District 8 has one of the lowest levels of impervious cover of all the districts and the highest level of protected open space, including over 6,000 acres of the Balcones Canyonlands Preserve system and the Water Quality Protection Lands
Over 90 percent of the district lies within the Barton Springs Zone, the area that contributes recharge to the Edwards Aquifer and feeds Barton Springs. In addition to being one of the most popular attractions in Central Texas, Barton Springs is home to two endangered species — the Barton Springs Salamander and the Austin Blind Salamander. The Edwards Aquifer also provides the sole source of drinking water for 60,000 people on wells in this area.
In the recharge zone, there is little soil to filter out pollutants before water enters the aquifer. Water moves rapidly underground, re-emerging at Barton Springs within days or even hours. This means the water quality of the aquifer and Barton Springs is directly tied to development impacts and surface water pollution in the rest of the Barton Springs Zone, most of which is outside Austin’s jurisdiction. The environmental sensitivity of the aquifer and Barton Springs has made water quality a critical focus in the Barton Springs Zone for decades, culminating in voter approval of the Save Our Springs Initiative in 1992.
Some of the older neighborhoods along Ben White are identified as high priorities for both creek and localized flooding. Major clusters of drainage complaints are shown in blue and high priority flooded structures and roadways are shown in red on the map to the right.
The Watershed Protection Department addresses drainage and environmental problems using a three-tiered approach of capital improvement projects, programs, and regulations. Examples of these strategies in District 8 include:
- Capital Improvement Projects: Watershed Protection has completed numerous projects in this district, including multiple regional stormwater ponds, storm drain upgrades in the Williamson Creek watershed, drainage improvements in the Scenic Brook neighborhood, a flood study of the Gaines Creek tributary, the upgrade of a low water crossing at Covered Bridge Drive, and repairs for the bypass culvert at Barton Springs Pool. Projects are planned for the next five years as well, including additional enhancement projects at Barton Springs Pool, water quality pond retrofit projects, improvements at the Blowing Sink Preserve, and storm drain upgrades in the Barton Creek watershed.
- Programs: An important program for this district is the acquisition of open space within the Barton Spring Zone, funded by voter-approved bonds in 1998, 2000, 2006, and 2012. The City and its partners purchase and maintain environmentally sensitive land to protect both the quantity and quality of water recharging the aquifer. Known collectively as the Water Quality Protection Lands, this system of City-owned land and conservation easements managed by the Austin Water Utility permanently protects over 28,000 acres, preserving 25 percent of the recharge zone. Another key program is the Groundwater Team, which traces the flow of water underground through dye testing, protects critical environmental features during development, and monitors and evaluates the water quality of groundwater as it springs to the surface. Monitoring water quality at Barton Springs is essential for assessing the cumulative impact of development on the entire Barton Springs Edwards Aquifer as well as for endangered species protection and preservation of the unique swimming site.
- Regulations: With the Barton and Williamson Creek Ordinances adopted in the early 1980s, regulations have been a key strategy in this district for over 30 years. The Save Our Springs Ordinance, adopted in 1992, is unique from the rest of the city in requiring that water quality controls reduce the pollutant load for a site to pre-development conditions. As an alternative for older sites, the redevelopment exception was added to the code in 2007 to allow the full redevelopment of a site’s existing impervious cover in exchange for the construction of on-site water quality controls and off-site land mitigation.
Photo of Bear Creek flowing through the Lower Avana tract in the southern portion of District 8. This tract was acquired in 2011 as part of the Water Quality Protection Lands.