Getting to Work on Tennessee Hollow
Restoration Begins on Presidio Watershed
California towhee at El Polin Spring in the Presidio.
Image courtesy the Presidio Trust.
In September 2008, an ambitious plan to improve the Presidio’s Tennessee Hollow watershed is getting underway.
At the crux of the plan is the restoration of a creek that runs from the famous El Polin Spring and two other springs to Crissy Field Marsh and the Bay. The creek, which currently runs underground through culverts and channels, will flow aboveground from hilltop to bay, and visitors will be able to walk a trail along the creek’s course. This is the same remarkable area Bay Nature covered in depth in our 2007 article Whispers in the Water.
Planners hope that access to the creek, as well as a restored historical identity in Tennessee Hollow, will create a revitalized and exciting space for the public to explore. The timeline for restoration extends over the next decade, but visitors can track visible changes and enjoy increasing access from the outset.
The Presidio Trust, a federal agency created to preserve the unique natural and historical character of the Presidio, is administering the project and wants to involve the public as much as possible. Plans to restore El Polín, the only named spring of the trio, and the eastern tributary are already complete, but volunteers can help make the plan happen.
If you want to get dirt under your fingernails, join the volunteer planting day on November 22. Volunteers will help bring toyon, wax myrtle, native grasses, and more to the landscape. Thirty-five thousand seedlings cultivated with the help of volunteers at the Presidio greenhouse have already been introduced to Tennessee Hollow, and thousands more will follow. The Presidio Trust hopes to have ongoing planting days on the fourth Saturday of every month.
Currently, the landscape of Tennessee Hollow is home to many nonnative species. Eucalyptus trees in particular soak up ground water that would otherwise drain down the hollow. Cypress and nonnative pines also draw from the water table and exclude native plants. Native trees and shrubs such as willow, coast live oak, and California buckeye are better suited to a healthy watershed.
In addition to native plant restoration, plans for the watershed call for the removal of several landfills. That will be a difficult task. Unknown toxins layer the ground in at least five locations, and one site has the confirmed presence of medical waste and cyanide dating from the 1950s.
This may seem dire, but landfill removal and native planting have already successfully restored a lower section of the creek at Thompson’s Reach. “We’ve seen some truly inspirational changes,” says Allison Stone, senior environmental planner at the trust.
Once the landscape is restored, more volunteers will be needed to help link native plants to the watershed’s rich past. “An ethnobotanical garden has been long discussed,” says Stone, and volunteer docents will be needed. “There will also be opportunities for helping to craft some of the interpretive messages,” Stone adds. The garden will showcase the native plants of the watershed and illuminate their historical uses.
The plans also provide for a boardwalk and interpretive signs to go around El Polín Loop. Tennessee Hollow’s history includes settlement by native people, Spanish garrisons, and Mexican ranchers, and more recently by the U.S. military. In 2003, archaeologists led by Stanford’s Barbara Voss discovered the foundation of an adobe structure near El Polín that probably was home to the noted Miramonte and Briones families in the 1800s. El Polín Spring was also the water source for a working well created by the military in the 1930s, and its streamlet was diverted into stone-lined channels. Planners intend to restore the well and channels to working order.
Plans for interpreting the historical significance of these structures are still evolving, says Stone, so volunteers will have a hand in shaping the final outcome. What’s more, plans for restoring the watershed’s lower regions and the western tributary, which runs through Pop Hicks Field, are still being developed and will be open to public comment.
Guided project tours at El Polín are open to the public on September 6 and 13, 2008. RSVP by calling (415) 561-5457 or emailing firstname.lastname@example.org. Maps are also available for self-guided tours for both adults and kids. You can download maps and read more about the project on the Presidio Trust website at www.presidio.gov/trust/projects/tenn.
To volunteer for the November 22 planting day, please call or email the volunteer coordinator at (415)561-5333 or email@example.com. If you’d like to receive updates about future planning and volunteer opportunities, email firstname.lastname@example.org and ask to be put on the Tennessee Hollow email update list.