Monday update...
The problem with (3) (other than legality!) is that the pavement doesn't have a handy slope on it, so I'll get a huge puddle outside the house. There's also an old cable TV connection point in the pavement right where the puddle would form, unless I extended the downpipe sideways as well as down the garden (which gets messy and harder to keep a consistent fall on it).
I tried following the pipe fragments through the garden but they disappear pretty quickly. I did unearth a very rusted, broken, 1m section of cast iron pipe that previously seems to have extended through my front wall, but that hole was plugged up a long time ago. Suggests to me that the theoretical connection to the main surface water drain hasn't been used in decades, so that's probably a lost cause.
I've also had a good chat with a neighbour a couple of streets away who went through more or less the same thing. It seems that many of the downpipes in the area that extend below ground aren't joining up with the main surface water drains either! He now drains his downpipe into a raised bed in his (much smaller) front garden, via a water butt, which seems to work well for him. He tried speaking to council before doing the work but they didn't have a clue - there's no funding for expertise or enforcement of this kind of thing any more.
I think the main reason we don't seem to have had any significant problems from the awful drainage situation yet may be that my neighbour on that side has paved his front garden and right round the side of his double-fronted corner house . So our downpipe has a huge area of relatively dry earth to drain sideways into, starting just a few inches away.
This makes me more optimistic that I can safely keep draining our downpipe into the ground, as long as it's further from our wall.
Current plan:
Dig a sort of quasi French drain down the side of the garden bordering my neighour's paved area. I.e. a perforated pipe near the bottom of a shallow, pebble-filled trench. Perforated section to start 2m from the house. Perforated pipe to end in a slightly broader / deeper pebble-filled hole at bottom of garden. Hopefully the perforations will stop me getting one particular swampy patch. Add a water butt by the downpipe (to help water the front garden in the summer) and a new air brick on that side to help dry out any hidden sub-floor moisture penetration. The pebble-filled trench on the border of the garden should look quite smart too, as long as it doesn't overflow with water!
Am I being stupid?
I've actually got a structural engineer coming round tomorrow to look at something else (don't ask! :S) so will run this past him, particularly re any subsidence risk from altering the drainage situation.
The problem with (3) (other than legality!) is that the pavement doesn't have a handy slope on it, so I'll get a huge puddle outside the house. There's also an old cable TV connection point in the pavement right where the puddle would form, unless I extended the downpipe sideways as well as down the garden (which gets messy and harder to keep a consistent fall on it).
I tried following the pipe fragments through the garden but they disappear pretty quickly. I did unearth a very rusted, broken, 1m section of cast iron pipe that previously seems to have extended through my front wall, but that hole was plugged up a long time ago. Suggests to me that the theoretical connection to the main surface water drain hasn't been used in decades, so that's probably a lost cause.
I've also had a good chat with a neighbour a couple of streets away who went through more or less the same thing. It seems that many of the downpipes in the area that extend below ground aren't joining up with the main surface water drains either! He now drains his downpipe into a raised bed in his (much smaller) front garden, via a water butt, which seems to work well for him. He tried speaking to council before doing the work but they didn't have a clue - there's no funding for expertise or enforcement of this kind of thing any more.
I think the main reason we don't seem to have had any significant problems from the awful drainage situation yet may be that my neighbour on that side has paved his front garden and right round the side of his double-fronted corner house . So our downpipe has a huge area of relatively dry earth to drain sideways into, starting just a few inches away.
This makes me more optimistic that I can safely keep draining our downpipe into the ground, as long as it's further from our wall.
Current plan:
Dig a sort of quasi French drain down the side of the garden bordering my neighour's paved area. I.e. a perforated pipe near the bottom of a shallow, pebble-filled trench. Perforated section to start 2m from the house. Perforated pipe to end in a slightly broader / deeper pebble-filled hole at bottom of garden. Hopefully the perforations will stop me getting one particular swampy patch. Add a water butt by the downpipe (to help water the front garden in the summer) and a new air brick on that side to help dry out any hidden sub-floor moisture penetration. The pebble-filled trench on the border of the garden should look quite smart too, as long as it doesn't overflow with water!
Am I being stupid?
I've actually got a structural engineer coming round tomorrow to look at something else (don't ask! :S) so will run this past him, particularly re any subsidence risk from altering the drainage situation.
.