My new best friend... the Leak Frog:
It's been raining pretty hard here over the last couple of days and when I went down stairs this morning I heard one of my Leak Frog alarms. I have three of them in my utility room... one by my furnace (near the chimney where I have had water issues in the past), one next to my SaniFlo pump, and one in my equipment closet.
While I took out about 10 gallons of water from the chimney clean outs with the shop vac, the water the made it into the basement actually came from the top of the foundation. The sealant I used on the concrete blocks seems to be holding the water back very well.
After long steady rains, splash back and water from the wet outer foundation has occasionally seeped in at the pressure treated sill. I think the siding doesn't hang down quite enough past the sheathing. When it drys out a bit, I will hit the area on the inside with some expanding foam. On the outside, I will see what I can do with some z-flashing and silicone.
This is the top of the foundation in the corner where the chimney, sill, and foundation all meet. You can see the water seeping through a bit. It then trickles down the wall and puddles on the floor near the furnace.
Same corner, but from the outside.
You can see the sheathing is getting pretty wet.