ILLINOIS WATER AND CLIMATE SUMMARY November 2008

Illinois State Water Survey

2204 Griffith Drive, Champaign, IL 61820 • Tel (217) 333-2210 • Fax (217) 333-6540

November 2008 Overview (Bob Scott) Temperatures in Illinois during November were below average and precipitation was below average. Soil moisture within the top 40 inches of soil was below the long-term statewide average. Mean streamflows were above median heights. Shallow groundwater levels remained above long-term average depths. Temperatures across Illinois (Figure 1) for November were below average (a -1.3-degree departure). Crop Reporting District (CRD) temperatures ranged from 0.1 degrees above average (northwest) to 2.7 degrees below average (southeast). Precipitation amounts for Illinois in November were below average (Figure 1). The statewide average of 1.51 inches represented a 1.81-inch deficit or 46 percent of average for the month. The west CRD received the least amount of rainfall, 1.03 inches (36 percent of average), while the southeast CRD recorded the greatest rainfall total with 2.76 inches (64 percent of average). Soil moisture conditions in the 0- to 40-inch (0- to 100-centimeter) layer in Illinois at the end of November generally ranged from slightly above normal to slightly below normal in all layers (Figure 1). Mean provisional streamflow statewide was above the median flow in November, 170 percent of median (Figure 1). Rivers throughout Illinois recorded monthly mean discharges in the normal to above normal range. Water surface levels at the end of November were below the normal pool/target operating level at 17 of 33 reporting reservoirs. At the end of November, Lake Shelbyville, Carlyle Lake, and Rend Lake were approximately at seasonal target levels. Lake Michigan’s mean level remains below the long-term average. Statewide, shallow groundwater levels were above normal with an average departure of +0.8 feet. Combined with the change in normal monthly groundwater levels between October and November, a 1.1-foot decrease in departures from last month was observed (Figure 1). Levels averaged 0.4 feet lower than October levels and were approximately 2.4 feet above November levels of last year.

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Figure 1. Statewide departures from normal Note: The WARM Network maps and extended network descriptions appear in the January and July issues. Water and Atmospheric Resources Monitoring Program | www.isws.illinois.edu/warm Illinois State Water Survey | Institute of Natural Resource Sustainability | University of Illinois at Urbana-Champaign Contact Bob Scott: (217) 333-4966, email: [email protected]

Weather/Climate Information (Jim Angel and Bob Scott) Temperatures across Illinois for November were below average (Figure 2 and Table 1). Charleston (Coles County) reported the warmest temperature in the state with a high of 82° F on November 2. Altona (Knox County) reported the coolest temperature in the state with a low of 8° F on November 22. Precipitation for November was below average statewide (Figure 2 and Table 1). Lawrenceville (Lawrence County) reported the highest one-day precipitation of 1.64 inches on November 13, while Newton (Jasper County) reported the highest monthly total of 3.13 inches. This was the tenth wettest June-November (6 months), the third wettest January-November (year to date), and the second wettest December-November (12 months) since 1895. Snowfall for November was present in the northern two-thirds of Illinois from a storm system that swept through on November 30-December 1. November snowfall totals were between 1 and 2 inches at most locations through November 30. Severe weather of any significance was not reported in November. Illinois Climate Network (ICN) Data. Average daily wind speeds across Illinois for November (Figure 3) ranged from 4.3 mph at Dixon Springs to 11.9 mph at Monmouth. Monmouth reported the highest wind gust for the month, 36 mph, on November 6. The prevailing wind direction for the month was southwesterly to westerly across Illinois. Wind speeds in excess of 8 mph during the month varied from 92 hours at Dixon Springs to approximately 525 hours at Monmouth. (November has 720 hours.) Average air temperatures in November ranged from 36° F at Stelle to 44° F at Carbondale. Solar radiation totals in November ranged from 198 Mega-Joules per meter squared (MJ/m2) at Freeport to near 274 MJ/m2 at Dixon Springs. Potential evapotranspiration observations varied from 1.2 inches at Freeport to 1.8 inches across far southern Illinois. Soil temperatures in Illinois during November ranged from 38° F at Big Bend to 49° F at Carbondale (4-inch level) and from 44° F at Big Bend to 52° F at Dixon Springs (8-inch level). Extended climate outlooks issued by the U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Climate Prediction Center for December call for below normal temperatures and equal chances of above, below, and normal precipitation across the state. Outlooks for climatological winter (December through February) call for above normal temperatures and equal chances of above, below, and normal precipitation statewide.

