On Fri, 13 Jun 2008 15:31:48 +0000, Reno wrote:

dnoyeB wrote in
:

Clay is so fine it won't settle fast enough to stay out of pumps and
pipes. I installed my sump pipes with as much slope towards the outlet
as possible so they empty faster after each pump cycle. If you could
raise up the pipe inside the house and as far from the outlet as
possible you could get a bit of flushing action that may help.

Unless you have a very small capacity pump or a lot of bends (more than
two or three) then bigger pump won't help.

You could try to install some geotextile fabric around the inside of the
sump to see if it helps. You need as much filter flow area as you can
get to minimize plugging of the fabric. Make an inside sump pail about
an inch or two smaller than the sump out of some sort of screen material
- plastic is best to avoid galvanic action with pump steel. Tightly wrap
fabric around screen, drop screen into sump and pump into screen. You
must use the felt type fabric, NOT the woven type.

If you really want to try a cheap and quick fix - wrap the pump with
some heavy plastic window screen material, the type recommended for cat
and dog resistance and then wrap the screen with the fabric. Shape is
like a big sack to get most flow area. Tie it up around the discharge
pipe. Then just pull the wrapped up pump once in a while to check for
clay buildup on fabric and rinse if needed.

The fabris has a very high flow capacity when it is clean but you may
get flooding of basement if it plugs up with clay so you need to monitor
it and either replace or clean when required. If pipe is left plugged
then there is a risk of flooding from the existing setup as well. Either
way maintenance is required. Pump would overheat and burnout if flow was
restricted either on inlet side or outlet side. Inlet restriction is
worse for pumps.

Most risk of plugging is with highest inflows to sump so check it after
major storms plus on a regular schedule.

There may be some good news in that the amount of clay may reduce with
time. The situation within the ground may stabilize and reduce the
amount of clay contribution. You should do all of the usual yard
drainage improvements to reduce the volume of water infiltrating to the
sump. That would speed up stabilization. You can expect clay to
re-appear after severe storms so check for plugging of filter after all
bad storms even after problem seems to have disappeared for a few years.

As a possible idea - is there a potential source for the clay other than
the obvious drain tiles? There could be a leaky water line causing the
clay content. Is the sump pump running when it shouldn't be? Or more
often then it should? Is it running during periods of dry weather when
you wouldn't expect any water in the drain tiles? Is there a check valve
on the pump or in the discharge line near the pump? If not the reverse
flush from the line when the pump stops could be flashing clay from the
sump pit or surrounding material. Is there a floor to the sump or is it
sitting on bare soil? I've seen several sumps made from just a piece of
pipe standing upright.

The amount of clay deposition you describe seems huge - is yard drainage
really poor? Ground should slope well away from house in all directions
and all roof spouts directed well away.

I think there is just lots of water. Small stream runs next to my house.
Rainfall does not affect the frequency of the sump pump.

Also, I like to stir up the dirt in my pit and let it eject into the
backyard. It may be better for me to just keep snaking it...