I’ve been thinking for a while … thinking about the sump plumbing. What do I need to connect to the sump, how should I connect it, and where should I connect it?
Sump plumbing should be relatively straightforward. So why did I have to think for a while? Because I also tried to build some future proofing into the system. Plus, I needed a seamless switch from the old repurposed grease trap to the new sump.
There is the water draining into the sump. We had the interior footing drains routed into the old grease trap. Those will now need to drain into the new sump. There also will be exterior footing drains that I need to connect to the pit.
I also have to pump the water out of the sump. That means re-routing the existing sump discharge into the sewer from the grease trap to the new sump pit.
It is typical to pump the sump water into the combined sewer system. But it is not ideal, because Chicago’s combined system barely copes as it is. Adding more water is best avoided and I have little interest in contributing to combined sewer overflow into the Chicago River or Lake Michigan. Plus the water draining from the footing drains into the sump is ground water, a valuable resource that I could use for irrigation.
At one point we will have a underground cistern in the back yard, which should be fed by the roof runoff. But I also could increase the size of the cistern and, in addition to the roof runoff, feed it with the sump water. That should provide me with a nice reliable water supply for irrigation.
To pump the water out of the sump into the future cistern, I need to rough in a discharge connection now. Once I activate that connection, I can cap the discharge into the sewer, or I can keep it, put the pump on a timer, and use it to flush the sewer once a day.
Why would I want to do that? It goes back to the check valve functionality issues we encountered. Our low flow fixtures don’t generate enough waste water volume or velocity to flush solids effectively past the check valve gate. Using the sump water at around 50 gallons per minute (gpm) to flush the system would alleviate that problem.
Last but not least, I need an electrical conduit through which I can route the sump pump power cords to an GFCI outlet on the basement wall.