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Figure 2. Illinois temperature and precipitation during November 2008

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Table 1. Illinois Precipitation (inches) and Temperature (ºF) by Crop Reporting District Crop Reporting District

Last Month Nov 08 % Temp Amount Avg Dev

Last 3 Months Sep 08% Temp Nov 08 Avg Dev

Last 6 Months Jun 08% Temp Nov 08 Avg Dev

Last 12 Months Dec 07% Temp Nov 08 Avg Dev

Northwest 1.40 55 0.1 11.41 131 0.1 24.61 116 -0.1 44.73 Northeast 1.16 40 -0.6 14.34 159 -0.1 26.55 126 -0.2 45.83 West 1.03 36 -0.5 13.43 143 -0.5 29.29 139 -0.8 48.94 Central 1.05 36 -1.0 14.34 159 -0.5 27.15 132 -0.7 47.72 East 1.13 37 -1.4 12.64 142 -0.3 24.71 118 -0.4 48.68 West-southwest 1.16 34 -1.6 12.96 140 -0.8 28.67 144 -0.8 53.77 East-southeast 2.14 56 -2.4 10.34 104 -0.4 24.94 116 -0.4 53.51 Southwest 2.01 47 -2.3 9.12 87 -0.6 19.34 90 -0.6 54.18 Southeast 2.76 64 -2.7 8.34 80 -0.2 18.44 86 -0.1 56.08 State Average 1.51 46 -1.3 11.99 127 -0.4 25.16 120 -0.5 50.22 ________________ Note: Data are provisional. Complete, quality-controlled data are available about six months after a given month.

123 125 130 128 130 142 130 127 126 129

-1.3 -1.1 -1.5 -1.4 -1.1 -1.3 -0.9 -0.8 -0.4 -1.1

Soil Moisture Information (Bob Scott) Precipitation during November was below to much below average across all of Illinois, especially in central areas, where roughly one-third of normal precipitation was recorded. Consequently, near-surface soil moisture content fell below normal for the first time since February (Figure 4). In the 0- to 6-inch layer, values ranged from 60 percent of normal at Ina (Rend Lake) to 105 percent at DeKalb and Brownstown, with an anomalous value of 153 percent at Topeka. Conditions in the 6- to 20-inch layer were a little drier, varying from 33 percent at Springfield to 122 percent at Carbondale. Soil moisture in the 20- to 40- inch layer was above normal, except over central Illinois, ranging from 56 percent at Springfield and Topeka to 153 percent at Olney. Conditions varied the greatest in the 40- to 72-inch layer, ranging from 60 percent of normal at Topeka to 191 percent at Ina. Overall, soil moisture in Illinois at the end of November was below normal (Figure 1). Compared to conditions at the end of October, changes in soil moisture at the end of November varied statewide, but generally were small (Table 2). Moisture in the 0- to 6-inch layer increased by 44 percent at Topeka and 24 percent at Olney, but decreased by 27 percent at Ina. Other sites reported changes under 13 percent. In the 6- to 10-inch layer, increases occurred at Brownstown, Carbondale, and Olney (11-18 percent), while changes at the remaining sites were 8 percent or less. Similarly, in the 20- to 40-inch layer, all stations reported changes of 12 percent or less.

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Average 8 Inch Soil Temperature (deg F)

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Figure 3. November monthly averages and totals as collected by the Illinois Climate Network

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Average Wind Direction (deg)

0 - 6 inch Soil Layer 100

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150 150 125 175 150

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Figure 4. December 1 observed percent-of-normal soil moisture based on 1985-1995 mean

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Table 2. Soil Moisture in Various Layers on December 1, 2008

Location Freeport (NW) DeKalb (NE) Monmouth (W) East Peoria (C) Topeka (C) Stelle (E) Champaign (E) Bondville (E) Perry (WSW) Springfield (WSW) Brownstown (ESE) Olney (ESE) Belleville (SW) Carbondale (SW) Ina (SE) Fairfield (SE) Dixon Springs (SE)

Dec 1 0-6 (inches)

Change from Nov 1 (%)

