Site ID: 1520 Lat. 0.1583 Kenya Nyanza
River: Nzoia Long. 34.1670
Site name: Ukwala Contributing area: 12778 km2 Ratio to Comparison Station: 0.41
Latest measurement: 5-Apr-10 Mean annual runoff: 222 mm (2003-2008)
Hydrologic status: 2 Normal flow Total runoff this year (2010): 65 mm
Latest M/C ratio: 1.03 Seven day total: 4 mm
Estimated current discharge: 102 m3/sec Percent of mean 7-day total: 93.2 % (today's value compared to mean for same period, 2003-2007)
Ice-cover determination: 5 yr recurrence flood: 188 m3/sec (from Log Pearson III analysis)
Status Codes:  1 = Low flow, 2 = Normal flow, 3 = Flood, 4 = Major Flood 184 m3/sec (from Gumbel Extreme Value analysis)
Comparison Station Information:  Rusumo (1870800)           Contributing Area:   sq mi 30879 sq km
(Data from this gaging station are used for the calibration to discharge, with an adjustment for different contributing areas)
Notes:
Discharge and runoff, based on satellite remote sensing (NASA AMSR-E data)
(For U.S, sites, nearby ground station discharge may also be shown)
2008-Present
2002-Present
Annual  Monthly Total Runoff (mm), computed from above satellite-based discharge data
Runoff
(mm) Jan Feb Mar April May June July Aug Sept Oct Nov Dec
87 2002 no data no data no data no data no data no data no data 13.6 15.5 19.5 19.1 19.6
219 2003 19.5 17.4 17.0 17.6 18.1 18.4 20.9 18.7 17.7 19.2 14.9 19.4
223 2004 19.2 18.5 18.0 16.1 17.7 16.9 18.7 18.8 18.6 19.1 19.6 21.3
216 2005 19.7 17.4 19.5 19.5 19.7 18.7 2.3 19.3 19.9 20.2 19.0 20.3
202 2006 21.5 19.8 19.3 23.3 18.9 19.9 21.4 18.3 20.2 19.4 0.0 0.0
234 2007 20.7 19.3 20.0 18.1 19.2 19.7 21.1 19.9 19.3 19.4 18.1 19.3
240 2008 21.3 20.0 22.2 19.2 18.4 17.3 20.4 20.5 19.6 20.8 20.3 20.5
236 2009 20.6 18.3 20.6 17.6 20.2 19.7 20.1 18.6 19.5 20.3 20.8 19.8
65 2010 21.0 18.2 20.9 4.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
7/
Mean Annual Runoff (mm): 9 Standard Deviation: 14
Trend in Annual Runoff (slope):  3.78
Discharge is estimated via a rating equation directly from the remote sensing data (M/C ratio) shown below.
Explanation:   Green line records upwelling microwave emission from a land parcel (ca 10 km x 10 km) near the river; blue line from a parcel centered over the river.
Brown line is their ratio (M/C; scale on right) and is used to estimate river discharge via a rating equation.
Rating equations are being developed and applied on an individual basis. For calibration status, see "notes" entry, above.
GoogleEarth View of Measurement Site
Return
Estimated
Disharge
Data
Date m3/sec
22-Jul-02 93
23-Jul-02 93
24-Jul-02 89
25-Jul-02 72
26-Jul-02 75
27-Jul-02 69
28-Jul-02 82
29-Jul-02 90
30-Jul-02 100
31-Jul-02 100
1-Aug-02
2-Aug-02
3-Aug-02
4-Aug-02
5-Aug-02
6-Aug-02
7-Aug-02
8-Aug-02
9-Aug-02
10-Aug-02 92
11-Aug-02 96
12-Aug-02 96
13-Aug-02 92
14-Aug-02 95
15-Aug-02 91
16-Aug-02 91
17-Aug-02 83
18-Aug-02 88
19-Aug-02 88
20-Aug-02 90
21-Aug-02 95
22-Aug-02 93
23-Aug-02 93
24-Aug-02 95
25-Aug-02 93
