On 18 Apr 2007 05:12:37 -0700, chrisexv6 wrote:

Overbuilding is good

But I didnt want to go too crazy, in case something I add effects
something that is already there (i.e. draining the gutter runoff into
the same trench as the French drain....would the second pipe from the
gutter interfere with the operation of the french drain pipe).

The french drain pipe will be open to daylight, about 60' away, down a
hill. So I should get good gravity flow. I might be able to use the
berm idea for some of that 60' run, which would help keep the water
over the french drain area, and give it a chance to get out (in the
case of torrential downpours). The only question I have at this point
is if I should tap the gutters into the same pipe, run another pipe in
the same trench, or run a separate trench for the gutter pipe.

BTW, what depth are you suggesting for the french drain? I was
thinking 24" at its highest....with a pitch of 1/4" per foot, the
depth where it sees daylight would be about 40" or so. Could the
pitch be lowered to 1/8" per foot? I think I saw that suggested, but
again, overbuilding is better than underbuilding.

-Chris


well, you can use the same pipe for the landscape drain and
the downspout drain, as long as it's big enough. for both.
To figure that out, you could estimate the maximum amount of
water you expect to have to move per minute. Or you could just
go with a 30" culvert, so you've got a big enough pipe for
wild animals, and small children, and a weapons cache.

In any case, bury it deep enough to be below the frostline,
if any.

You'll want to build a spreader dam or rockfall or
something at the outflow, or it will
build you a nice gulley in a year or so.