Revision History for SIR 2014-5127 D. Matthew Ely, Eric R. Burns, David S. Morgan, John J. Vaccaro Numerical Simulation of Groundwater Flow in the Columbia Plateau Regional Aquifer System, Idaho, Oregon, and Washington ----------------------------------------------------- Posted online August 19, 2014 ----------------------------------------------------- Revised and reposted January 15, 2015 The text version was modified. Page 1: Two sentences in the 5th paragraph were changed from "For the mean transient model, the mean and median difference between simulated and measured hydraulic heads is -14 and -1 ft, respecitvely, with a standard deviation of 167 ft over a 5,658 ft range of measured heads. The residuals for the simulation period show that 50 percent of the simulated heads exceeded measured heads with a median residual value of 35 ft, and 50 percent were less than measured heads with a median residual value of -75 ft." to "For the transient model, the mean and median difference between simulated and measured hydraulic heads is -10 and 4 ft, respectively, with a standard deviation of 164 ft over a 5,648 ft range of measured heads. The residuals for the simulation period show that 52 percent of the simulated heads exceeded measured heads with a median residual value of 43 ft, and 48 percent were less than measured heads with a median residual value of -76 ft." Page 10: Text in the 3rd paragraph was changed from "Mean annual recharge from irrigation return flow in the study area was 4.2 million acre-ft (1985–2007) with 2.1 million acre-ft (50 percent) occurring within the predominately surface-water irrigated regions of the Yakima Basin, Umatilla Basin, and Columbia Basin Irrigation Project." to "Mean annual recharge from irrigation return flow in the study area was 4.2 million acre-ft (1985–2007) with 2.1 million acre-ft (50 percent) occurring within the predominately surface-water irrigated regions of the Yakima and Umatilla River Basins and Columbia Basin Irrigation Project." Page 28: Text in the 2nd paragraph was changed from "Pumpage estimates using this method were compared to independent estimates for the Umatilla Basin (Kahle and others, 2011, fig. 21B), the Odessa subarea in east-central Washington (Cline, 1984), and the area of the Yakima River Basin that intersects the CPRAS model domain (Ely and others, 2011)." to "Pumpage estimates using this method were compared to independent estimates for the Umatilla River Basin (Kahle and others, 2011, fig. 21B), the Odessa subarea in east-central Washington (Cline, 1984), and the area of the Yakima River Basin that intersects the CPRAS model domain (Ely and others, 2011)." Page 32: Text in the 5th and 6th paragraphs were changed paragraph 5: from "Irrigation projects exist throughout much of the Columbia Plateau, but the largest areas of intense irrigation are in the Yakima, Walla Walla, and Umatilla River Basins, and Columbia Basin Irrigation Project (fig. 2)." to "Irrigation projects exist throughout much of the Columbia Plateau, but the largest areas of intense irrigation are in the Yakima and Walla Walla River Basins, Umatilla subarea, and Columbia Basin Irrigation Project (fig. 2)." paragraph 6: from "(1) CBIP irrigation was assumed to start in 1948 with irrigation increasing linearly to 100 percent in 1955" to "(1) CBIP irrigation was assumed to start in 1950 with irrigation increasing linearly to 100 percent in 1953" from "(3) Umatilla River Basin surface-water irrigation was assumed to be 24 percent at the start of the transient simulation (1900), increasing linearly to 34 percent in 1961, to 75 percent in 1975, and to 100 percent by 1984 (M. Ladd, Oregon Water Resources Department, written commun., 2012). Surface-water irrigation outside of the large projects in the Yakima and Umatilla River Basins and the CBIP are a relatively small fraction of total surface-water irrigation..." to "(3) Umatilla subarea surface-water irrigation was assumed to be 24 percent at the start of the transient simulation (1900), increasing linearly to 34 percent in 1961, to 75 percent in 1975, and to 100 percent by 1984 (M. Ladd, Oregon Water Resources Department, written commun., 2012). Surface-water irrigation outside of the large projects in the Yakima River Basin, Umatilla subarea, and the CBIP are a relatively small fraction of total surface-water