I wouldn't think there is much pressure unless you're getting a strong flow. If it's still it'll be very low.
This briefly explains it simply. https://theconstructor.org/water-resources/forces-acting-dam-structure/5251/?amp=1
If the house is only 70m from the literal river Severn, then there could be a bit of flow!
@Jameo started
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I wouldn't think there is much pressure unless you're getting a strong flow. If it's still it'll be very low.
This briefly explains it simply.
https://theconstructor.org/water-resources/forces-acting-dam-structure/5251/?amp=1