the nine stations was done for a common period of record: water years 1980 through 1988. Time- series trends at all nine stations were determined for the period of record. 7