Drainage Design

[bico1010]

I am currently working on an urban roadway widening project, which is about 3 miles long. I encountered a problem when designing drainage. The site is flat and constructing series of underground culverts is not feasible. Therefore, I came up with two alternatives:
• Raise the existing pavement and construct an earthen ditch along one side of the roadway
• Construct earth berm

However, these two designs will require additional ROW. Can anyone suggest a drainage system with less impact? Thanks for the help.

 

[RWF7437]

bico1010,

This is a widening of an EXISTING road ? How is this roadway and right of way drained now ? If there are existing culverts, why can't they be extended ? If there are no culverts, only ditches along the alignment, why can't they be relocated along, and parallel to, the widened section ?

Good luck

 

[cvg]

constructing a berm may not be a feasible approach, since this could cause ponding on adjacent property.

 

[LCruiser]

How much drainage is there across the road now, cfs and culverts?

 

[bico1010]

There are no existing culverts, and the flow is about 1000cfs.

 

[RWF7437]

Unbelievable ! 1000 cfs drains along or across this road, or both. Where does it go now ? Does it just disappear into the earth ? Does it flow over the road uncontrolled ? Doesn't this create a problem for traffic? If ther is no traffic why on earth does it need widening ?

Enlighten us, PLEASE.

 

[cvg]

hopefully the 1,000 cfs is not in one location but in several along the 3 miles. Is this 100-year flow?

 

[LCruiser]

This 1,000 cfs is projected 1% or so flow I presume. The grade of the three miles is flat? What will be damaged by ponding? What is the traffic count? Lots of potential solutions, depending on the particulars.