Low spots=wet holes

[Mr.Ziffel]

Asked this in lawn care with only 1 response [thanks FIREMAN] so... I filled a low area [500 cu.yds]and seeded, now heavy rains show a few low spots, largest is 3-5' x 6-8' x 4-6" deep. Grass has come in great and even with standing water in low spots for 1.5-2 days until it drained looks good. I'm north of Seattle where grass can grow all year and this is a play/soccer field so I want it established over the winter. Question:

Should I completely fill low spots with sand/topsoil now, reseed and hope for germination, or

Partially fill with sand/topsoil, let grow through for a while, then do it again, repeat until level, or

Wait til late spring [when I can drive on it again] completely fill and level then re-seed or try to match with sod?
Thanks for suggestions, Will M.

[Guido]

I can't say for sure, but I'm 98% possitive that you should fill it and plant new grass seed or sod. I just think if you keep adding a little at a time and letting the grass grow through, the grass will be weaker. The shorter it is the less it has to feed upward which will let the grass use its nutrients to become more full instead of long. Know what I'm saying?

Fastest way to fix the problem too I think.

Hope this helps!