Understanding water distribution and local water

Housing unit design and layout that would work for a 2-3 people layout

defining what is acceptable for human needs

to design a toolkit, for more holistic water systems specifically on site




creating a building that is accepting change and a proponent for future endeavors


Understanding of immediate water:

“local” water:

water that is in immediate location. Local water can be various factors depending on the context. Portland, in this case has the ability and great strength to find water in close proximity, as it stands currently that water is in a aqueduct just outside of the city.


Our desire for local water found in research is considered immediate water, which in this case is water that fall directly onto the building platform via rain and is then filter and usable.


Living Building Challenge: Water

harvesting on site for the given needs while still respecting the natural hydrology 

water can be used, then purified and then used again

learning to challenge possibly outdated rules and codes to teach and educate that properly         regulated water on site is possible

All stormwater and water recharge must be treated on site

    stormwater can be released into neighboring sites with conditions


Rules of thumb

Typical family size: 3.2 people

per capita building use

Multi family- 40 gallons (per resident)

Water conserving toilets: 3 gal/flush

Low consumption toilets: 1.6 gal

Waterless toilets


Needs in a typical home:






    Can be shared




        Do you save more without a dishwasher or with one?


Water distribution

    Static pressure

    Upfeed distribution

    Downfeed distribution

    Tall building downfeed distribution


Amount that can be recycled

13.78 gallons a day:

Shower (7 minutes, 1.5 gpm): 10.5 gallons

Laundry: 1 gallon

Handwash dishes: .28 gallons

Other: 2 gallons


Assumptions that are being made

Residential 720sqft

Multi story

12 units per floor

1st floor is collection/harvesting

Water circuits, deploying space

20% circulation (12,500 workable space)



V1 0% being recycled

V2 50% being recycled

V3 highest % being recycled


    Possibilities for recycle





        Thermal Mass

Greywater to a level that is more that just toilets


Version from MEEB (redone)


15,625 * 43.5 (regular year) * .623 = 423,445 gallons can be harvested

5 stories residential/1st floor collection

12 units


60 units * 2.3 = 138 people

138 * 40gpd = 5,520 * 365 = 2,014,800 annual need for 40 gallons per day


Version backwards, as how much water can be used by collection only

*aka my own rules


5 stories (6 with first floor collection)

138 people * n * 365 days = 423,445 g/year

n = 423,445 g/year = 8.4 gal/ day



4 stories (5 with first floor collection)

110 people * n * 365 = 423,445 g/year

n = 423,445 g/year = 10.5 gal/day


Biggest water hoarders

Laundry and Showers


What can we recycle and use greywater for? That are very obvious


Washing Machine


So if we take out those two factors

and someones daily allowance is 8.4 gallons

We are accounting for what they could use is 7 a day and leaves some wiggle room


Is that possible?



1,160 possible capture

1,521 for 4 floors = 76% captured

1,900 for 5 floors = 61% captured


Therefore we need to recycle AT LEAST: 24-39% recycled for our water, THIS IS POSSIBLE


315,459 should try to be recycled in order to have a comfortable means for living

    ** very comfortable means of living


138 residents, with 5 floors of 12 units


Available vs. Singular

Available is the amount of water that can be recycled within normal jurisdiction, which is laundry and from hand washing, or diverting shower water to toilet use.


Singular water is water that can be recycled altogether which would include kitchen and shower water.


Avaliable per day to save: 2.28 gallons

Singular saving: 10.5 gallons

    Assumption: We can have a deep enough cleansing process that can recycle shower water, this is one of the more difficult challenges, seeing that normally this is not considered grey water


2.28 gallons per person per day— which is 16.78% of water recycled

If we recycle even 8 gallons of shower water— we will reach our goal


13.78 * 2.3 people = 32 gallons

32 * 12 units = 380 gallons per floor

380 * 4 floors = 1,521 gallons per day total NEEDED

380 * 5 floors = 1,900 gallons per day total NEEDED


Recycling capability



2.28 gallons recycled per day per person

2.3 people/unit * 2.28 = 5.24 gallons per day

5.24 gpd * 12 units/floor = 62.92 gallons


62.92 gallons * 4 floors (v1) = 251.71 gallons

62.92 gallons * 5 floors (v2) = 314.6 gallons


This exercise gives a reference of if we recycle what is possible in jurisdiction (avaliable) we fall a little short. Hopefully this can begin to create a conversation of more aggressive recycling systems but also a way to provide municipal opportunities to recycle shower water for more efficient use and sustainable buildings.



2.28 gallons + 8 gallons of shower water (per unit)

2.3 people/unit * 10.28 = 23.6 gallons per day

23.6 gpd * 12 units/floor = 283.73 gallons


283.73 gallons * 4 floors (v1) = 1,135 gallons

283.73 gallons * 5 floors (v2) = 1,419 gallons


If we capture rainwater, and store it, the amount being recycled is adequate for daily use and possibly giving back to the grid.


Catchment capability

making the assumption of just a one floor need


entire site size- 15,625 sq.ft

average annual rainfall- 43.5 in

dry season average (2/3)- 29 in

.623 conversation- as stated by Texas A&M site


15,625 * 29 in (dry year) * .623 = 253,093 gallons can be harvested

15,625 * 43.5 (regular year) * .623 = 423,445 gallons can be harvested

annual gallons needed- 503,700 (1st floor)


Dry season cistern size


1,380 gpd * 90 dry days = 124,200


124,200/7.48 in = 16,604^3 to gallons 124,206 gallon cistern


125,000 gallons cistern would be a typical size to meet gpd need


Challenging the sources

Philadelphia Government

    101.5 gallons per day


    80-100 gallons per day

    A toilet alone can use 27%

California Single Family Water Study

    173 gallons per household per day


    44-47% of people use grey water saving tools

    Allows others to get a license to that they can harvest storm water

    Since their drought people use 41 gallons per day, interesting





Large Questions

How do you empower residents to save water? without the monetary incentive? Advocacy for our hydrology. 


Home owners association for urban living buildings? Do we educate others on saving water to bring them to the advocacy for the public, do they get a certificate? “I lived in a passive hydro house for two years, and this is what I know”


If they pay for their water separately? and knowing that they will save? What if they don’t pay for it?


Would a dry sauna be worth it for the winter season? * connecting the fact that people shower longer


“If i had the money, I would pay to have longer showers” what if it was 300/month


Psychology of geography. Are they conscious on their own, or just by the need. Is it on the education system?





























































ashley kopetzky