Yep, two good spots on 380 are that big creek you cross around Navo. It's called Paloma Creek (aka Little Elm Creek). That's a good place to paddle or take a small boat. Good for catfish and crappie, some LMB.
Also there's the Greenbelt farther west just as you get to Denton. That's the Elm Fork of the Trinity River. Decent fishing there - especially good during the spring sand bass run. This is another good place to paddle if you're not too scared of snakes. The Greenbelt park has a canoe/kayak launch ramp, but you have to pay to use the park. Just across the hwy about 100 yds W of the park (on the S side) is a free place to park and walk down to the river. It used to be a road, but it's closed to traffic now. It's a pretty popular spot. Just park off the hwy and follow the road/trail straight to the water. Good luck.
The Greenbelt off 380 is still under water and closed. Last I checked, the whole Greenbelt was closed to paddlers and small boats until the water recedes. If you want to fish the Greenbelt, the best access is by Ray Roberts dam.