Grade now, Pave later
Grade now, Pave later
(OP)
My municipality has a new 4-lane divided arterial project where we will grade now for the entire template, but only pave half of it & leave the final 2 lanes to complete in 15-20 years when the traffic demand warrrants it. This way, the right of way acquisition and rough grading is completed initially, making a fairly easy future completion. I wonder if other agencies have tried this approach, and specifically:
* Whether they constructed stormwater inlets & pipes initially for the future lanes
* How the future lane area was graded, drained, and maintained
* Any unforseen problems or benefits.
Thanks
* Whether they constructed stormwater inlets & pipes initially for the future lanes
* How the future lane area was graded, drained, and maintained
* Any unforseen problems or benefits.
Thanks





RE: Grade now, Pave later
RE: Grade now, Pave later
RE: Grade now, Pave later
Yes, we plan to tosoil and seed the future lane area. The grades are somewhat gentle, 4% max.
I was also trying to think of innovative uses for the future lane area, perhaps some LID stormwater treatements (grassed swale, etc) without messing up the subgrade under future pavement. Any other ideas?
RE: Grade now, Pave later
Grade from the center toward the outside. Pave the "outer" 2 lanes and let the unpaved lanes be a larger median. Then one should be able to place all storm (sized for completed project) and not need to install any when the additional inner lanes are added.
RE: Grade now, Pave later
RE: Grade now, Pave later
I was also considering a reverse crown approach, where the 2 pavements drain towards the center median. This would be beneficial for a number of reasons (saves inlets and pipe, etc) but I know this is not commonly done. My research shows a lot of municipalities not allowing reverse crown streets.
Has anyone had any experience with this?
It seems a natural fit for LID techniques, getting all that water onto a center median area which can be dealt with in a number of ways (planter beds, grassed swales, etc.)
Salt would be a problem here in MO, but I understand that as long as the drainage doesn't clog and water is flowing thru the system, salt will take care of itself.