WHAT IS THE GRAVEL BAR?
The gravel bar is an accumulation of debris and silty
sediment in what was once known as the deep end of the
pool behind the downstream dam. The debris ranges from
pebbles to softball sized stones to boulders bigger than
WHERE DID THE GRAVEL BAR COME FROM?
Barton Springs sits at the downstream end of a 115 sq mile
river drainage whose natural course carries water and debris
into the river. The dams built to create Barton Springs also
created a barrier that traps debris from every large flood
(those that top the upstream dam of the pool). The current
gravel bar is an accumulation of almost 20 years of debris.
HOW DOES THE GRAVEL BAR AFFECT THE WATER QUALITY OF THE POOL?
The flood debris traps an extraordinary amount of sediment
in the pool which is easily disturbed by swimmers and
bathers which in turn makes the water more murky more
DOES THE GRAVEL BAR AFFECT THE FLOW OF WATER IN THE POOL?
Flow in Barton Springs is determined by the output of the
springs. However, the gravel bar impedes the natural flow of
the pool as it has completely filled in the original creekbed
channel. If left unattended, the accumulating debris would
eventually convert our swimming pool into a wading pool. Continue reading “FAQs regarding the Gravel Bar”
The second decade of the 21st century will be getting off to a great start for the planet, the pool and people who love Barton Springs as the City of Austin plans to put in plenty of new trees to spruce up the springs beginning in January. With funding from the city and APF, Austin PARD is currently acquiring 80 trees averaging 45 gallons or larger to kick off the first wave of tree planting. Those are some big young trees! The Forestry department will need lots of help to make sure these trees find their new home comfortable enough to settle into for the next century or so. So, we are looking for you who want to steward the trees, new and old (everybody needs TLC). FBSP is looking for volunteers to spend one (or one half or one quarter) Saturday in January to put down the roots for several generations
of poolside pleasure!
Reference: Barton Springs Pool gravel bar must be removed.
We write to support the city staff’s plan to remove the gravel bar from Barton Springs Pool. The gravel bar is a large collection of flood debris (1500 cubic yards of gravel and boulders, and growing) that is spread over the downstream portion of the pool. The Barton Springs Pool Master Plan, which was developed to end decades of neglect at the pool, rightly calls for removing the gravel bar.
Removing the gravel bar is part of an overall effort to restore the pool to a more natural state. In a natural free-flowing creek, the flood debris would be washed down the creek. Instead, the dam that forms Barton Springs Pool traps the flood debris, and the flood debris acts as a second dam, trapping more flood debris.
The attention on the pool is bringing new members into FBSP. Several new members have joined into the FBSP Advocacy Committee. Committee members have been attending and speaking out in support of pool improvements and implementing the Master Plan projects. The Committee is also staying in contact with key staff of the City be abreast of emerging issues. Through all this participation, the Friends are building a stronger technical understanding of the difficult decisions the City faces. Among these tough issues are how to deal with the deterioration of the Barton Springs Pool bypass tunnel and how to maintain and restore the trees and canopy over the pool.
Since May, the Advocacy Committee has voiced the Friend’s mission at monthly meetings of the Parks & Recreation Board / Environmental Board Joint Committee that oversees the BSP Master Plan implementation. We requested the City work closely with our organization and others to end the neglect of the trees and to take positive actions. We announced a Tree Stewards Program the FBSP formulated with other volunteers from several organizations including TreeFolks and Austin Parks Foundation (APF). At the Joint Committee meetings and in meetings with our elected officials and City staff, we continue to press for implementation of all the Master Plan projects. All these efforts are slowly paying off. For example, through the combination of volunteer effort and donated funds, grants received by APF, and City funding, improved tree maintenance and new tree plantings will occur at BSP. Continue reading “Update from the Advocacy Committee”
The City of Austin Watershed Protection Department has been busy evaluating the Bypass Tunnel (BT) repair/construction options. So far around $100k has been spent researching different options to prevent continued deterioration and extend the life of or replace the thirty-four year old structure. The original assessment included three options, namely repair, modification, and complete replacement of the BT. The three main categories have been expanded with sub-options, namely 1., 1a., 1b (Stabilization), 2, 2a (Pipe-in-a-Pipe), and 3 (complete replacement), with the addition of two options, namely Piers and Other Options. All of these options were presented to the Environmental Board on August 19 by Mr. David Johns of the COA Watershed Protection Department. He was so kind as to furnish the slides depicting the various cross sections of the various options. These slides can be found on our website. As you review the slides, keep in mind that they generally are arranged from the least expensive to the most expensive. At this point, everyone has their own opinion as to the best option, depending on which considerations are valued at that moment, considerations being pool closure time, cost, flow capacity, endangered species, longevity, site disturbance, and constructability.
Option 1, the least expensive, least intrusive, and probably the least durable, is Stabilization. It adds a floor to the existing structure to stop the leaks in the bottom, add strength and weight, as well as side slope control. Option 1a lines the inside of the BT and includes poolside and side slope stability components. Option 1b adds even more ballast inside the BT and replaces the lost capacity of the BT with a sidewalk which doubles as an overflow ditch during floods, with a wall on the poolside. The advantage of options 1 is the cost. If funding is limited, better this than nothing. The minus is that you continue to maintain an older structure with unpredictable problems in the future, failing joints, new holes, who knows.