U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2020–3029

July 2020

Hydrologic Conditions in Kansas, Water Year 2019

The U.S. Geological Survey 

(USGS), in cooperation with Federal, 

State, and local agencies, maintains 

a long-term network of hydrologic 

monitoring stations in Kansas. In water 

year (WY) 2019, this network included 

217 real-time streamgages (fig. 1). A WY

is the 12-month period from October 1 

through September 30 and is designated 

by the calendar year in which it ends.

Real-time hydrologic data are verified by USGS personnel throughout the

year providing regular measurements of 

streamflow, lake levels, and groundwater

levels. These data and associated analyses 

provide a unique overview of hydrologic 

conditions and help improve the understanding of Kansas’ water resources. 

Annual assessments of hydrologic conditions are made by comparing statistical 

analyses of current and past WY data 

for the period of record. Long-term 

monitoring of hydrologic conditions in 

Kansas provides important information 

for many functions including managing 

water resources, protecting human life 

and property, maintaining agricultural 

and industrial activities, the operation of 

reservoirs, the development of infrastructure, accurate ecological assessments, and 

recreational purposes.

Preceding Conditions and 

Precipitation

Despite some isolated, heavy 

precipitation events, overall streamflow

and drainage basin runoff conditions

decreased for the State of Kansas 

between WYs 2017 and 2018. During 

WY 2017, precipitation in most of the 

State was classified as normal to below

normal, which resulted in drought conditions in much of central and eastern 

Kansas at the end of WY 2017 (fig. 2A). 

During WY 2018, most of the eastern 

half of the State experienced normal 

(average) to below normal precipitation, 

whereas parts of the western half of the 

State experienced above normal precipitation, particularly north-central Kansas 

(fig. 2B). South-central and eastern 

Kansas experienced below and much 

below normal precipitation, resulting in 

abnormally dry to extreme drought conditions at the end of WY 2018 (fig. 3) that 

continued into WY 2019.

Heavy rainfall events in October and 

November of 2018 ended drought conditions, and by the beginning of December, 

dry conditions were virtually nonexistent in Kansas and remained that way 

throughout WY 2019 (National Drought 

Mitigation Center, 2019). Overall, normal 

to much above normal precipitation 

occurred throughout WY 2019 (fig. 4A) 

(National Oceanic and Atmospheric

KANSAS

River basins

Base from U.S. Geological Survey digital data 

Albers Equal Area Conic projection 

North American Datum of 1983 

EXPLANATION

Major cities

Rivers

Streamage location

Tuttle Creek 

Lake

Cheney Lake

Cedar Bluff Lake Cedar Bluff Lake

Horse Thief Reservoir

Kanopolis Lake

Wilson Lake Perry Lake

Clinton 

Lake

Hillsdale 

Lake

Melvern 

Lake

Pomona Lake

Milford 

Lake

South Fork Republican 

River Basin

Cimarron River Basin

Kansas 

River Basin

0 50 100 MILES

0 50 100 KILOMETERS

Figure 1. United States Geological Survey streamgages in Kansas and selected river basins.
EXPLANATION

Normal precipitation, in percent

175

150

125

110

100

100

90

75

50

25

A. Water year 2017

B. Water year 2018

Figure 2. Comparison of statewide 

percentage of normal precipitation 

(1981–2010) (National Oceanic and 

Atmospheric Administration, 2019). 

A, Water year 2017. B, Water year 2018.

EXPLANATION

Drought intensity

Abnormally dry

Moderate drought

Severe drought

Extreme drought 

Exceptional drought

A. Water year 2017

B. Water year 2018

Figure 3. Comparison of drought 

conditions in Kansas (National Drought 

Mitigation Center, 2019). A, At the end of 

water year 2017. B, At the end of water 

year 2018.

Administration, 2019). The above normal 

precipitation for WY 2019 extended from 

the northeast portion of the State, with 

more than 20 inches of above normal 

annual rainfall occurring in places, down 

to the southwest portion of the State, with 

only a small area experiencing normal 

precipitation (National Weather Service, 

2019) (fig. 4B).

