My question isn't a common one so i needed to post it but I didn't know where.  

A few days ago I had a friend over to help me grind some stumps the stumps where about five feet from the pool so my friend is running the grinder because I had back surgery and was healing.
So i told my friend not to point the grinder towards the pool so that we wouldn't  get any dirt in the pool , well when I cam in the house to get us some Ice water I looked up and he was shooting dirt straight into the pool so I went out and said Dave what are you doing you just put a ton of dirt into the pool.   My question is I have been trying to get  all of the dirt out of the pool I did manage to get most of it out but there is some that just wont go away, it's been three weeks since this all started.  So i was wondering if I closed of the skimmer would the bottom drain have enough suck-shun to run the pool, the reason I am asking I shut the skimmer half way off and my filter pressure dropped from 15 down to 4 that doesn't seam like a lot pressure to me and if I was to shut the skimmer all the way off I don't think that the filter gauge would register anything.   We keep brushing the dirt down toward the drain but I am thinking that my pool sweep keep's the dirt away from the drain, Plus I have just installed new filter cartridges in my pump.    I might add we had our pool remolded last year and they took out the old round drain and put in a long narrow one about 5 inches wide and 3 feet long they told me that it was a new law to do away with the round ones because small children could get caught for it. So it just makes me wonder if there is enough suck-sun in the bottom drain. I have an in-ground pool