Barton Springs Public Process

The following was posted in bartonsprings@yahoogroups.com on 7/25/2010 by Laurie dot Dries at ci dot austin dot tx dot us:

The plants are a critical component of a healthy environment in the Springs. In fact, they are what has kept the floating nuisance algae at bay (currently less than 1% of the surface area of the water), and helped maintain the beautiful clear water we see now.  We have high discharge from the aquifer (~95 cfs), which in the past has been a time of murkier water because the flow would stir up the loose sediment and send it up into the water column. That combined with disturbance from us swimmers would decrease visibility to a couple of feet by evening’s end. However, since the plants have become established, the water is less murky because the root systems of the plants have captured sediment and keep it anchored to the substrate. Quite a contrast with the floating algae of 2006….The abundance of the plants is a beautiful reflection of the success of our efforts to nudge Barton Springs back toward a better, more resilient ecological condition, as it was once was decades ago.   Far more people have told me that they love the plants and don’t want any removed, than have complained to me.  Most swimmers that I have heard from prefer to swim in the deep channel not only to avoid emerging plants but also because the water current is less strong there. There is more than enough room for us to swim the length of Barton Springs and avoid plants; swimming in a straight line isn’t a requirement at Barton Springs, we don’t have lanes. Enjoy it.

That said, there is a plan for tending the plants, it’s just a good year and they are growing quickly.  We doing our best to keep up with their growth.   Actually, there are short- and long-term plans.  The short-term is trimming, trimming, trimming as often as we can. Barton Springs lifeguards are allowed to trim the columns of plants outside of salamander habitat as necessary.  Those plants in salamander habitat (the Beach and springs areas) are protected and must be tended by City of Austin staff listed on our USFWS permits, or under their direct supervision. The flexible plants whose columns bend in the flow of water need to be left alone (water stargrass, coontail, water primrose — stop by a check out the pretty little yellow flowers on some of them). They provide cover and food for salamander prey, and habitat for small fishes and aquatic insects.  They also tend not to have niusance green algae growing on them. The Salamander Conservation Program staff (Me, Liza, Mike, Todd) trim and manage these plants.  However, the vast majority of plants on the Beach are those with stiff, spiky stalks and leaves, with nuisance green algae around them.  This species, Sagittaria platyphylla, is native to this area, and it has spread like a virus in Barton Springs! So, this year, Barton Springs managers and lifeguards are also allowed to trim the stalks and leaves of these plants whenever they can.  Ultimately we will replace these plants with other species more suitable for the area.

This leads to the long-term plan for plants.  With the removal of the gravel bar, we could lose much of the plant life of the Springs unless we do something to counteract it. The plants on the gravel bar and on the Beach abutting that area will all have to be uprooted before the work area is isolated with a cofferdam and de-watered.  All of these except the Sagittaria are plants that we want to keep because they bend in the water flow, have small, isolated root balls, and don’t tend to have niusance algae captured within them. Instead of just losing these plants, My colleagues and I will be removing most of the plants and holding them in the water upstream.  Once most of the gravel is removed, we will use these plants to re-stock the area (a layer a gravel will be left on the limestone bottom for this). The exception is the Sagittaria.  Since this plant species is such a nuisance on the Beach and blocks flow, we will remove all of it there and re-stock with the other species of plants, some of which we already have in the Springs.

Here’s the cool part.  The Sagittaria plants are perfect native plants for bank stabilization and re-vegetation. So, those removed from Barton Springs will be used on other projects around the City, such as re-vegetation on Ladybird Lake.  This will save the cost of purchasing plants. This means there will be opportunities this fall to help uproot these plants. I will let you all know when you can help.

Ya’ll, let’s not forget that Barton Springs is a precious natural swimming hole, plants are part of that system. We humans didn’t create the springs, we share the springs with Nature. Plants in Barton Springs means life or death for a variety of wildlife; they are merely an inconvenience for us who swim around them.  Nature is dynamic, always changing. Now there is a great abundance of plants; in the future, floods will rip them out and carry them away. Anyone that doesn’t want to swim with Nature has numerous swimming pools all over Austin to choose from, where plants and other wildlife can be avoided.

Cheers,
Laurie

The note from Laurie prompted this response from Bill Bunch, a lawyer for the Save Our Springs Alliance, bill at sosalliance dot org.

Laurie,

Thank you so much for this summary and your observations.

I remain a bit concerned about labelling any of the native plants a
“nuisance,” although I understand the use of that word and that
perspective in light of how heavy the growth has become in some areas.
Certainly trimming and some removal makes sense — I’m just concerned
that we not go overboard.

I remain especially concerned about the dredging operation and how
revegetation will take place. If the bottom is scrapped, will a layer of
gravel provide sufficient substrate for plants to recolonize? Seems a
significant top layer should be cut and preserved and replaced, to the
greatest extent possible.

As you have described, the water quality and habitat benefits of the
plants far exceed any disruption to swimming.

Again, many thanks,
BillLaurie,

Thank you so much for this summary and your observations.

I remain a bit concerned about labelling any of the native plants a
“nuisance,” although I understand the use of that word and that
perspective in light of how heavy the growth has become in some areas.
Certainly trimming and some removal makes sense — I’m just concerned
that we not go overboard.

I remain especially concerned about the dredging operation and how
revegetation will take place. If the bottom is scrapped, will a layer of
gravel provide sufficient substrate for plants to recolonize? Seems a
significant top layer should be cut and preserved and replaced, to the
greatest extent possible.

As you have described, the water quality and habitat benefits of the
plants far exceed any disruption to swimming.

Again, many thanks,
Bill