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Defined term or common usage for drainage to sump 1

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envtechadvisor

Civil/Environmental
May 7, 2015
4
What is the concensus of what one should call the water that drains to a sump or sumps in the subsurface levels of a office building or other structure (e.g., three levels of parking below a building)? If one's structure is below the water table and in an area with "normal" precipiation, the sources of the water would be infiltrating groundwater and infiltrating surface water from precip and downspouts (especially if the ground surface and building/landscaping design does not permit water to flow away from the building). Regardless, once that water is in the subsurface, and drains along the foundation walls and to the footings, and then to the sub slab drainage system leading to the sumps and sump pumps, what should one call it? Should it be called subsurface drainage, foundation drainage, drainage water, gravity-recovered water, gravity-recovered drainage, infiltrated water, sump-recovered water, what?
 
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IMHO, define the water by where it comes from. That is, water from downspouts, paved areas, etc. is "surface water runoff". Water collected that originates from below the water table is "ground water infiltration".

Check the language used in any permitting documents to make sure that the "names" you choose are consistent with the permitting intent. You don't want to create an administrative problem by arbitrarily choosing a name that is not addressed in the documents.

[idea]
[r2d2]
 
Good idea, but what if, as in my situation, there are multiple sources (e.g., surface water infiltration that makes it to foundation drains and eventually to the sump, and ground water infiltration to the same)? Actually, there are other sources of water that end up in one's sump (e.g., a building/maintenance eng. could come up with a few like condensate from HVAC and boiler blow down). So, I don't want to mischaracterize all the contributors by identifying one source. Since my ultimate concern is treating the sump water before permitted discharge, perhaps one should define it by its ultimate collection and discharge (e.g., sump effluent or similar)?
 
foundation drains should be separate and not connected to surface water drains. so any seepage picked up by a slotted or perforated foundation drain will be groundwater. you do not want to introduce any more water into the foundation from other sources.

surface water drains will pick up any water drained from roofs, parking areas and perhaps other things such as condensate, blow down etc. it will likely be contaminated with oil, sediment etc and will be a much higher volume and flow rate than the foundation drainage. it will not be conveyed in perforated pipes and generally would be passed through an oil water separator and then to a storm drain outfall.
 
You have more faith in the integrity of the building's "envelope" than I do as I expect some amount of surface water makes it under a building and to its sumps. Nonetheless, I understand your distinction and your points. Thanks for the advice!
 
Your examples of "Condensate from HVAC" and "Boiler Blowdown" sound good to me, as suggested, they accurately describe the source. Why would you need to "invent" new names? If you know the sources, just use the existing names and define the total inflow to the sump as a the summation of percentages of each source.

[idea]
[r2d2]
 
I should have prefaced the discussion by saying I am looking for an umbrella term for the purpose of a lease (defining Landlord's responsibility for managing, treating, and discharging any water in the sump). So, a percentage source breakdown as you suggest would probably be too cumbersome. Thanks anyway.
 
'... any and all inflow to the buildings drainage system'


Be careful about vague wording - remember through 'contra proferentem' if there is any vaguely worded clauses in a contract (can be interpreted in more than one way) it will always be ruled in favour of the person who did not author / present the contract.
 
no faith necessary, surface water which seeps into the ground is magically transformed into groundwater just as groundwater which seeps out of the ground (at a spring) is transformed back into surface water...

 
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