What kind of sump do I need to collect run off in my garden?

I have a small garden in San Francisco. When it rains the water all pools in the lowest part which happens to be near our building. I'd like to collect the water and pump in back into the garden. I may even dig a little gutter that would make a nice stream and keep the water away from the paths. The question is this: How do I keep mud from collecting in the sump?

What kind of sump do I need to collect run off in my garden?
Most sump pumps are designed to handle a little mud. Worst case scenario, it plugs. All you need to do is rinse it out with a hose. RScott