Pictures would help a tone. Have you tried rocks/stone?

I'll try to get a pic, it's been raining so I couldn't get it today.

Have no tried stone since its in the lawn a the area gets mowed over. Ideally I want something that grass grows through.

One problem we never talk about here is proper drainage. Oh wait, we talk about it all the time. The best thing you can do is remove the blockage timbers and allow the natural flow to take its course. Hate to say it but those timbers are in the wrong place. You are fortunate the water didn't back up into your basement. Now when you dismiss that idea, and the sand idea didn't work, then you are left with redirecting the flow around it by digging a swale.