Question re: Drop Structure with Victaulic Piping

[IanMathers]

I have a question regarding vertical drops in a gravity sanitary manhole structure. We are designing an access vault for an arctic community (it encloses both water and sewer lines) for a building where the sanitary service lines drop about 3 m vertically into the outlet drain. All the piping is 200 mm Victaulic, that is, there is no open benching and a sealed cleanout on the sewer. I advised one of the techs to draft it as illustrated in the upper photos with the vertical drop through a 45 degree elbow into a lateral placed vertically, directed toward the outlet. My director doesn't agree and wants it reconfigured as shown in the lower photos with the vertical drop into a 90 degree elbow and from there into the lateral placed horizontally. If there is no open benching, why would it be necessary to construct a typical drop manhole structure? One of the considerations is that the dimensions of the vault would have to be increased to accommodate the additional width for this parts arrangement, making the entire structure more costly. Is there anything technically wrong with the layout in the top photos?

 

[pennpiper]

IanMathers,
Your question: Is there anything technically wrong with the layout in the top photos?

My answer: Based on your description of the situation, I say there is nothing wrong with your arrangement (i.e.:the top picture).

Sometimes its possible to do all the right things and still get bad results

 

[IanMathers]

thank you pennpiper. very much appreciated.