"SimonRL" wrote

The basement is flooding because there is a drain that is connected to
what I assume is a sewer line and it backed up due to extremely heavy
rainfalls.

This needs to be fixed before anything else then. It may be pretty simple
like a pump above it.

In regards to identifying it, my landlord was trying to convince me
that it wasn't mold and that mold couldn't grow so quickly. I thought
she was wrong, but I couldn't say for sure.

It's mold for sure and it can grow pretty fast, but that has the look of a
longer embedded one into the wall that had a hasty clean up, probably
painted over as well, before rental.

Before you panic, in some areas this is really common and folks do not get
'sick all the time' from it. It just depends on how damp your area is.
I've seen the green sort many times and it's not the one to worry about
(although it will damage wood in time). It's the black fan shaped stuff you
need to worry about as potentially that can make some people sick.

The floor looked to be packed earth to me? That means it's going to be a
bit damp as there's no vapor barrier. Normally not so damp as to make mold,
but can happen in a wetter than normal seasons for their area. (Truely wet
places dont have dirt packed floored basements BTW).

If I'm wrong due to the pictures not being that detailed enough to be sure,
tell me what the floor looks like? Is it concrete with little hairline
cracks? Easy fix if so (have to be truely hairline).

Please realize that a newsgroup is just a collection of people and you can
get excellent, middling, and horrible advice ;-)

Don't assume the rental laws of your area, mean the landlord has to fix it,
or will be forced to. That varies by area. The only thing fairly certain
is in the USA (not sure you are posting from USA or not), you can break a
lease over this and get your deposit back for early termination if the mold
isn't addressed and you have medical issues that are potentially affected by
molds. You may have to go to a small claims court, but you'll win (get a
few more detailed close ups if planning that and save all your pics). In
the meantime, knowing your area will help to address the situation.

For example, if this was a rental house in Norfolk area, (It wouldnt be
unless north of it due to having a basement muchless what appears to be a
dirt floor one), the landlord isnt obligated to fix it but has to let you
terminate lease early and give you back your deposit (minus any other
damages you may have caused but nothing frivolous to add up to your deposit
or you can beat them in small claims easily). If you are in Boston, or
upper NY state etc, rules probably vary. To what extent, I do not know.
It's been my experience that most packed dirt floor basements (root cellers
originally in older houses) are fairly far north (snows every year and
sticks) or the dryer parts of the mid-west.

Addressing the mold for now- Spray bottle with bleach and water,
dehumidifier. Pray for no more rain until you can get the drain dealt with.
It sounds like you need a basement pump? Not familiar with those really.