itsnotrequired
09-05-2006, 12:32 PM
I have recently purchased a new home in Chicago and we had a very heavy rain last night. Water was pouring into our sump pit at such a tremendous rate that both the main and battery backup sump pumps were running just to keep up. It was unreal how much water was pouring into the pit. Some specifics of our setup:
- main pump is Zoeller 98-series cast iron (3600 GPH at 10' head)
- backup pump is Basement Watchdog Special battery powered (1750 GPH at 10' head)
- both pumps discharge to city sewer with in-line check valves (approx. 10' from pump intake to highest pipe point)
- both pumps rest on raised bricks in the pit (i.e. they are not resting on dirt)
- poured basement walls, basement floor roughly 9' below grade
- home and entire development is on level ground (i.e. not at the base of a hill or valley)
- 4" drain tile system around exterior and interior of foundation, empties into sump pit
- clay soil, no lawn installed yet
- downspout extenders installed to direct water away from home (flow toward street or to storm drain in back yard)
- houses adjacent to ours only 5 feet apart, same design as ours, have sump pits, gutters with downspout extenders and no lawns
This last storm totaled less than an inch of rain. Both pumps were running continuously for an hour and the main pump then ran continually for nearly another hour. It then ran intermittently for about another half hour. The water flowing in was brown with dissolved sediment or silt (no large particles like sand). I've dug around at the pump intakes and as near as I can tell, nothing is stuck in the intakes and reducing flow.
Based on the times and pumping capacity of the pumps, it appears as if I pumped nearly 10,000 gallons all told from this last storm. If an inch of rain is assumed (more than actually fell) and all the water was pumped (i.e. the ground absorbed nothing), then we're talking about an area of 126' x 126'. My whole lot is only 40' x 110'!
So what the heck is going on here? I understand a lawn will help with water shedding but this is ridiculous. Based on my numbers, it is as if I'm pumping all the water for me and my neighbors and then some. They have seen this water flowing into my pit and say that they never have flows that extreme. My thoughts:
1. My home is a few inches lower than the neighbors and thus a natural low spot.
2. Builder somehow tied neighbors drain tile into mine.
3. Catch basin for storm drain behind house is leaking and excess water is flowing into my drain tile system.
Anyone have any experience with massive flows such as this? Any other ideas?
- main pump is Zoeller 98-series cast iron (3600 GPH at 10' head)
- backup pump is Basement Watchdog Special battery powered (1750 GPH at 10' head)
- both pumps discharge to city sewer with in-line check valves (approx. 10' from pump intake to highest pipe point)
- both pumps rest on raised bricks in the pit (i.e. they are not resting on dirt)
- poured basement walls, basement floor roughly 9' below grade
- home and entire development is on level ground (i.e. not at the base of a hill or valley)
- 4" drain tile system around exterior and interior of foundation, empties into sump pit
- clay soil, no lawn installed yet
- downspout extenders installed to direct water away from home (flow toward street or to storm drain in back yard)
- houses adjacent to ours only 5 feet apart, same design as ours, have sump pits, gutters with downspout extenders and no lawns
This last storm totaled less than an inch of rain. Both pumps were running continuously for an hour and the main pump then ran continually for nearly another hour. It then ran intermittently for about another half hour. The water flowing in was brown with dissolved sediment or silt (no large particles like sand). I've dug around at the pump intakes and as near as I can tell, nothing is stuck in the intakes and reducing flow.
Based on the times and pumping capacity of the pumps, it appears as if I pumped nearly 10,000 gallons all told from this last storm. If an inch of rain is assumed (more than actually fell) and all the water was pumped (i.e. the ground absorbed nothing), then we're talking about an area of 126' x 126'. My whole lot is only 40' x 110'!
So what the heck is going on here? I understand a lawn will help with water shedding but this is ridiculous. Based on my numbers, it is as if I'm pumping all the water for me and my neighbors and then some. They have seen this water flowing into my pit and say that they never have flows that extreme. My thoughts:
1. My home is a few inches lower than the neighbors and thus a natural low spot.
2. Builder somehow tied neighbors drain tile into mine.
3. Catch basin for storm drain behind house is leaking and excess water is flowing into my drain tile system.
Anyone have any experience with massive flows such as this? Any other ideas?