19-0710 v3.X Water Scale Jumping Opportunities
For reference, the campus has many buildings with interconnected, winding paths of travel. our LBC project boundary is being carefully considered, as there aren't strict boundaries delineating each plot.
The LBC pursuits include one full certification (this project), and one Energy Petal certification project. Attached for reference is our latest landscape schematic. This project is on page 3, sheet L1.3.
For this project, we're facing some challenges with the local health department, and therefore we'd like to discuss opportunities for scale jumping, in order to ensure full LBC certification is still feasible. The project identifies as Transect L3.
We have championed the local municipality to utilize gray water as potable water, and black water as gray water for irrigation, and while we have additional communications in progress, it appears we must take the exception I05-E1 4/2010 (to utilize a municipal potable water supply for potable uses) as well as I05-e2 11/2012 (municipal potable water for fire protection), and subsequently I05-E6 3/2015 (connection to the municipal sewage system).
The public water supply does have chlorine, so our intent is to apply for I05-E3 7/2009 as well, and provide filtration media at the point of use. Per conversations with the health department, there is concern regarding allowing dechlorination, due to increased incidence of legionella; furthermore that legionella has now become airborne. This project includes residential units which may be vacant for months, which may allow legionella or other bacteria to grow in plumbing lines when water is not continuously discharged. We are reviewing solutions however it appears that we will need to discharge water regularly to flush the system of any potentially dangerous bacterial growth. Our question now includes: can this water which will be flushed for public health safety be removed from our total water consumption calculations? And if not, can we apply for an exception to the requirement to dechlorinate the potable water supply based on the public health department's requirements?
Our progress calculations for irrigation demand exceed the amount of water we will produce onsite by reclaiming gray water. The site will harvest some rain water, however the county mandate is that all collected rainwater must be used within 96 hours of capture. As the project is located in California (a drought state), we will not be able to guarantee a consistent irrigation water supply without also applying for I05-E9 4/2017 (Municipal Source Offset). We are still investigating if the project can harvest enough gray water to serve as a water supply for irrigation. Other strategies for scale jumping are outlined below:
Given the extent of the exceptions we must apply for, we'd like to confirm that this is still viable. Additionally, we'd like to suggest some scale jumping tactics for discussion. Below are ideas we're suggesting which could be applied separately or together for a larger strategy to support a net positive water strategy for the campus:
1. The sister project, registered for LBC Petal certification, is not seeking the water petal. It's being constructed on a previously developed site which currently sheds 100% of its rainfall to the storm drain. We'd like to suggest designing best practices in redevelopment, and capturing / diverting stormwater to the 85th percentile storm event. Unfortunately, that building isn't close enough to this project site to serve as a shared aquifer. However: Can this water savings be virtually applied towards our net positive water strategy, via I05-E8 4/2017 “Scale Jumping within an Aquifer”?
2. There are multiple existing buildings in this project campus which are not a part of this project's scope of work. We'd like to suggest replacing existing toilet fixtures and possibly lavatories throughout the campus, to conserve water consumption campus-wide. Can this water savings be virtually attributed towards our net positive water strategy?
3. There is existing landscape surrounding the building, served by existing irrigation lines. In some areas, the irrigation lines require minimal repair and reorientation to account for age and reoriented new building. Can this water demand be excluded and/or partially excluded from our water demand, provided we are consistent in defining our LBC project boundary? We would clearly communicate new scope, and sub-meter accordingly.
4b. We'd like to propose drilling a well onsite for use as either potable or non-potable water. Investigations on water quality are in process.
5. Purple Pipe. We understand the use of large scale public treatment facilities is not allowed. In this project's case, there is Purple Pipe provided and available about 1/4 mile away from this project. The client has indicated that if this water could be brought closer to the project, it would allow future projects greater access to a non-potable supply, opening the door to significant future water savings in other projects. Given the limitations of access to non-potable water for this project, we'd like to ask for an exception.
This alternative strategy is no longer being considered by the client.
4a. The building design consists two sister buildings sharing a central court yard. The footprint of these buildings are within +/-50' of each other. The occupants of both buildings use restrooms which are located in just one of the buildings. If necessary, we could reduce our LBC submittal to the building without the restrooms, in order to meet the intent of the water petal. We'd prefer to have this one project include both buildings, but in actuality, they can be considered two separate entities. Provided we can comply with all other imperatives, would this strategy be allowed and/or preferred to the above, in order to meet the net positive water requirements?
5. Connection to public sewer: It's our understanding that the AHJ will not allow us to retain blackwater on site for diversion. We are still in communication to champion and advocate for a black water system, however in the event they will not allow it: we'd like to ensure compliance with exception #I05-E63/2015. We're currently researching how the treatment plant operates, but need to understand how the balance of sewage going out, and water returning from the plant, is calculated. Any examples you can give regarding this exception are appreciated. update: This project is located in the County of Los Angeles. The neighboring county is Orange. We've had extensive conversations with the [city] wastewater treatment department; the District of Los Angeles wastewater department, as well as the Orange County wastewater department. All use chlorine and harsh chemicals to disinfect blackwater. We can clearly show this research and communication, however there is no opportunity to treat blackwater within 100 miles of the project site. We'd like to discuss any possible exceptions due to mandates by the public health department to connect to the municipal sewer
The flush water cannot be excluded from the project's water consumption calculations. However, since the local public health department would require daily system flushing in order to prevent legionella, this project may be exempt from the dechlorination requirements in order to conserve water. The chlorine added must be the minimum amount allowed by code.
1. Under version 4.0 of the Living Building Challenge, refueling of the aquifer may be considered a handprinting strategy that can be used to offset the project's sewer connection, since the other registered project is located within the same watershed.
2. Under version 4.0 of the Living Building Challenge, handprinting has been opened up as a pathway for demonstrating net positive water performance. If the team chooses to upgrade the water petal to version 4.0, then the project team could replace existing fixtures within the campus to contribute to the net positive water strategy.
3. The project area must remain consistent across all Imperatives, and must include all areas that are disturbed by the project work. If the project area includes the existing irrigation lines, then the water use expended from those lines within the project area needs to be accounted for in the project documentation. If the lines are just crossing the Project Area, and not releasing any water within it, that water does not need to be accounted for in the Project Area.
4b. If a well were to be drilled on-site, the team must demonstrate that it is not negatively impacting the local aquifer.
5. Purple pipe: Connecting the project to an existing purple pipe system would not warrant an exception, but it can be used as a scale jumping strategy.
5. Connection to public sewer: Under version 4.0 of the Living Building Challenge, projects that are not able to treat grey and black water on-site may connect to municipal systems, and use handprinting within the watershed or community in order to offset the municipal sewer connection. Note that there is no compliance pathway under LBC 3.1 that allows a sewer connection given the lack of nearby wastewater treatment utilities that meet the requirements of I05-E6 Municipal Sewage Connection. In order to move forward with meeting the Water Petal, the project team must upgrade to the 4.0 Water Petal, which creates a pathway for the team via handprinting. The team has already outlined two compliant handprinting strategies in questions 1 and 2 of their submittal.