Dec 1 6 - 20 (inches)

Change from Nov 1 (%)

Dec 1 20 - 40 (inches)

Change from Nov 1 (%)

2.2 2.1 1.7 2.1 1.4 1.7 1.8 1.7 2.1 1.7 2.2 1.8 1.8 2.2 1.5 1.6 2.2

3 -1 8 -3 44 -11 13 -10 -7 -11 0 24 9 12 -27 6 11

5.1 5.3 4.3 5.2 2.6 4.8 5.1 4.9 4.8 4.2 5.1 4.4 4.7 5.0 4.9 5.1 5.4

-2 -1 -3 -2 1 -7 -2 -5 -6 -3 11 18 2 11 -3 8 4

7.5 7.5 7.0 7.8 2.5 6.9 7.1 7.6 7.3 7.1 7.3 7.3 7.6 7.8 7.0 7.9 7.9

-1 -2 -3 -1 -3 -11 -2 -1 -3 -2 -12 2 0 8 -9 5 1

Surface Water Information (Bill Saylor and Vern Knapp) River and stream discharge and stage data are obtained from gaging stations operated by the U.S. Geological Survey (USGS) or the U.S. Army Corps of Engineers (USACE). The USGS gaging station network is supported, in part, by the Illinois Department of Natural Resources Office of Water Resources, ISWS, and the USACE. Provisional discharge data are obtained from the USGS. Table 3 lists the provisional peak stage for the current month compared to flood stage at selected streamgaging stations located on the Illinois, Mississippi, and Ohio Rivers. The peak stage is determined from the daily morning readings posted by the National Weather Service and/or the USACE. The Illinois, Mississippi, and Ohio Rivers remained below flood stage in November. Provisional monthly mean flows for 26 streamgaging stations located throughout Illinois are shown in Table 4. Mean values posted by the USGS are listed if available; otherwise, daily mean discharge data posted by the USGS are used to estimate the mean flow for the month. Long-term mean flows for each month are published by the USGS. The month’s median flow for each station listed in Table 4 was determined by ranking the November mean flow for each year of record, and selecting the middle value, 50 percent exceedence probability. The statewide percent of historical mean flow and percent of historical median flow are calculated by dividing the sum of the average flows this month at stations in Table 4 by the sum of the historical mean and median flows calculated for the month, respectively, at the same stations. This method is intended to weight individual observations proportionately in the aggregate comparison. (The Illinois River and Rock River stations are excluded from the statewide calculation because other rivers listed in Table 4 contribute to their flow.) Mean provisional flow statewide was above the median value for November (170 percent of the median) and below the long-term mean for the month (93 percent of the mean). Mean streamflow conditions throughout Illinois ranged from normal to above normal. Water-Supply Lakes and Major Reservoirs. Table 5 lists reservoirs in Illinois, their normal pool or target water surface elevation, and other data related to observed variations in water surface elevations. Reservoir levels are obtained from a network of cooperating reservoir operators who are contacted each month by ISWS staff for the current water levels. Reservoir levels are reported in terms of their difference from normal pool (or target level). The average of the month-end readings for the period of record is reported in terms of the difference from normal pool

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Table 3. Peak Stages for Major Rivers during November 2008 River

Station

River mile*

Flood stage (feet)*

Peak stage (feet)**

Date

Morris La Salle Peoria Havana Beardstown Hardin

263.1 224.7 164.6 119.6 88.6 21.5

16 20 18 14 14 25

5.8 12.5 12.3 9.3 10.7 20.6

01 02 15 01 01 01

Dubuque Keokuk Quincy Grafton St. Louis Chester Thebes

579.9 364.2 327.9 218.0 180.0 109.9 43.7

17 16 17 18 30 27 33

8.1 4.8 12.0 15.9 11.0 14.2 18.2

18 17 20 01 01 01 01

Illinois

Mississippi

Ohio Cairo 2.0 40 17.2 01 ________________ Notes: * River mile and flood stage from River Stages in Illinois: Flood and Damage Data, Illinois Department of Natural Resources, Office of Water Resources, August 2004 (except as revised by the National Weather Service). ** Peak stage based on daily a.m. readings, not instantaneous peak.

