028026 Anker at Polesworth 2000
Measuring authority: EA Grid reference: 43 (SK) 263 034 Catchment area (sq km): 368.0
First year: 1966 Level stn. (m OD): 60.40 Max alt. (m OD): 278
Daily mean gauged discharges (cubic metres per second)
DAY JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
1 5.031 2.050 7.469 1.771 3.016 3.470 1.479 1.111 1.303 2.524 15.030 6.254
2 4.492 2.086 6.062 2.800 2.689 2.797 1.349 1.099 1.442 2.501 9.959 5.750
3 4.404 1.852 11.530 12.070 2.558 2.513 1.556 1.380 1.297 2.065 8.919 4.840
4 4.617 2.030 6.516 13.710 2.425 2.344 1.759 1.285 1.064 1.870 5.614 8.184
5 4.240 1.996 4.947 5.421 2.302 2.044 1.512 1.126 0.997 1.838 9.351 10.180
6 4.650 1.995 4.212 3.654 2.208 2.004 1.290 1.008 0.967 1.817 70.410 17.260
7 4.251 2.084 3.782 3.111 2.091 1.908 1.217 0.969 0.979 3.110 37.070 15.770
8 3.817 2.050 3.372 2.766 1.994 1.720 1.220 1.043 0.981 3.780 23.200 40.970
9 3.217 1.861 3.083 2.512 1.938 1.799 1.324 1.044 0.974 4.367 13.370 16.970
10 2.927 2.593 2.893 2.240 1.912 1.725 1.759 0.952 0.921 9.754 7.946 14.680
11 2.879 2.318 2.655 2.904 1.832 1.547 1.707 0.891 0.918 21.930 13.490 20.200
12 3.181 4.403 2.447 6.780 1.809 1.499 1.417 0.912 0.931 21.940 15.400 21.040
13 6.390 3.336 2.341 9.079 1.701 1.446 1.205 0.899 0.917 9.304 7.677 23.680
14 4.770 3.616 2.309 5.554 1.587 1.720 1.135 0.965 1.234 4.449 5.240 12.430
15 3.982 4.125 2.115 4.073 1.538 2.016 1.122 1.088 4.817 3.453 4.446 8.126
16 3.489 4.897 2.054 3.747 1.499 1.543 1.070 1.056 4.558 2.962 5.454 6.206
17 3.316 10.510 2.019 6.155 1.527 1.388 1.022 1.083 1.840 2.514 4.932 5.301
18 3.076 8.625 1.956 9.665 2.350 1.220 0.987 1.192 2.011 2.455 4.727 4.694
19 2.829 6.012 1.877 22.280 2.015 1.176 0.973 2.168 2.579 2.209 6.164 4.664
20 2.697 4.465 1.878 10.610 1.832 1.181 0.951 1.682 4.939 2.125 5.367 4.851
21 2.587 4.399 1.907 6.284 2.416 1.228 0.924 1.246 2.577 4.185 6.457 4.311
22 2.748 3.886 1.881 6.905 1.733 1.231 0.924 1.148 2.053 3.699 15.900 3.973
23 2.455 3.521 2.062 5.794 1.835 1.219 0.899 1.118 1.711 3.151 10.460 3.738
24 2.313 3.526 2.110 4.639 2.018 1.173 0.917 1.032 2.659 2.963 9.427 12.670
25 2.223 4.025 1.877 6.007 1.948 1.143 0.927 0.985 6.416 2.891 12.560 16.180
26 2.172 3.474 1.779 6.066 2.306 1.137 0.980 1.531 15.590 2.585 18.010 7.878
27 2.114 6.459 1.770 6.609 4.756 1.146 1.056 1.914 12.990 3.348 9.936 5.501
28 2.210 23.350 1.763 4.784 13.860 1.092 1.065 1.346 11.200 5.628 19.940 4.636
29 2.313 13.190 1.653 4.461 11.630 1.110 1.746 1.231 5.824 13.890 11.600 3.934
30 2.183 1.716 3.482 4.376 1.422 1.662 1.139 3.077 55.110 6.483 3.435
31 2.018 1.683 3.194 1.211 1.080 35.300 6.081
Average 3.342 4.784 3.088 6.198 2.932 1.632 1.238 1.185 3.326 7.733 13.150 10.460
Lowest 2.018 1.852 1.653 1.771 1.499 1.092 0.899 0.891 0.917 1.817 4.446 3.435
