River Sol hit a speed bump over the summer for its planned greywater irrigation system, causing a delay in starting construction until the issue could be resolved.
Owners Scott and Lisa May intended to treat River Sol’s greywater, which is water from household sinks and drains, then use it for subsurface irrigation of the many plants and trees planned around their home.
The greywater system doesn’t require discharge into the City of Bend’s wastewater system. The same is true for River Sol’s blackwater, which is water from toilets, that a separate system will treat onsite while converting solid waste to organic compost.
The state Department of Environmental Quality (DEQ), however, rejected the greywater irrigation plans because of the property’s uphill proximity to the Deschutes River and concerns about soil quality and its ability to filter and absorb the greywater. DEQ’s concern: Greywater will infiltrate the river. Rules also require properties within city limits to hook to municipal wastewater systems.
The Mays, however, are examining a system designed by Oregon-based Orenco that treats greywater to such a high level that they hope DEQ will approve the greywater irrigation.
The treated greywater would irrigate apple trees and myriad other native plants and trees onsite that provide food sources and attract pollinators.
If DEQ still objects, River Sol could apply to the International Living Future Institute (ILFI), which runs the Living Building Challenge, to change River Sol’s water requirement from Level 3.1 to 4.0, allowing the Mays to connect to the city’s wastewater lines and offset any wastewater discharged into those lines by supporting water savings elsewhere in the region. This is referred to as “handprinting.”
The Mays, however, prefer to treat all their wastewater under 3.1, and believe existing technology can satisfy DEQ, while also taking pressure of the city’s wastewater system.
The Mays in late July were considering more specific soil tests for their property to determine soil quality and perhaps alleviate DEQ’s concerns about the soil’s ability to absorb greywater and prevent it from reaching the river.
Another option for River Sol’s greywater could be to divert it to a greenhouse, where greywater would be consumed by plants, and eliminated through evaporation and transpiration. That would alleviate DEQ’s concerns over greywater in the soil. (How would plants/trees be watered outside the greenhouse??)
The Mays also have spoken with a consultant on an LBC project on Bainbridge Island, Washington, where a home above Puget Sound faced similar wastewater challenges. The Loom House, the first home to be certified LBC as a retrofit, received approval for a two-step septic system. That system first treats all wastewater in one tank, where solids drop out, then treats all leftover water in a second tank using a textile filter system. When the water leaves the second tank, it’s said to be cleaner than water treated in the municipal system and is used for Loom’s drip irrigation. That water is further cleaned by soil and plants as it seeps to the island’s aquifer, thus replenishing the island’s drinking water while reducing pressure on the island’s wastewater system — a win, win.
As of Aug. 1, the Mays were evaluating their greywater options, including talking with the Loom House’s water consultant, Biohabitats, in search for a resolution that would satisfy regulatory and LBC requirements, and allow a fall groundbreaking.