irrigation..." Page 33: Text in the 1st paragraph was changed from "By 2007, recharge associated with surface-water irrigation was estimated as 0.61 million acre-ft/yr and recharge associated with groundwater irrigation was estimated as 0.45 million acre-ft/yr, indicating that on average, approximately 19 percent more water was entering the aquifer system during 2000-2007 (fig. 14B), than during the predevelopment period." to "By 2007, recharge associated with surface-water irrigation was estimated as 1.0 million acre-ft/yr and recharge associated with groundwater irrigation was estimated as 0.61 million acre-ft/yr. During model calibration, surface-water irrigation efficiency was increased from 50 to 75 percent, similar to assumed groundwater irrigation efficiency. This adjustment reduced recharge due to surface-water irrigation over time. Approximately 21 percent more recharge was entering the aquifer system during 2000-2007 (fig. 14B), than during the predevelopment period." Page 56: Text in the 1st, 3rd, and 4th paragraphs was changed paragraph 1: from "For 46,460 water-level measurement points, the mean and median difference between simulated minus measured hydraulic heads is -14 and -1 ft, respectively." to "For 46,460 water-level measurement points, the mean and median difference between simulated minus measured hydraulic heads is -10 and 4 ft, respectively." from "The residuals for the transient simulation period show that 50 percent of the simulated heads exceeded measured heads with a median residual value of 35 ft, and 50 percent were less than measured heads with a median residual value of -75 ft." to "The residuals for the transient simulation period show that 52 percent of the simulated heads exceeded measured heads with a median residual value of 43 ft, and 48 percent were less than measured heads with a median residual value of -76 ft." from "The weighted measurements compared with weighted simulated values generally are along a straight line with a slope of 1.02 and a y-intercept of 2.0 ft." to "The weighted measurements compared with weighted simulated values generally are along a straight line with a slope of 1.03 and a y-intercept of -18.0 ft." paragraph 3: from "For example, 74 percent of simulated heads in the GWMA were less than measured heads, in 193 instances at 27 locations, by greater than 500 ft." to "For example, 67 percent of simulated heads in the GWMA were less than measured heads, in 187 instances at 24 locations, by greater than 500 ft." paragraph 4: from "Simulated heads generally were larger than measured heads in the Yakima and Umatilla River Basins, 71 and 63 percent of the time, respectively. There also was a bias toward residuals of greater than 500 ft in areas of the Yakima and Umatilla River Basins." to "Simulated heads generally were larger than measured heads in the Yakima River Basin and Umatilla subarea, 63 and 67 percent of the time, respectively. There also was a bias toward residuals of greater than 500 ft in areas of the Yakima River Basin and Umatilla subarea." paragraph 5: from "The pattern of underpredication in the GWMA and overprediction in the Yakima and Umatilla River Basins was somewhat expected... The Umatilla and Yakima River Basins have areas of upward gradients..." to "The pattern of underprediction in the GWMA and overprediction in the Yakima River Basin and Umatilla subarea was somewhat expected... The Yakima River Basin and Umatilla subarea have areas of upward gradients..." paragraph 7: from "Another way to assess the ability of the CPRAS model to represent groundwater flow and trends is to examine the vertical distribution of hydraulic heads in the Umatilla and Palouse Slope well groups identified in Burns and others (2012b)." to "Another way to assess the ability of the CPRAS model to represent groundwater flow and trends is to examine the vertical distribution of hydraulic heads in the Umatilla subarea and Palouse Slope well groups identified in Burns and others (2012b)." Page 62: The 2nd paragraph of was deleted. paragraph 3: "Umatilla River Basin" (two instances) was changed to "Umatilla subarea" Page 80: Text in the 1st paragraph was changed from "Groundwater recharge ranged from about 5.6 million acre-ft in 2001 to 10.3 million acre-ft in 1997, a factor of nearly two. For the average year (2000), recharge was within 