Joint Sustainability Committee update: low-carbon concrete pilot lessons and urban-forest goals presented to commission

The Water and Wastewater Commission on Jan. 15 received an update from the Joint Sustainability Committee (JSC) on low-carbon concrete pilot programs and Austin’s urban-forest planning.

The JSC presentation reviewed Portland, Oregon’s experience launching a low-carbon concrete program. Commissioners were told Portland’s pilots showed embodied-carbon reductions of roughly 23%–50% compared with a 100% cement mix in pilot projects, but that achieving consistent low-carbon mixes requires supplier engagement and testing because admixtures and mix designs vary among regional concrete producers.

Commissioners also heard from Emily King, Austin’s urban forester, who summarized tree-survey data and canopy goals. King reported Austin’s current tree canopy is about 41% citywide and that the Austin Climate Equity Plan sets a goal of 50% canopy coverage by 2050. To reach that goal, staff estimated roughly 39,000 acres would need to be forested or reforested. King cited Texas A&M Forest Service survey methods and said the estimated compensatory ecosystem-service value of trees in Austin is about $12.4 billion, reflecting benefits such as heat mitigation and stormwater reduction.

The presentation noted efforts to target canopy improvements equitably; the Urban Forestry Replenishment Fund supports grants for community planting projects and partners such as TreeFolks were identified as typical grant recipients. Commissioners discussed implementation concerns including supply-chain readiness for low-carbon cement, testing and inspection needs at both supplier and project levels, and structural suitability of low-carbon mixes for different project types.

Separately, Commissioner Moriarty requested a future briefing on Austin Water’s approach to new state-level funding being discussed in the Texas Legislature (referred to in the meeting as the Texas Water Fund) and urged creation of a strategy to pursue an allocation from the fund; the commissioner cited an approximate figure of $6 billion being discussed at the legislature. Staff also reported outreach to newly sworn council members and noted a council member from District 6 may request a “state of the utility” briefing for her office or the commission.

Commissioners framed both topics as long-term efforts: Portland’s low-carbon program took several years of supplier coordination and pilots before broader adoption; Austin staff and the JSC noted similar multi-year steps would be needed to scale low-carbon concrete use for city construction projects.