Greetings!
We are working on the El Yunque National Forest Visitor's Center Renovation. El Yunque is the only U.S. national park that is in a tropical rainforest. This U.S. Forest Service facility was severely damaged in 2017 during Hurricane Maria. Our question has to do with the Visitor's Center water supply.
Because the facility is located in a rainforest - with an average annual rainfall of 120 inches - the USFS built a water collection and treatment system to provide water exclusively to the Visitor's Center and adjacent administrative building. Water is collected in a 4" gravity fed pipe from a small rainwater fed pool around 1/2 mile up-slope from the facility to a sediment filtration and treatment facility around midway, where it is stored in a 30,000 gallon cistern tank. From there, the water is fed to the project. The system is 100% gravity fed, and uses no electricity, and maintains around 50 psi.
So our question is - can the off-site rainwater harvesting system described above count as an alternative water source for Indoor Water Use Reduction, as it is a dedicated system that serves only the Visitor's Center facility and administrative buildings?
Thanks!
emily reese moody
Sustainability Director, Certifications & ComplianceJacobs
LEEDuser Expert
474 thumbs up
November 14, 2019 - 3:54 pm
Hi Vincent!
I have been to that visitor center, and also have a project replacing/repairing a facility damaged in the hurricane. We're working down in Salinas at the moment.
I see no issue with including the rainwater system in your calcs. It particularly should be fine since it serves only your buildings. I have had projects tap into municipally-supplied rainwater reuse systems that serve whole communities and it was fine. You should include a narrative with your calculations explaining the system; might not hurt to provide a site plan showing your project(s), the LEED boundary, and the location of the system.
Keep in mind that you cannot include the alternative source in the prerequisite calcs (the savings must be shown through the fixtures), but you can include them in the credit calcs for pursuing points. You'll need to provide a separate file from the WE calculator that LEED provides explaining your calculations and overall savings since there's no place for alternative sources in the provided calculator.
Vincent Pieri
PrincipalPieri Architects
2 thumbs up
November 14, 2019 - 4:17 pm
Hi Emily,
Thanks! My concern was that the harvested water is treated and is potable, but from your experience it appears that is not an issue. We will document the system as you suggest. Good luck with your project in Salinas!
emily reese moody
Sustainability Director, Certifications & ComplianceJacobs
LEEDuser Expert
474 thumbs up
November 16, 2019 - 11:55 pm
Ah, ok. I think that since you are starting with a nonpotable source versus a potable one such as a well, it should still qualify.
If you want a more official answer to be certain, you can email LEED Coach or GBCI and confirm. I tend to do this just as a safety.
Karen Joslin
Sustainability LeadPAE Consulting Engineers
5 thumbs up
January 27, 2020 - 5:23 pm
Piping up here to confirm our calculation strategy for using non-potable well water for ALL of the flush fixtures in a project. We get to 25%+ indoor water reduction through the fixture selections, no worries. By choosing the well water we are calculating nearly a 75% reduction of potable (municipal) water use. Confirming that we can do the straight replacement calculation along with the pre-req compliance calc for the points to show both results. Meaning we do not have to start counting the reduction after that first 20%, correct? ?
Gustavo De las Heras Izquierdo
LEED Expert184 thumbs up
January 29, 2020 - 9:08 am
Hi Pae,
I have never tried documenting well water as savings, but considering that the credit intent is to save water so that aquifers are preserved, I see very unlikely having your strategy accepted by the reviewer. Anyway, if you try it and your points are awarded, please let us know.
Karen Joslin
Sustainability LeadPAE Consulting Engineers
5 thumbs up
January 29, 2020 - 12:46 pm
The indoor water savings targets potable water to reduce the burden on municipal or local systems. Other alternative water includes specifically rainwater collected which if it is collected is not recharging any ground water sources until it exits after use, which is precisely what would happen to well sourced water. AT least her in the US...