Streamflow Conditions 

and Drainage Basin 

Runoff

Kansas experienced several 

record-breaking hydrologic conditions 

during WY 2019, including the most 

precipitation within a month on record; 

out of 125 years of record, the precipitation for May (10.26 inches) beat the 1951 

record of 9.36 inches (National Weather 

Service, 2019). Additionally, in WY

2019, Kansas experienced the second 

largest amount of precipitation in a water 

year within 130-years of record (National 

Oceanic and Atmospheric Administration,

2019) and the most cumulative runoff on

record (fig. 5A).

Runoff, or streamflow per unit

area, is a good indicator of precipitation and streamflow for a given drainage

basin. The monthly average runoff graph

shows the continuity of above normal 

hydrologic conditions during WY 2019 

(fig. 5B). Streamflow conditions were

much above normal in Kansas during 

the first quarter of the WY (October to

A. Percentage of normal precipitation, water year 2019

B. Inches of precipitation above normal, water year 2019

Figure 4. Precipitation for water year 2019 (National Oceanic and Atmospheric 

Administration, 2019). A, Statewide percentage of normal (1981–2010) precipitation for water 

year 2019. B, Statewide inches of precipitation above normal (1981–2010) for water year 2019.
B. Monthly average runoff

A. Cumulative daily average runoff

EXPLANATION

Percentile class

lowest — 

10th percentile 5 10 – 24 25 – 75 76 – 90 95 90th percentile — highest

Much below normal Below 

normal Normal Above normal

Runoff

Much above normal

Figure 5. Graphs showing average runoff in Kansas for water year 2019 (U.S. Geological 

Survey 2019a). A, Comparison of cumulative daily average runoff. B, Monthly average runoff.

Low

Above No data

normal

Normal

<10 10–24 25–75

76–90 >90

Below

normal

High

Much below

normal

Much above

normal

Percentile classes

[<, less than; >, greater than]

EXPLANATION

Water Year 2019

October – December 2018

January – March 2019

April – June 2019

July – September 2019

Figure 6. Comparison of monthly 

streamflow conditions across Kansas 

throughout water year 2019 (U.S. Geological 

Survey, 2019a).

December 2018), except for small areas 

in northwest and southwest Kansas, 

which were slightly below normal 

(fig. 6). By January to March, streamflow

conditions in the northern and central 

portions of Kansas remained in the 

normal to much above normal percentile 

class. Above normal streamflow was

maintained through March by a strong 

blizzard in the region. April through June

maintained mostly above normal to high 

streamflow conditions from multiple

widespread precipitation events. In July

through September, the normal to above 

normal trend of streamflow conditions

remained, ending the water year with the 

State in mostly normal to high streamflow conditions (fig. 6).

Due to large precipitation events, 

runoff conditions in most of Kansas

were in the 90th percentile by May, 

with every county but one in northwestern Kansas experiencing normal to 
record high runoff conditions (fig. 7).

Precipitation events began decreasing 

in magnitude by July. In response to

the heavy precipitation, Kansas reservoirs began releasing large outflows to

decrease the elevation of water stored 

in the reservoir’s respective flood pools

(U.S. Army Corps of Engineers, 2019). 

This resulted in streamflow conditions

that were continuously much above 

normal for rivers in the upper and lower 

Kansas River Basin (fig. 1) and normal 

to above normal conditions in most of 

the State. The eastern portion of the 

State, where most of the large reservoirs 

are located, had the highest percentiles 

of monthly streamflow conditions for

the month of July. However, much

of the western part of the State still 

experienced above normal conditions, 

with only the Cimarron and South Fork 

Republican River Basins (fig. 1) experiencing below normal streamflow conditions. By the end of WY 2019, most of

the State was still experiencing above 

normal or normal conditions, which can 

be attributed to the above normal precipitation occurring throughout the WY 

and to reservoir releases.

Record Breaking High 

Water

WY 2019 was characterized by 

sustained high water in much of the 

State. For 69 percent of the WY, one or 

more streamgages were above National 

Weather Service flood stage, leaving 114 days without flooding in the

State (U.S. Geological Survey, 2019b) 

(fig. 8). Photographs of flooding events

taken by USGS personnel are shown in 

figure 9. WY 2019 observed 200 more 

days of flooding than WY 2018 and

194 more days of flooding than WY 2017

(U.S. Geological Survey, 2019b).