26-Aug-02 94
27-Aug-02 90
28-Aug-02 87
29-Aug-02 87
30-Aug-02 83
31-Aug-02 95
1-Sep-02 95
2-Sep-02 96
3-Sep-02 92
4-Sep-02 88
5-Sep-02 86
6-Sep-02 83
7-Sep-02 80
8-Sep-02 80
9-Sep-02 90
10-Sep-02 88
11-Sep-02 98
12-Sep-02 95
13-Sep-02 92
14-Sep-02 99
15-Sep-02 89
16-Sep-02
17-Sep-02
18-Sep-02
19-Sep-02
20-Sep-02
21-Sep-02 96
22-Sep-02 96
23-Sep-02 91
24-Sep-02 91
25-Sep-02 93
26-Sep-02 91
27-Sep-02 96
28-Sep-02 96
29-Sep-02 95
30-Sep-02 96
1-Oct-02 97
2-Oct-02 95
3-Oct-02 95
4-Oct-02 94
5-Oct-02 98
6-Oct-02 100
7-Oct-02 95
8-Oct-02 96
9-Oct-02 91
10-Oct-02 91
11-Oct-02 92
12-Oct-02 87
13-Oct-02 81
14-Oct-02 84
15-Oct-02 84
16-Oct-02 82
17-Oct-02 82
18-Oct-02 87
19-Oct-02 87
20-Oct-02 97
21-Oct-02 98
22-Oct-02 99
23-Oct-02 93
24-Oct-02 91
25-Oct-02 97
26-Oct-02 97
27-Oct-02 107
28-Oct-02 105
29-Oct-02 93
30-Oct-02 95
31-Oct-02 92
1-Nov-02 92
2-Nov-02 99
3-Nov-02 105
4-Nov-02 105
5-Nov-02 95
6-Nov-02 97
7-Nov-02 93
8-Nov-02 95
9-Nov-02 100
10-Nov-02 100
11-Nov-02 100
12-Nov-02 98
13-Nov-02 94
14-Nov-02 88
15-Nov-02 93
16-Nov-02 92
17-Nov-02 95
18-Nov-02 101
19-Nov-02 88
20-Nov-02 88
21-Nov-02 89
22-Nov-02 88
23-Nov-02 90
24-Nov-02 90
25-Nov-02 88
26-Nov-02 97
27-Nov-02 97
28-Nov-02 94
29-Nov-02 92
30-Nov-02 88
1-Dec-02 88
2-Dec-02 90
3-Dec-02 90
4-Dec-02 94
5-Dec-02 101
6-Dec-02 101
7-Dec-02 95
8-Dec-02 90
9-Dec-02 81
10-Dec-02 89
11-Dec-02 92
12-Dec-02 97
13-Dec-02 97
14-Dec-02 83
15-Dec-02 83
16-Dec-02 87
17-Dec-02 90
18-Dec-02 96
19-Dec-02 89
20-Dec-02 82
21-Dec-02 82
22-Dec-02 82
23-Dec-02 99
24-Dec-02 103
25-Dec-02 105
26-Dec-02 101
27-Dec-02 102
28-Dec-02 100
29-Dec-02 100
30-Dec-02 103
31-Dec-02 103
1-Jan-03 100
2-Jan-03 98
3-Jan-03 95
4-Jan-03 91
5-Jan-03 91
6-Jan-03 87
7-Jan-03 87
8-Jan-03 93
9-Jan-03 91
10-Jan-03 94
11-Jan-03 92
12-Jan-03 88
13-Jan-03 91
14-Jan-03 91
15-Jan-03 95
16-Jan-03 96
17-Jan-03 91
18-Jan-03 93
19-Jan-03 93
20-Jan-03 92
21-Jan-03 99
22-Jan-03 92
23-Jan-03 92
24-Jan-03 88
25-Jan-03 87
26-Jan-03 89
27-Jan-03 92
28-Jan-03 92
29-Jan-03 104
30-Jan-03 104
31-Jan-03 100
1-Feb-03 100
2-Feb-03 95
3-Feb-03 99
4-Feb-03 103
5-Feb-03 103
6-Feb-03 106
7-Feb-03 104
8-Feb-03 104
9-Feb-03 76
10-Feb-03 83
11-Feb-03 83
12-Feb-03 90
13-Feb-03 97
14-Feb-03 102
15-Feb-03 102
16-Feb-03 89
17-Feb-03 89
18-Feb-03 81
19-Feb-03 82
20-Feb-03 83
21-Feb-03 85
22-Feb-03 86
23-Feb-03 91
24-Feb-03 91
25-Feb-03 93
26-Feb-03 92
27-Feb-03 92
28-Feb-03 74
1-Mar-03 66
2-Mar-03 59
3-Mar-03 59
4-Mar-03 82
5-Mar-03 85
6-Mar-03 88
7-Mar-03 88
8-Mar-03 89
9-Mar-03 78
10-Mar-03 78
11-Mar-03 75
12-Mar-03 75
13-Mar-03 69
14-Mar-03 68
15-Mar-03 66
16-Mar-03 70
17-Mar-03 71
18-Mar-03 82
19-Mar-03 82
20-Mar-03 83
21-Mar-03 84
22-Mar-03 80
23-Mar-03 95
24-Mar-03 104
25-Mar-03 90
26-Mar-03 98
27-Mar-03 86
28-Mar-03 86
29-Mar-03 92
30-Mar-03 92
31-Mar-03 91
1-Apr-03 91
2-Apr-03 92
3-Apr-03 78
4-Apr-03 78
5-Apr-03 68
6-Apr-03 74
7-Apr-03 70
8-Apr-03 74
9-Apr-03 79
10-Apr-03 80
11-Apr-03 82
12-Apr-03 87
13-Apr-03 87
14-Apr-03 88
15-Apr-03 83
16-Apr-03 80