I agree; check the information on the litter packaging. If it doesn't clump, it is likely suitable for municipal sewers but I'm not sure about septic systems. If it is a clumping style, I've been told you shouldn't put it down the toilet.
I have a litter locker. It is like an old style diaper genie. It has a bag inside. You scoop the litter box contents into the top of the container and pull the slide to drop it into the bottom. When it's full, you just lift the whole top of the genie, cut off the plastic, tie it shut and toss. You could do this every garbage day, although with two cats, mine seems to last for more than a week before I have to empty it.