Many streamgages observed a 

new peak of record for water elevation in WY 2019. A peak of record in

this case is the highest water-surface 

elevation (referred to as “stage”) in the 

streamgage’s history observed by the 

USGS (U.S. Geological Survey, 2019a) 

(fig. 10). Out of 217 streamgages, 45 of

them observed a new peak of record since 

their establishment by the USGS, which 

varies by site. Previously, the last significant water year with widespread and

Low Above No data

normal Normal

<10 10–24 25–75 76–90 >90

Below

normal

Much below High

normal

Much above

normal

Percentile classes

[<, less than; >, greater than]

EXPLANATION

Figure 7. Streamflow conditions across Kansas throughout May 2019 (U.S. Geological 

Survey, 2019a).

persisting flood conditions was in 1993.

Six streamgages that have been operated 

by the USGS prior to WY 1993 observed 

a new peak of record.

In WY 2019, rivers above flood

stage for more than 30 days in stream 

reaches with a USGS streamgage 

included the Marias Des Cygnes, 

Arkansas, Neosho, Kansas, Republican,

Big Blue, Black Vermillion, Fancy Creek,

Cow Creek, Cottonwood, and Missouri 

Rivers (fig.1). Flood stage is determined by the National Weather Service, 

although not all USGS streamgages have 

a National Weather Service flood stage.

The above average precipitation and 

runoff that occurred in WY 2019 caused

backwater conditions at many sites in 

Kansas, resulting in peak of record and 

sustained high water-surface elevations 

at various streamgages. Backwater is a

condition that occurs when high watersurface elevations downstream or from 

the main channel affect the height and

flow of the water upstream. Streamgages

with data above flood stage for more than

15 days because of backwater from Tuttle 

Creek Lake (06886900) and Milford 

Lake (06857050) included: Republican 

River at Clay Center (06856600), Big

Blue River at Blue Rapids (06884700),

Black Vermillion River near Frankfort

(06885500), and Fancy Creek at Winkler 

(06886500) (fig. 1).

Figure 8. The number of U.S. Geological Survey streamgages above flood stage throughout 

water year 2019 (U.S. Geological Survey, 2019b).
In comparison, WY 2019 and 

WY 1993 were similar in that both were 

affected by multiple widespread precipitation events and prolonged regional 

flooding. There are 122 streamgages

with data dating back to WY 1993 that 

are still in operation today. Out of the 

122 streamgages, in WY 2019, 62 of 

them exceeded the peak water-surface 

elevation recorded in WY 1993.

B

A D

F

E

C

Figure 9. Photographs from water year 2019 flooding. A, Neosho River near Neosho Rapids, 

Kansas (07182390). B, Cottonwood River near Plymouth, Kansas (07182250). C, Slate Creek at 

Wellington, Kansas (07145700). D, Little Arkansas River near Sedgwick, Kansas (07144100). E, Little 

Arkansas River at Alta Mills, Kansas (07143665). F, Slate Creek at Wellington, Kansas (07145700). 

EXPLANATION

Exceeded flood stage

Rivers

Major cities

Streamgage that broke 1993 record

Streamgage that broke previous peak of record

Base from U.S. Geological Survey digital data 

Albers Equal Area Conic projection 

North American Datum of 1983 

Tuttle Creek 

Lake

Perry Lake

Milford Lake

Melvern 

Lake

Hillsdale 

Lake

Pomona 

Lake Clinton 

Lake

Chaney 

Lake

Horse Thief Reservoir

Kanopolis 

Lake

Wilson Lake

Cedar Bluff Lake

0 50 100 MILES

0 50 100 KILOMETERS

Figure 10. Historical record comparison of U.S. Geological Survey streamgages for 

water year 2019 (U.S. Geological Survey, 2019a).

Reservoirs

Many of the USGS monitored 

reservoirs in Kansas were at normal 

levels at the beginning of WY 2019 

(U.S. Geological Survey, 2019b) (fig. 11). 

