scenario. In the SC STA scenario, STA 3/4 inflows were first routed through the single

compartment reservoir (Figure 4-4), and therefore the inflow concentration is equal to the

EAASR outflow concentration. The results of the above scenarios are presented for the

EAASR and STA 3/4 in Tables 5-1 and 5-2, respectively.

Table 5-1. Single Compartment EAASR Results for Total Phosphorus with Variable
 Depths
 Area Inflow Depth HRT Cin Cout Percent
 Scenario (acres) (ac-ft/d) (ft) (days) (mg/L) (mg/L) Removal
 SC base 30,720 1,686 5.9 108 0.105 0.040 62%
 SC base @ 9 ft. 30,720 1,686 9.0 164 0.105 0.031 70%
 SC base @ 12 ft. 30,720 1,686 12.0 219 0.105 0.028 74%
 SC STA 30,720 2,705 5.9 67 0.101 0.051 49%
 SC STA @ 9 ft. 30,720 2,705 9.0 102 0.101 0.040 60%
 SC STA @ 12 ft. 30,720 2,705 12.0 136 0.101 0.034 66%

 Table 5-2. STA 3/4 Results for the Single Compartment EAASR for Total Phosphorus
 with Variable Depths
 Area Inflow Depth HRT Cin Cout Percent
 Scenario (acres) (ac-ft/d) (ft) (days) (mg/L) (mg/L) Removal
 SC base 17,920 2,201 2.4 29 0.066 0.021 69%
 SC base @ 9 ft. 17,920 2,201 2.4 29 0.061 0.020 67%
 SC base @ 12 ft. 17,920 2,201 2.4 29 0.060 0.020 66%
 SC STA 17,920 2,201 2.4 29 0.051 0.020 61%
 SC STA @ 9 ft. 17,920 2,201 2.4 29 0.040 0.020 50%
 SC STA @ 12 ft. 17,920 2,201 2.4 29 0.034 0.020 42%

 The results of varying the depth show that it may be possible to improve the

quality of the EAASR outflow by increasing the mean depth beyond 5.9 feet. The

EAASR has a maximum depth of 12 feet. If it could be kept full, then the HRT increases

from 108 days to 219 days resulting in a significant improvement in water quality.

However, it is unlikely that the EAASR could be operated full since this would conflict

with other purposes such as flood control and water supply. An intermediate increase in

depth to 9 feet also shows good improvement in water quality and would be more

feasible to attain.