Highest 6.390 23.350 11.530 22.280 13.860 3.470 1.759 2.168 15.590 55.110 70.410 40.970
Monthly total
(million cu m) 8.95 11.99 8.27 16.06 7.85 4.23 3.32 3.17 8.62 20.71 34.09 28.03
Runoff (mm) 24 33 22 44 21 12 9 9 23 56 93 76
Rainfall (mm) 19 70 17 110 74 22 31 49 117 114 110 100
Statistics of monthly data for previous record (Sep 1966 to Dec 1999----incomplete or missing months total 0.2 years)
Mean Avg. 5.630 4.900 4.008 3.072 2.145 1.977 1.316 1.363 1.429 2.185 3.000 4.630
flows: Low 1.299 0.953 0.813 0.657 0.685 0.484 0.343 0.405 0.711 0.729 0.855 1.174
(year) 1976 1976 1976 1976 1976 1976 1976 1976 1977 1970 1978 1975
High 11.320 16.200 9.233 8.230 8.389 4.948 5.580 4.173 3.363 8.109 7.309 9.474
(year) 1999 1977 1979 1998 1969 1999 1968 1980 1992 1993 1992 1978
Runoff: Avg. 41 32 29 22 16 14 10 10 10 16 21 34
Low 9 6 6 5 5 3 3 3 5 5 6 9
High 82 106 67 58 61 35 41 30 24 59 51 69
Rainfall: Avg. 59 48 48 50 55 61 49 60 57 59 58 63
Low 16 9 14 7 11 9 11 15 10 7 28 20
High 106 138 92 100 141 132 111 110 118 127 129 148
Summary statistics Factors affecting runoff
2000
For 2000 For record As % of $ Flow influenced by groundwater abstraction
preceding 2000 pre-2000 and/or recharge.
Mean flow 4.911 2.963 166 $ Augmentation from effluent returns.
Lowest yearly mean 1.213 1976
Highest yearly mean 4.366 1999
Lowest monthly mean 1.185 Aug 0.343 Jul 1976
Highest monthly mean 13.150 Nov 16.200 Feb 1977
Lowest daily mean 0.891 11 Aug 0.234 26 Aug 1976
Highest daily mean 70.410 6 Nov 56.720 24 Jan 1988
10% exceedance 11.760 6.108 193
50% exceedance 2.538 1.676 151
95% exceedance 0.974 0.669 146
Annual total (million cu m) 155.30 93.50 166
Annual runoff (mm) 422 254 166
Annual rainfall (mm) 833 667 125
{1961-90 rainfall average (mm) 653}
Station and catchment description
Crump profile weir with flanking floodbanks to contain out-of-channel flows. Cableway and d/s recorder. Low modular limit
and prone to weed growth, causing variable drowning and uncertainty with high flows. Substantial modification owing to
PWS imports to the catchment. Quite responsive.
Predominantly agricultural catchment (although containing Nuneaton and Hinkley). Lower reaches drain sandstone of the
Coal Measures. Sherwood sandstone and Mercia Mudstone over the remainder of the catchment are widely blanketed with
Boulder Clay.
In line with Natural Environment Research Council policy, the provision of data from the National River Flow Archive confers only a right to use the data. Ownership of the data, or the associated Intellectual Property Rights, will not normally be transferred. Data received from the NRFA must not be sold, or passed on to any third party. Reproduction is authorised, except for commercial purposes, provided the sources is acknowledged.
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