or target level (column 6 of Table 5), and the number of years of record for each reservoir also is given (column 7). Most reservoirs serve as public water supplies, with the exceptions noted in the last column. Compared to end-of-October water levels at 33 reservoirs, end-of-November water levels were lower at 19 reservoirs, slightly higher at four reservoirs, and the same as at the end of last month at 10 reservoirs. For the 33 reservoirs with observations reported at the end of November, water levels at 17 reservoirs were below normal pool (or target operating level), four reservoirs were above normal pool, and 12 reservoirs were at normal pool or spillway level. Sparta Reservoir was intentionally drawn down to facilitate work on the water plant intake. Major Reservoirs. Compared to water levels at the end of October, at the end of November the water surface level at Lake Shelbyville was 2.5 feet lower, Rend Lake was 0.3 feet lower, and Carlyle Lake was 0.1 feet higher. At the end of November, the water surface level at Rend Lake was 0.1 feet below spillway elevation, Carlyle Lake water surface level was 2.1 feet above its November 1 target level (or 0.1 feet above its October target level), and Lake Shelbyville was 0.2 feet below its seasonal target level. Great Lakes. Current month mean and end-of-month values are provisional and are relative to International Great Lakes Datum 1985. The November mean level for Lake Michigan was 577.4 feet, compared to a mean level of 576.7 feet in November 2007. The long-term average lake level for November is 578.7 feet, based on 1918-2007 data. Historically, the lowest mean level for Lake Michigan in November occurred in 1964 at 576.3 feet, and the highest level occurred in 1986 at 582.0 feet. The month-end level of Lake Michigan was 577.3 feet.

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Table 4. Provisional Mean Flows, November 2008 Station

Drainage Years area of (sq mi) record

2008 Long-term flows mean flow Mean* Median (cfs) (cfs) (cfs) Flow condition

Rock River at Rockton 6363 72 4490 3516 3199 above normal Rock River near Joslin 9549 64 6050 5145 4712 normal Pecatonica River at Freeport 1326 88 920 744 614 above normal Green River near Geneseo 1003 69 742 441 327 above normal Edwards River near New Boston 445 69 166 165 82 above normal Kankakee River at Momence 2294 90 2203 1563 1202 above normal Iroquois River near Chebanse 2091 83 581 1000 458 normal Fox River at Dayton 2642 88 2148 1478 1311 above normal Vermilion River at Pontiac 579 63 200 241 58 normal Spoon River at Seville 1636 90 510 603 301 normal LaMoine River at Ripley 1293 84 352 515 193 normal Bear Creek near Marceline 349 63 20 156 26 normal Mackinaw River near Congerville 767 58 419 274 63 above normal Salt Creek near Greenview 1804 65 780 793 277 above normal Sangamon River at Monticello 550 95 197 246 85 normal South Fork Sangamon near Rochester 867 58 169 276 84 above normal Illinois River at Valley City 26,743 68 15,930 14,400 11,505 above normal Macoupin Creek near Kane 868 78 124 313 95 normal Vermilion River near Danville 1290 85 240 616 277 normal Kaskaskia River at Vandalia 1940 37 979 976 708 normal Shoal Creek near Breese 735 63 74 305 139 normal Embarras River at Ste. Marie 1516 93 273 753 332 normal Skillet Fork at Wayne City 464 87 574 269 74 above normal Little Wabash below Clay City 1131 92 314 595 217 normal Big Muddy at Plumfield 794 36 76 422 116 normal Cache River at Forman 244 83 32.7 198 89 normal ________________ Notes: N/A = not available Much below normal flow = 90-100% chance of exceedence. Below normal flow = 70-90% chance of exceedence. Normal flow = 30-70% chance of exceedence. Above normal flow = 10-30% chance of exceedence. Much above normal flow = 0-10% chance of exceedence. *As reported in U.S. Geological Survey (USGS) Water Resources Data, Illinois, Water Year 2007.

