Hi springfield 113.
Wow. If that is worms then i want your lawn. There is a lot of worm casts (from what i can see) but that is a good thing. As Mother Dove says the worms are suffering and are drowning in the soil. That is why the are coming to the top.
You need to sort your drainage out. (remember if you do get it sorted then you have to think, Where does the water go???
You might not think so but you have a very healthy lawn. (bar the saturated soil)
Sort the drainage out and watch where the water goes and then give me the recipe for your top dressing.
Your soil is perfect but It might be too compacted. you need to aerate it by taking plugs out and removing them. then fill the holes with river grit or sharp sand. Unfortunately you can't use the fork method as this will only compact the soil. ( well you can try and it will improve the drainage, but at some point you will have to take, some of your perfect lawn soil out and replace it with grit/sand for drainage.
Unfortunately again you will have to re-seed but there is no point until you sort the drainage out.
The only problem you have is that it is too wet.