Project Manager Brad Liljequist chronicles the building of the zHome, a ten-unit townhome in Issaquah, Washington—the first multifamily zero-energy community in the United States. Part 4: A new approach to stormwater management.
Water and salmon are iconic in the maritime Northwest. The Puget Sound basin has for decades been a hub of innovation in stormwater management, with a goal of protecting these icons. Recently, a movement has been afoot to change how stormwater is managed. In past years, stormwater for new development was typically collected in large vaults or ponds and then released at a set rate into local streams and lakes. While this strategy has had success in reducing impact to local water bodies, it requires large infrastructure, and also is not always effective in limiting runoff impacts.
zHome embodies a new stormwater management strategy called "low impact development," which takes a more site-driven approach, where water is detained and returned to the ground right on site. Our stormwater benchmark requires that the same amount of rainfall be reintroduced to the ground as fell there in the site’s original forested state. We employed a number of strategies to achieve this.
zHome also has been "Salmon-Safe certified," the first residential project in Washington State to achieve this standard. Salmon-Safe’s mission is to "transform land management practices so Pacific salmon can thrive in West Coast watersheds." This independent certification ensures that zHome’s stormwater and landscape management systems are ecologically sound and safe to aquatic resources. Click through the slideshow to learn more about zHome's strategy, and click here to watch a video about the cachement system.