Roach · Rutilus rutilus

Roach in the River Colnebrook

Largest measured roach: 29.7 cm

The largest roach measured in Environment Agency surveys of the River Colnebrook was 29.7 cm, recorded at Hythe End on 4 July 2012.

Across 517 measured roach, the median measured length was 13.1 cm.

Surveyors recorded weights for 12 roach. The median was 1.4 oz (0.039 kg) and the largest recorded weight was 6.2 oz (0.175 kg).

RiverFish uses Environment Agency survey measurements rather than rod-and-line angling records. These figures show fish measured during EA surveys of the River Colnebrook.

See roach records across England →

Most recent observation2 June 2026Wraysbury · 11 fish

Largest measured roach: 29.7 cm
Median length: 13.1 cm
Fish measured: 517
Survey locations: 7

Individual EA measurements

Largest measured roach

The largest individual measurements in this river and species dataset. Equal measurements are retained as separate surveyed fish.

Length	Survey date	Survey location	Survey ID
29.7 cm	4 Jul 2012	Hythe End	132439
29.5 cm	25 Jul 2003	Hythe End	76528
28 cm	3 Jun 2010	Hythe End	121759
27.6 cm	21 Aug 2002	Thorney Golf Course	72408
27.5 cm	4 Jul 2012	Hythe End	132439
27.5 cm	20 Nov 2001	Hythe End	73303
27.3 cm	4 Jul 2012	Hythe End	132439
25.4 cm	16 Oct 2001	Thorney Golf Course	73302
25.4 cm	16 Oct 2001	Thorney Golf Course	73302
25.1 cm	14 Jun 2011	Hythe End	126579

Lengths are direct survey measurements. RiverFish does not estimate fish weights from length.

Explore the river

Where roach were found

Each point marks a survey location with at least one roach record.

Choose a point on the map to see what was recorded there.

Map points are approximate and don’t show fishing access. Check local permissions before visiting.

Place surveyed	First recorded	Last recorded	Visits finding roach
Wraysbury	3 Jun 2015	2 Jun 2026	8
Thorney Golf Course	13 May 1986	20 Jun 2023	9
Hythe End	20 Nov 2001	6 Jun 2014	13
Horton Upstream Backloop	24 Apr 2010	24 Apr 2010	1
Horton Middle Site	23 Apr 2010	23 Apr 2010	1
Horton Downstream site	23 Apr 2010	23 Apr 2010	1
Iver	15 May 1986	15 May 1986	1

Choose a point or table row to see the location. More survey visits can mean more records, but not necessarily more fish.

1986–2026

Survey records by year

Each bar shows how many survey visits recorded roach that year.

286

087

088

089

090

091

092

093

094

095

096

097

098

099

000

201

202

203

204

205

106

107

108

109

410

111

212

113

114

115

116

117

118

119

020

021

022

223

124

025

126

Fish measured by surveyors

Measured length distribution

See how the 517 measured fish were spread across different length ranges.

Smallest: 3.7 cm
Lower quarter: 10.3 cm
Median: 13.1 cm
Upper quarter: 17.3 cm
Largest: 29.7 cm

0–99 mm

121

100–199 mm

327

200–299 mm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 12 roach. This is a subset of the measured fish and may not represent the whole population.

Lightest: 0.2 oz (0.0066 kg)
Lower quarter: 0.5 oz (0.0148 kg)
Median: 1.4 oz (0.039 kg)
Upper quarter: 4.3 oz (0.1205 kg)
Heaviest: 6.2 oz (0.175 kg)

These are direct individual weights recorded by Environment Agency surveyors. Combined bulk weights are not included.

More fish in this river

Explore the River Colnebrook

Compare other species with enough survey and measurement data for a detailed page.

European eel Perch Chub Pike Gudgeon Minnow

Before you fish

Good to know

These are past survey records, so the fish present today may be different. Map points are approximate—check local access, permissions and fishing rules before visiting.

Learn how RiverFish uses the data →