6 percent of the mean annual recharge for 1950-2007. For the wet year (1997), outflows to storage greatly exceeded inflows from storage, resulting in an increase of groundwater in storage of 1.6 million acre-ft." to "Groundwater recharge ranged from about 6.2 million acre-ft in 2001 to 10.9 million acre-ft in 1997, an increase of about 76 percent. For the average year (2000), recharge was within 2 percent of the mean annual recharge for 1950–2007. For the wet year (1997), outflows to storage greatly exceeded inflows from storage, resulting in an increase of groundwater in storage of 1.5 million acre-ft." Page 85: Text in the 4th paragraph of the Summary was changed from "For the transient model, the mean and median difference between simulated minus measured hydraulic heads is -14 and -1 ft, respectively, with a standard deviation of 167 ft over a 5,648 ft range of measured heads. The residuals for the simulation period show that 50 percent of the simulated heads exceeded measured heads with a median residual value of 35 ft, and 50 percent were less than measured heads with a median residual value of -75 ft." to "For the transient model, the mean and median difference between simulated minus measured hydraulic heads is -10 and 4 ft, respectively, with a standard deviation of 164 ft over a 5,648 ft range of measured heads. The residuals for the simulation period show that 52 percent of the simulated heads exceeded measured heads with a median residual value of 43 ft, and 48 percent were less than measured heads with a median residual value of -76 ft." Modified figures: Figure 2: Explanation was changed from "Umatilla River Basin" to "Umatilla Subarea." Figure caption was revised. Figure 4: Well symbol was added to explanation. Figures 7-8, 13, and 18: Labeling of the Walla Walla River was corrected. Figure 9: Data were revised for horizontal-flow barriers 1, 10, 21, 53, 54, and 68. Labeling of the Walla Walla River was corrected. Figure 14: (A) Labeling of the Walla Walla River was corrected. (B) Groundwater recharge data were revised. Figure 19: (A) Horizontal flow-barrier data were removed. Labeling of the Walla Walla River was corrected. (B) Horizontal-flow barrier data were revised. Labeling of the Walla Walla River was corrected. Figure 20: Caption was revised: "from the steady-state model" was added after "(simulated minus measured)" Figure 21: Unweighted and weighted hydraulic-head residual data were revised. Figure 22: Simulated drawdown and unweighted residual data were revised. Figure 23: Measured and simulated hydraulic head data were revised. Figure 24: Simulated and measured residual data were revised. Explanation was changed from "Umatilla River Basin" to "Umatilla Subarea" Figure 25: Explanation was changed from "Umatilla Basin" to "Umatilla Subarea" and caption was changed from "...Umatilla River Basin..." to "...Umatilla subarea..." Figures 26A and 26B: Simulated water-level data were revised. Caption: "Umatilla Basin" was changed to "Umatilla subarea" and the last sentence was changed from "The lines under each data series show corresponding transient simulated water levels from layers intersected by nearby potentially commingling wells." to "The numbered lines corresponding to each data series show transient simulated water levels from layers intersected by nearby potentially commingling wells." Figures 28A-28D: Simulated water-level altitude data were revised. Figure 29: Simulated base-flow data were revised. Labeling of the Walla Walla River was corrected. Figures 30A-30D: Simulated composite hydraulic head data were revised. Labeling of the Walla Walla River was corrected. Figures 31A-31D: Simulated composite drawdown data were revised. Labeling of the Walla Walla River was corrected. Figure 32: Simulated annual water-budget flux data for predevelopment to 2007 were revised. Figure 33: Simulated annual water-budget flux data for wet (1997), average (2000), and dry (2001) years were revised. Figures 34A-34C: Simulated drawdown data were revised. Modified tables: Table 4: Horizontal and vertical hydraulic conductivity parameter values were revised for the Overburden unit. Drain conductance multiplier values were revised. Table 5: Simulated base-flow data were revised for sites 2, 4-7, 9, 11, 13-44, 46-49; Error data were revised for sites 5, 6, 19, 22, 24, 27, 30-31, 46.