Dredger01
Civil/Environmental
- Oct 10, 2016
- 5
I've got a project where the outflow storm line (24") is draining a 2 acre commercial site. The contractors uncovered an existing water main that is conflict with the storm drain.
The City will not allow this waterline to be adjusted around the storm pipe. Unfortunately there is not another viable option for the site storm connection.
My thought is to install an inverted siphon under the water main. Basically have the 24-inch pipe duck under the existing waterline, then connect into the City curb inlet(discharge point).
Has anyone designed one of these before. I plan on installing an access MH just upstream of the waterline crossing. I'm not sure what hydraulic losses I might consider for such a system. The HGL of the site system should create enough pressure get through the siphon and into the point of connection.
I thought it might also be practical to install a second bypass line over the waterline for good measure.
Understandably that when the storm surge is over, there will be some residual water left in the pipe, like a grease trap in a house. In this part of the country, the soils are mostly clay, so infiltration of residual water might not work to well. In other words, we might have to live with that portion of the siphon holding some water.
Any thoughts or ideas? Much appreciated.
The City will not allow this waterline to be adjusted around the storm pipe. Unfortunately there is not another viable option for the site storm connection.
My thought is to install an inverted siphon under the water main. Basically have the 24-inch pipe duck under the existing waterline, then connect into the City curb inlet(discharge point).
Has anyone designed one of these before. I plan on installing an access MH just upstream of the waterline crossing. I'm not sure what hydraulic losses I might consider for such a system. The HGL of the site system should create enough pressure get through the siphon and into the point of connection.
I thought it might also be practical to install a second bypass line over the waterline for good measure.
Understandably that when the storm surge is over, there will be some residual water left in the pipe, like a grease trap in a house. In this part of the country, the soils are mostly clay, so infiltration of residual water might not work to well. In other words, we might have to live with that portion of the siphon holding some water.
Any thoughts or ideas? Much appreciated.