Storm sewer location

[ALTIME]

Hello Everyone,

I'm wondering what are the pros and cons of placing the storm sewers under the road with catch basins on the sides versus storm sewers under gutter with catch basin manholes on the sewer side and catch basins on the other side.

any thoughts?

Thank you,

Altime

 

[cvg]

disadvantages are

long connector pipes from one side of the road to the other might require the mainline to be deeper

typically a lot of dry utilities such as phone, cable etc are placed near the gutter or sidewalk which can present a conflict for installation or maintenance of the storm drain

you shouldn't put manholes in the gutter

 

[civilperson]

Centerline of street is usually reserved for sanitary sewer.

 

[Drumchaser]

Altime

It is not a "preferred" practice to place storm sewer (or any other line) under the roadway.
Primary reasoning is that you have to handle traffic if it is done under live traffic conditions, then you have to backfill and patch the rdwy. and it is costly when you have to go down and fix something. If it is a new location, well this makes the installation easier but it is best not to place lines under the roadbed unless absolutely necessary.
If utility lines are placed under the road they should be inside a casing, for easy access, repair, removal etc. without tearing up the road.

It is a common practice to place cross drainage (RCP transverse to centerline of rdwy) if needed.
We generally place the stm swr just outside and parallel to the back of curb line, tying into the walls of our catch basins. We place cross drainage lines "selectively" as required.



Hope this is clear as mud (yours was)

 

[hydrae]

Where I am, the roads are typically divided up into 4 zones
water, storm, sewer, gas in that order with the water on the north and west sides. With dry pipes (phone, TV, power) are under the sidewalk or in the planter strip on both sides.

I have allways found it is easier to fix the road than some fancy plants or trees that get installed on the side of the road

Hydrae

 

[LCruiser]

As hydrea insinuates, there are sometimes standards in cities - e.g. sanitary sewer 10ft E or N of CL, Storm Drain on CL, Potable water 10 ft W or S of CL, elect 5' from curb, etc. Check with the public works depts of the nearest cities - it may be a regional thing which would be good. Follow that.

 

[655321]

One benefit to putting storm sewer on the outside of the pavement behind the curb is that, with the proper inlet, the bury depth can be reduced.

I also think that since storm sewer is generally shallow anyway, it may be good to keep them out of the road to reduce potential failure due to bad compaction.

I've worked in city's that have required storm sewers in the center of the road and behind the curb. I really prefer placing it behind the curb.

 

[LCruiser]

655321 -

There are indeed advantages to putting it behind a curb, but as has been pointed out it's a long reach from the other side. There is also frequently not enough room behind the curb, and it's not *always* shallow...