Sunday, August 21, 2011

Windsufing South Pool

It was family fun on the water yesterday at Twin Buttes South Pool. Alvin,
Alan, Kristin, Medwin, Brandie, Micah and Naomi windsurfed light to moderate
winds. I posted pictures om Sailing San Angelo.

I wish I'd taken more, but I was either trying to remember how to rig or
enjoying time on the water. Medwin and Brandie took a number of pictures, which I trust are of higher quality.

The South Pool is the place for windsurfers and small sailboats, given the South Concho still flows. It's not enough to push water into the Equalization Channel and the North Pool, but it's the reason the South Pool is down 4 feet while the North is down 20 since early 2011.

The South Pool can be reached by taking Knickerbocker Road south past Lake Nasworthy, past the airport, then turning right toward the town of Knickerbocker. As you go over the dam, you'll see the equalization channel (EQ).  Turn left after crossing the bridge over the equalization channel.  You'll rattle over a cattle guard.

The road turns from asphalt to dirt at the dry EQ boat ramp. The dirt road can be relatively smooth or have major ruts.  As the city is installing pipe railing, the dirt road is in great shape.

Turn left at the next dirt road, don't cross the cattle guard. Drive until the brush opens up to reveal a nice sized body of water. The grade into the water is generally gentle and a South wind blows onshore, ideal conditions for beginning windsurfers.

It's fun having many sailors on the water. Hope to see you out soon.

Wednesday, August 17, 2011

Little Runoff for Twin Buttes

Twin Buttes Reservoir rose just over a half foot from recent rains, according to the Texas Water Development Board:

8-12-11 -- 1,894.82
8-16-11 -- 1,895.44

The Bureau of Reclamation painted a similar picture (see above).  I'm praying for more rain.

Friday, August 5, 2011

Down, Down, Down

Twin Buttes dropped ten feet since the last time I windsurfed.  It's on the way to levels seen from 2002-2004.  The long range forecasts shows a dry 2012.

Both boat ramps are dry.  Two people can be seen standing at the bottom of the main boat ramp on the north side of the North Pool.

The temporary, low water one is well out of the water.

It may be time to sail from the South pool, provided the city keeps access open and doesn't drain it. 

My shadow looks like a Chicken Farm Starkeeper by Roger Allen.  Is there a way to make it a Lake keeper?

Wednesday, August 3, 2011

Draining the South Pool

City Councilman Paul Alexander spoke to the Standard Times about moving water from the South Pool to Lake Nasworthy or the North Pool.  He didn't mention whether the 2.5 miles of South Concho River needed to get the water to Nasworthy had water in it.

It appears to be empty.  How much water would be lost to thirsty ground? Dry ground can dramatically reduce the amount of water making it to a retention area.

Based on a survey in 1994, about 35.2 acres of wetlands once existed below Twin Buttes Dam along the South Concho River.  Since 1994, reductions in flow from the Twin Buttes spillway, installation of seepage controls, and prolonged drought have eliminated all wetlands below the dam (see Figure 4.) As a result, all known, former wetlands have disappeared.

The South Pool is more like a bowl.  It doesn't have the varied bottom topography the North Pool does.  Did the City model the impact of moving water at current levels? 

Twin Buttes is a shallow reservoir (maximum depth of 42 feet at full conservation pool level. )
The boat ramp at the North Pool is high and dry. 

Additional water would would run to the west, north (toward the old Marina) and south toward the equalization channel.  Paul Alexander said the South Pool's 500 acre feet of surface area would be only 100 acre feet in the North Pool.  I find it hard to believe water could leave a bowl, be placed in a cake pan and have less surface area.

The South Pool has something the North Pool doesn't, a regularly running river.  The move is intended to divert this flow away from agricultural uses, as described by the Bureau of Reclamation.

Much of the stored water is used to irrigate 10,000 acres of crop and rangeland (Reclamation 1994).
Brutal heat and no rain have the city doing all it can to utilize water resources.  Consider how bad the year has been relative to average:

Highest temperatures occur in July with an average high of 92.7⁰. The area averages 271 days of sunshine and 21.2 inches of rain per year. Recent rainfall totals are significantly less, as Tom Green County is currently experiencing a long period of drought (City of San Angelo 2009).
Paul Alexander showed his ignorance of Twin Buttes when he suggested putting a boat ramp on the south side of the North Pool.  The area's low grade made it unsuitable for a ramp.  He's likely more on target, but there are holes in his analysis. 

If the city does something, I hope they find out what actually happened.  That seems a rarity for this group of leaders.