Advice for a novice: Mold and water damage in basement
I own a 1920s Craftsman house in Kansas City, MO. It has an unfinished basement-garage, with a short driveway that slopes from street-level down to the garage door opening. Rain water sometimes comes into the basement under the garage door, but my sump pump typically pumps it out. However, this year was particularly rainy and the basement flooded several times.
Water in the basement has caused mold to grow throughout the basement, plus several concrete-like walls are slowly crumbling due to moisture content.
There's damage upstairs, too. Directly above the garage door, mold has come through the wall. And increased amounts of water in the ground and foundation have caused that side of the house to shift, putting cracks in the walls.
We have a dehumidifier; our insurance won't cover it because the cause is "ground water"; and we've even approached the city for assistance because their sewer drains are misplaced on our street (water rushes into our driveway just feet before the placement of a sewer drain; if the drain were on the other side, our basement would be fine).
We've taken care of the root problem by cleaning out sewer drains farther up the block, plus installed a new sump pump. But obviously we still have lots of carnage.
Most of what I se can be cleaned up with a household cleaner. Mix a 10% bleach solution and spray it on the mold. Go after it with a scrub brush, then rinse it. Dry it thoroughly. Looks like maybe you need to invest in a dehumidifier as well. As far as damage higher up the walls, you need to cure the leak as well as treating the resulting mold, otherwise you will be doing this over and over. If you don't get the root cause sorted out, you won't have to worry about mold. You won't have anything left for mold to grow on. Look for areas where water can penetrate. Roof leaks, bad caulk joints, etc.