River Slea

A stream near Frithend, Hampshire. No gauge of its own: what the river map and the banked data say about it.

The River Slea is a stream on Ordnance Survey’s river map near Frithend, Hampshire, with about 3.2 km of mapped channel. On the map it flows into the River Wey, which flows on into the River Thames and out to the sea.

Next gauge downstream

Tilford on the River Wey, about 12 km along the river below where the River Slea ends on the map.

0.17 mASD Normal · steady 34 min ago

After that, Borough Road, about 28 km along the river.

No gauge measures the River Slea itself. A gauge downstream shows water that has already passed it, mixed with everything else that has joined on the way, so it says nothing exact about this stream.

Water-sampling points on the River Slea

1 Environment Agency sampling point is placed on this stream. These are dated samples taken by hand, not live readings, and FloodRadar does not grade them.

Slea at Sleaford Bridge
Last sampled 28 Aug 2026 · 34 days ago · 22 samples banked

A sample is taken on a date; it says nothing about the water today. A sample below an overflow does not by itself show where anything in it came from.

Water samples: Environment Agency Water Quality Archive, © Environment Agency and/or database right 2026, Open Government Licence v3.0.

On the map

The map needs JavaScript. Everything it shows is listed on this page.

The blue line is the River Slea; grey lines are other mapped watercourses. Lines from OS Open Rivers (edition 2026-04).

The River Wey, the river it joins →GU10 4HH, a postcode page near where it ends on the map (about 320 m away) →All rivers with gauges →

What this page can and cannot tell you

Its line, its name and where it flows come from Ordnance Survey’s river map (OS Open Rivers, edition 2026-04), which leaves out many small streams, ditches and culverts. “Flows into” is the map’s word: a channel that is not on the map is not shown here, which does not mean it is not there.
No gauge measures the River Slea itself, so its own level is not known here.
No storm overflow is placed on this stream on the river map. That is not the same as none: the map cannot place every overflow.
Water samples are England’s only (the Environment Agency’s archive), placed where the map can place their sampling point.
Nothing on this page says whether any place floods. For an address, see its postcode page.

This uses Environment Agency flood and river level data from the real-time data API (Beta). Licence: Open Government Licence v3.0.