Project Site Flooding - Responsibility for surface water drainage during construction
Project Site Flooding - Responsibility for surface water drainage during construction
(OP)
Consider the following: A sloped 10 acre property that contains a 1 story commercial building. Owner chooses to add a wing onto the building which involves excavating into the hillside and stripping vegetation from the hillside to regrade it.
My question is, who would you expect to be responsible for designing surface water control systems during construction so that the building doesn't flood? And who/what would establish rainfall intensities these controls need to reasonably withstand?
Would this be formally designed by the civil engineer on the project? or would you expect the control system be the responsibility of the GC via a blanket requirement buried in the project specs?
My question is, who would you expect to be responsible for designing surface water control systems during construction so that the building doesn't flood? And who/what would establish rainfall intensities these controls need to reasonably withstand?
Would this be formally designed by the civil engineer on the project? or would you expect the control system be the responsibility of the GC via a blanket requirement buried in the project specs?
RE: Project Site Flooding - Responsibility for surface water drainage during construction
For a small project like yous the contractor just manages storm water as needed.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
The building flooded during a thunderstorm and the owner is only going after the contractor.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
RE: Project Site Flooding - Responsibility for surface water drainage during construction
In mine (which with regard to stormwater management is one of the most stringent areas in the US) SWMPs are designed and stamped by professional engineers without exception, for ANY project which involves disturbing dirt. Even if that project is as simple as replacing some existing landscaping which already has permanent stormwater runoff control measures in place, we are still required to engage an engineer to evaluate any possible change in the flows hitting the existing measures, and determining if additional temporary controls are needed.
I've worked in other jurisdictions were the general consensus was 'if you put silt fence in you are fine'.
But really, none of this is really pertinent to what you're asking. 'Stormwater' and 'Floodwater' are not the same thing. Stormwater controls in general don't prevent stormwater from flowing; they prevent that flowing water from moving sediment from a site to places where sediment should not be (off the site).
If, by grading the site a certain way, the contractor created a new path for runoff to overtop the foundation of the building, it would seem the contractor is on the hook. If the site experienced a 500 year rain event which would've cause the existing site to flood the building with runoff, and no flood water management was in place per the contractor's contract with the owner, then the contractor is likely going to be able to avoid liability.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
In my case, it seems highly misleading for a civil engineer to provide a Construction Implementation Plan which shows where to place hay bales, sandbags, and silt fences but then turn around when water comes into the building and say it was a "best effort" and blame the contractor.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
This is not just your jurisdiction - this is stormwater control in every jurisdiction. Stormwater management is about controlling sediment, so that you avoid contaminating water flows, surface waters, streams, and rivers - it has absolutely nothing to do with preventing damage to a structure from floodwater. Completely separate objectives, which need to be addressed with separate systems and planning.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
During construction, it's not normally a jurisdictional issue unless he tries to dump it where he shouldn't.
Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?
-Dik
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Stormwater plans generally don't address flooding.
We had a project a few years ago where it rained heavily after the Contractor pulled off the topsoil exposing a clay subsoil. The Contractor received a change order for the extra cost of removing swelling clay.
What is the wording of the construction contract?
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?
-Dik
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Bimr - but thats just bad luck for the contractor, no? Isnt it their responsibility to maintain a dry work space, such as only expose a certain area that you can seal/protect in the next day or two. If they want to expose everything they take the risk themselves.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?
-Dik
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Since there is absolutely nothing in writing stating what rainfall intensity the site would need to be designed for during construction, at what point does the issue transition to force majeure?
Like I mentioned, there were separate civil plans for "Sitework Implementation" and "Erosion and Sediment Control". The implementation plan showed locations of sandbags, hay bales, and silt fencing at the base of the hill, and which failed. It would seem to me that an implementation plan like this would be considered the stormwater management plan. It just seems unreasonable to expect a contractor to run an analysis on a sloped site to determine the level of temporary protection he'd need to install.
If it makes any difference, I dont see how the final grading plans would prevent water from coming into the building.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
They way you're describing this scenario makes it sound, to me, like the building would have flooded during this rain event even if the contractor had not yet touched the site. If that's true, and the contractor was not notified that surface water flow is an existing issue and they needed to mitigate it, then in my opinion there's no chance the contractor is going to absorb responsibility at the end of the day.
Failed how? Are you saying the silt fence was washed away or damaged by flowing water?
I would agree, that would probably be unreasonable - unless it was stipulated in the contract that surface water flow was a problem and that the contractor needed to control said surface water flow.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?
-Dik
RE: Project Site Flooding - Responsibility for surface water drainage during construction
The contractor has control over means and methods of construction. He can decide to handle the water or slop around in it during construction which will cost him time and money.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
OP has yet to provide enough detail to really know what happened here.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?
-Dik
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Normally I would agree with you that it's the GC's responsibility, but when it's a funky site and the CE seems to admit that it's a funky site by providing a construction implementation plan showing surface water controls to protect the existing portion of the building (just outside the bounds of excavation areas), dont you think that starts shifting the responsibility over to the CE? It certainly risks misleading the GC into thinking that if he places those controls he's good.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
The 'construction implementation plan' as you described in your second post- a drawing which shows the location of silt fence and maybe bales/wattles etc, is NOT a surface water control plan. Silt fence/bales/wattles DO NOT control surface water. They control sediment only. 'Stormwater', in the construction lexicon, does not mean 'controlling all water that may enter a site and preventing it from inundating excavations, flooding existing structures, or going places where it is generally not wanted'. 'Stormwater' means controlling sediment and pollution/contamination to the degree required by the AHJ. That's it.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
RE: Project Site Flooding - Responsibility for surface water drainage during construction
By definition, silt fence/hay bales/wattles do not control water. They are all fully water permeable, by design.
I can't explain why the civil engineer apparently put the SWMP in two places, but silt fence is not a floodwater control measure; anyone who saw that drawing and thought it would stop flooding is either inexperienced or inept.
RE: Project Site Flooding - Responsibility for surface water drainage during construction
www.PeirceEngineering.com
RE: Project Site Flooding - Responsibility for surface water drainage during construction
Contractor will not develop any plan unless it is required by the contract. so if the owner or designer is concerned about protecting the building from flooding (either during construction, or permanently after construction), than put a requirement in the contract drawings and specs to do that. temporary controls are generally designed by the contractors engineer, permanent controls should be designed by the owners engineer.