In 11 of 12 USGS monitored reservoirs 

in Kansas in WY 2019, normal conservation pool elevation was exceeded. Cedar 

Bluff Reservoir was the only USGS

monitored reservoir that did not exceed 

its conservation pool elevation in WY 

2019. Reservoir releases were restricted 

due to high streamflow conditions downstream on the Missouri, Arkansas, and

the Mississippi Rivers, which resulted 

in prolonged flood conditions upstream

of the reservoirs throughout WY 2019. 

When downstream flood conditions

subsided and release restrictions were 

removed, nearly all USGS monitored 

reservoirs released higher outflows,

with higher annual streamflow observed

at the downstream streamgages than 

the previous year, in order to reach the 

respective target water-surface elevation. 

Five reservoirs monitored by the USGS 

had a water-level elevation record set in 

WY 2019. For Tuttle Creek Lake, the 

peak storage in WY 2019 was 830 percent above normal storage. Three USGS 

monitored reservoirs ended the WY with 

less water than at the beginning of the 

WY, three reservoirs ended WY 2019 

with more than twice the percent water 

storage, and six other reservoirs ended 

WY 2019 with more water (fig. 11).

Summary

After the normal (average) conditions in water year (WY) 2017 and the 

below normal conditions in WY 2018, 

above normal to much above normal 

hydrologic conditions existed across 

much of the State in WY 2019. Above
Figure 11. Comparison of U.S. Geological Survey monitored reservoirs in Kansas in water year 2019 (U.S. Geological Survey, 2019b).

normal precipitation throughout the 

State was responsible for the increased 

streamflow, runoff, and record-breaking

events. The WY ended with normal to 

much above normal streamflow across

most of the State because of continued 

reservoir releases and precipitation events 

in September. All USGS monitored reservoirs, except Cedar Bluff Reservoir, filled

their conservation pools; three reservoirs 

ended WY 2019 with more than double 

the normal conservation storage. Despite 

the extreme precipitation in WY 2019, 

three reservoirs ended WY 2019 with 

slightly less water than at the beginning 

of the WY.

References Cited

National Drought Mitigation Center, 

2019, United States drought 

monitor—Kansas: National 

Drought Mitigation Center web 

page, accessed January 1, 2020, at

https://droughtmonitor.unl.edu/.

National Oceanic and Atmospheric

Administration, 2019, Advanced

hydrologic prediction service—2019 

precipitation maps for Kansas: 

National Oceanic and Atmospheric

Administration, Quantitative

Precipitation Estimates map

builder, National Weather Service 

web page, National Operational 

Hydrologic Remote Sensing 

Center, National Weather Service, 

accessed October 1, 2019, at 

https://water.weather.gov/precip/.

National Weather Service, 2019, Severe 

storms and heavy rainfall across 

the Central U.S.: National Oceanic 

and Atmospheric Administration,

National Weather Service web 

page, accessed September 2019, at 

https://www.weather.gov/.

U.S. Army Corps of Engineers, 2019,

Corps of Engineers update on Kansas

River Basin reservoir operations:

U.S. Army Corps of Engineers,

Kansas City District web page, 

accessed December 16, 2019, at 

https://www.nwk.usace.army.mil/

Media/News-Releases/Article/

1863704/corps-of-engineers-updateon-kansas-river-basin-reservoiroperations/.

U.S. Geological Survey, 2019a, 

WaterWatch—Current water resources 

in Kansas: U.S. Geological Survey 

web page, accessed October 20, 2019, 

at https://waterwatch.usgs.gov/.

U.S. Geological Survey, 2019b, 

USGS water data for the Nation: 

U.S. Geological Survey National 

Water Information System database, 

accessed October 20, 2019, at https://

doi.org/10.5066/F7P55KJN.

For more information about this publication 

contact: 

Director, USGS Kansas Water Science Center 

1217 Biltmore Dr. 

Lawrence, Kansas 66049 

(785) 842-9909 

https://usgs.gov/centers/kswsc 

Created by Chantelle Davis 

Publishing support provided by the Rolla and 

Madison Publishing Service Centers

ISSN 2327-6916 (print) 

ISSN 2327-6932 (online) 

https://doi.org/10.3133/fs20203029