Where to connect drain pipe
Where to connect drain pipe
(OP)
We are planning to construct a concrete secondary containment with a sump to drain out either rainwater or other liquid mix. In order to drain the liquid inside the containment, an inlet pipe will be connected at the sump directly either to an existing drainline pipe or to an existing concrete catch basin. My question is where should I connect the pipe? Should it be to the existing drainline pipe or to the existing concrete catch basin?





RE: Where to connect drain pipe
You should check with your local water board (or State Offices) for design requirements and permitting needs. In all liklihood, you will need to discharge the effluent into a sanitary sewer and not into a drainage system/course.
The waterboard (or State) will most likely require calculations a/o report, and other measures...such as a oil/water separator (or other BMP) prior to discharge.
I urge you to hire an experienced, civil PE that is insured.
RE: Where to connect drain pipe
RE: Where to connect drain pipe
Look at the regulatory stormwater manual's definition of what qualifies as an illict storm connection or discharge.
RE: Where to connect drain pipe
RE: Where to connect drain pipe
If you have less-than-desirable soils (rocky, organics, weak fill), and choose to intersect the existing storm line because there will be less trenching, then connect to the existing line, but do so with a manhole. Manholes can be ordered in prefabricated sections, or can be built in the field (block type). Manholes aren't very expensive, but will require additional construction time be undertaken as compared to the first option.
Placing a buried tee or wye is a risky idea. It's highly probable that you will get a clog at the intersection at some point in time....unless, you are 100% certain that your discharge is free of debris and sediments, install a manhole. Some engineers may argue that you can install a cleanout or rodding inlet, but it seems to me that spending a little more money for a manhole is smart-money spent.
You will need to perform a costing exercise to determine the best choice for the situation. In regards to cost data, I would first speak to a local, reputable contractor to determine his pre-profit cost. If you don't want to speak to a contractor, then RS Means is a popular publisher of cost data for construction. Beware: I've found their data to be inflated, laughable.
I hope this helps.
h.
RE: Where to connect drain pipe