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Percent Days of chance of data this exceedence month 22 32 26 18 27 22 47 18 32 32 38 51 20 27 34 28 29 41 51 41 55 54 15 43 55 62

30 30 30 30 30 30 30 30 27 30 30 30 30 30 30 30 30 30 26 30 30 30 30 30 30 30

Table 5. Reservoir Levels in Illinois, November 2008

Reservoir

County

Current level Normal pool difference from Monthly or target normal or target change level (feet) (feet) (feet)

Average difference from normal or target (feet)

Years of record

October reported pumpage (million gallons)

Altamont Effingham 582.0 -1.4 -0.3 -2.8 25 7.0 Bloomington McLean 719.5 0.0 -0.1 -4.7 25 N/A Canton Fulton 577.5 -0.2 -0.2 -2.7 18 68.4 Carlinville Macoupin 571.1 -0.5 -0.3 -1.0 25 22.8 Carlyle(1) Clinton 443.0 +2.1 +0.1 +3.0 30 N/A Coulterville Randolph 515.9 N/A N/A -2.0 11 N/A Macon 612.5 +1.4 -0.2 +0.3 25 1,088.2 Decatur(1,3) Evergreen(4) Woodford 720.0 0.0 -0.1 -3.9 18 N/A Glenn Shoals(2) Montgomery 590.0 0.0 0.0 -0.6 14 w/Hillsboro Greenfield Greene 566.2 -0.4 -0.2 -1.3 11 2.8 Highland Madison 500.0 -0.4 -0.1 -0.3 20 36.2 Montgomery 589.0 0.0 0.0 -0.3 14 36.8 Hillsboro(2) Jacksonville(2) Morgan 644.0 0.0 0.0 -0.6 9 w/Mauvaise Terre Kinkaid Jackson 420.0 -0.5 0.0 -0.7 20 58.3 Lake of Egypt Williamson 500.0 -0.8 +0.2 -0.8 15 N/A Mattoon Coles 632.0 0.0 0.0 -0.9 15 w/Paradise Mauvaise Terre(2) Morgan 588.5 0.0 0.0 0.0 12 no meter Mt. Olive (new) Macoupin 600.0 N/A N/A -0.4 7 w/Mt. Olive (old) Mt. Olive (old) Macoupin 654.0 -0.9 -0.3 -0.8 12 6.6 Nashville(3) Washington 503.8 -1.6 -0.5 -1.0 23 19.8 Pana Christian 641.6 -0.7 -0.2 -1.9 24 N/A Paradise Coles 685.0 0.0 0.0 -0.6 18 67.2 Paris (east) Edgar 660.0 -0.8 +0.1 -1.1 23 39.9 Paris (west) Edgar 660.1 0.0 0.0 +0.1 13 w/Paris (east) Pinckneyville Perry 445.0 -2.2 -0.2 -1.7 14 20.2 Pittsfield Pike 596.0 +0.3 -0.1 -0.6 20 15.6 Marion 477.0 +0.3 0.0 N/A N/A 105.3 Raccoon(1) Rend Franklin 405.0 -0.1 -0.3 +0.7 30 N/A Salem(3) Marion 546.5 -1.0 -0.8 -1.0 13 32.6 Shelbyville(1) Shelby 600.2 -0.2 -2.5 +0.9 30 Not PWS Randolph 497.5 -3.7 -0.3 -0.9 12 17.0 Sparta(3) Spring(4) McDonough 654.0 N/A N/A -1.0 25 62.1 Springfield(1,3) Sangamon 559.6 0.0 -0.2 -1.9 25 628.0 Taylorville Christian 590.0 -0.2 -0.1 -1.1 15 57.6 Vermilion(4) Vermilion 581.7 0.0 +0.2 -0.5 23 242.0 Virginia Cass 575.0 0.0 0.0 -0.2 19 Not PWS _______________ Notes: Normal pool and target level datum is NGVD 1929. Current levels reported represent water surface levels at the end of the month, not the monthly average. Average difference from normal or target level is the arithmetic average of reported month-end values for the period of record indicated. Years of record = total number of monthly readings included in month-end average. Total period of record may be longer. Not PWS = not a public water supply. N/A = not available. (1) Target operating level may vary. Seasonal target levels this month represent December 1 values. (2) Instrumentation not available to measure height of water elevation above spillway. (3) Natural inflow can be supplemented by other sources. (4) Normal pool elevations have changed during period of record reported.

