Scientific Investigations Report 2009–5030
U.S. GEOLOGICAL SURVEY
Scientific Investigations Report 2009–5030
Table 2. Composition of surface flow-system components during the irrigation season in the DR2 catchment, Yakima River basin, Washington.
[Catchment surface-water outflow: median concentrations measured in DR2 (site W13) from mid-June through mid-September 2004. Base flow: median concentrations measured in DR2 site (W13) from mid-October 2003 through mid-March 2004. Canal: median concentrations measured in Sunnyside Canal (site W15) from mid-June through mid-September 2004. Field drain: median concentrations measured in the field drain (site W42) from mid-June through mid-September 2004. SAF: hypothetical SAF calculated using equation 3. Abbreviations: SAF, seasonal agricultural flow; SiO2, silicon dioxide; m3/s, cubic meter per second; μS/cm, microsiemen per centimeter; mg/L, milligram per liter; na, not applicable]
Units | Catchment surface-water outflow |
Base flow | Canal | Field drain | SAF | |
---|---|---|---|---|---|---|
Discharge | m3/s | 0.204 | 10.068 | na | na | 0.136 |
Specific conductance | µS/cm | 434 | 657 | 104 | 212 | 321 |
Nitrate | mg/L as N | 3.3 | 5.4 | 0.22 | 2.4 | 2.3 |
SRP | mg/L as P | 0.18 | 0.092 | 0.029 | 0.10 | 0.22 |
Calcium | mg/L | 41 | 64 | 11 | 20 | 29 |
Magnesium | mg/L | 14 | 25 | 4.2 | 5.9 | 9.2 |
Potassium | mg/L | 5.4 | 6.7 | 1.1 | 3.3 | 4.7 |
Sodium | mg/L | 25 | 41 | 4.7 | 12 | 17 |
Chloride | mg/L | 11 | 17 | 2.1 | 3.4 | 7.1 |
Sulfate | mg/L | 34 | 68 | 3.1 | 7.6 | 17 |
Silica | mg/L as SiO2 | 30 | 46 | 14 | 19 | 22 |
1 Median discharge measured in DR2 (site W13) from mid-October 2003 through mid-March 2004, adjusted by the ratio of nonirrigation-to-irrigation season hydraulic gradient from ground water to surface water.