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Groundwater Information (Ken Hlinka)

Comparison to Average Levels. Shallow groundwater levels in 16 observation wells, which are remote from pumping centers, were above average for the month. November levels were 0.8 feet above normal and ranged from 5.1 feet below to 3.2 feet above normal levels (Table 6). Comparison to Previous Month. Shallow groundwater levels were below those of October. Levels averaged 0.4 feet lower and ranged from 2.8 feet below to 1.5 feet above levels of last month. Comparison to Same Month, Previous Year. Shallow groundwater levels in November were above levels measured one year ago. Levels averaged 2.4 feet above and ranged from 3.1 feet below to 6.8 feet higher than during November 2007.

Table 6. Month-End Shallow Groundwater Level Data Sites, November 2008



Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Well name

County

Galena Mt. Morris Crystal Lake Cambridge Fermi Lab Good Hope Snicarte Coffman Greenfield Janesville St. Peter SWS #2 Boyleston Sparta SE College Dixon Springs Bondville

JoDaviess Ogle McHenry Henry DuPage McDonough Mason Pike Greene Cumberland Fayette St. Clair Wayne Randolph Saline Pope Champaign

________________ Notes: * Data not used in analysis N/A - Data not available.

Well depth (feet) 25.00 55.00 18.00 42.00 17.00 30.00 40.30 28.00 20.70 11.00 15.00 80.00 23.00 27.00 10.19 8.63 21.00

This month’s reading (depth to water, feet) 20.20 17.09 4.15 *16.96 7.77 6.60 35.49 10.47 12.71 5.68 2.89 14.50 3.17 8.29 8.70 *8.68 3.98 Averages

15-year avg. level (feet)

Deviation from Period of Previous record avg. month (feet) (feet)

Previous year (feet)

1.04 3.50 1.53 N/A 0.37 3.03 2.14 2.64 2.83 0.02 0.44 -0.24 2.78 0.77 -2.60 -3.05 2.37

1.32 3.15 1.51 N/A -0.27 2.84 2.09 2.51 1.85 -0.21 -0.20 1.20 2.88 1.14 -3.39 -5.08 1.18

-0.62 -0.71 -0.51 N/A -0.23 -0.75 -0.48 -2.75 -1.03 0.14 0.58 -0.25 1.45 -0.26 0.74 0.00 -0.62

1.04 1.67 0.47 N/A 1.61 3.68 N/A 6.83 5.95 0.30 1.07 2.91 5.93 4.11 -0.06 -3.06 4.08

1.10

0.79

-0.35

2.44

Addendum (Nancy Westcott) Imperial Valley Precipitation. November 2008 precipitation amounts (Figure 5a) were light. Monthly gage totals were greatest in the southwestern and northern portions of the network, and precipitation was lightest in the central and southeastern regions. Individual gage amounts ranged from 1.26 inches at Site #7 to 0.64 inches at Site #16. The 30-year, 1971-2000, average precipitation amounts for November at Havana and Mason City are 3.26 and 2.95 inches, respectively. The November 2008 network average of 0.97 inches was about 35 percent of the 16-year (1992-2007) IVWA November network average of 2.75 inches. Cook County Precipitation. November 2008 precipitation amounts (Figure 5b) were also light. The greatest precipitation was found in the northern region of the county, and the lightest precipitation was in the southeastern portion of the network. Precipitation values ranged from 1.68 inches at Site #2 (Winneka) to 0.57 inches at Site #19 (Avenue 0, near Wolf Lake). The November 2008 network average of 1.03 inches was about 35 percent of the 19-year (1989-2007) November network average of 2.95 inches.

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Imperial Valley Water Authority Precipitation (inches) a. Imperial Valley November 2008 Scale of Miles 0

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November 2008 Figure 5. Long-term raingage network precipitation totals (inches) for November 2008

Data sources for information in this publication include the following: CPC - Climate Predication Center, http://www.cpc.ncep.noaa.gov/index.php ISWS - Illinois State Water Survey, http://www.isws.illinois.edu/ MRCC - Midwestern Regional Climate Center, http://mrcc.isws.illinois.edu/ NCDC - National Climate Data Center, http://www.ncdc.noaa.gov/ NWS - National Weather Service, http://www.nws.noaa.gov/ USACE - U.S. Army Corp of Engineers, http://rivergages.com, http://www.lre.usace.army.mil/greatlakes/hh/ USGS - U.S. Geological Survey, http://waterdata.usgs.gov/il/nwis WARM - Water and Atmospheric Resources Monitoring Program, http://www.isws.illinois.edu/warm/

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0.75