The New Lake Effect

Hook Spit – 2014 Houston Boat Show
January 20, 2014
Sea Changes
March 25, 2014


Matt Williams

Scroll through the long list of reservoirs under constant watch by the Texas Water Development Board and it is pretty obvious that most Texas reservoirs continue to starve for water as the result of a wretched drought cycle that has been hanging on for years.

Low water is inevitable when more water goes out of a lake than goes in over a long period of time. The impacts are especially noticeable during crippling drought years like 2011. Just about every reservoir in the state dipped to a record low as a direct result of that epic dry spell. In fact, a couple of West Texas impoundments dried up completely.

Although some parts of Texas have received welcomed rainfall over the last 12-18 months that has curtailed dry conditions and boosted water levels on some lakes, most of the state as of December 2013 remained in some stage of drought, according the U.S. Drought Monitor. Likewise, water levels on dozens of reservoirs remain well below the full pool mark. Some are so low that it may take a 100-year flood fill them up.

To wit:

In Central Texas, Lake Travis was 52.92 feet low; Buchanan, 31.60. Down south, Falcon and Choke Canyon were at minus 26.78 and 22.78 feet, respectively. Panhandle reservoirs like O.H. Ivie (-43.70) and O.C. Fisher (-51.76) have been extremely hard hit, but conditions are even worse at Meredith, which was pushing the -90-foot mark just before Christmas. Several North Texas lakes including Lavon (-12.76), Ray Hubbard (-6.87), Lewisville (-8.25) and Ray Roberts (-7.54) are still feeling the pinch, as well.

To find any normalcy in Texas lake levels these days you pretty much have to look to deep East Texas, where drought conditions have lifted and many reservoirs are closer to full pool than they have been in several years. As a result, some of these reservoirs are likely undergoing a biological phenomenon that fisheries scientists sometimes refer to “trophic upsurge.”

Better known as the “new lake effect,” trophic upsurge is what happens when a reservoir refills or records a significant rise in water level following a lengthy period of low water. Here’s how it all goes down:

The Highs of Low Water

When water levels fall below normal and stay there for an extended period, hundreds and sometimes thousands of acres of the lake bed normally covered by water are suddenly exposed to direct sunlight. This causes grasses, weeds, bushes, trees and other Lake Fork Dock Beforeforms of terrestrial vegetation native to the landscape to sprout on shorelines, vast flats, tapering points and other areas that may not have seen daylight in years. The longer the lake remains low, the thicker and more widespread the new growth vegetation becomes.

When water levels rise, all the junk that grew during the low period is inundated. This displaces a sudden influx of nutrients into the water and creates a jungle of underwater cover for young fish to hide in, thus leading to increased survival and recruitment while at same time creating an abundance of fresh targets for fishermen to toss their lures around.

Another benefit occurs as the newly-flooded weed beds begin to die and decompose. This results in another big shot of nutrients into the water, which in turn benefits plankton and other microscopic plants and animals that are the foundation of the food chain. The nutrients also act as a liquid fertilizer for the lake’s bottom, causing dormant native and non-native vegetation seed banks to spring back to life with new growth hydrilla beds, lily pads and other aquatic plants. This creates even more quality habitat where sport and forage fish populations can thrive.Lake Fork Dock-After

The Proof’s In the Puddin’

The new lake effect bolsters all sorts of aquatic life, but it can be particularly beneficial to largemouth bass populations. Many of the state’s top bass fisheries have rich histories of ebb and flow water cycles, but some are naturally more extreme than others.

A good example is Lake Falcon in deep South Texas. The Texas/Mexico border lake has a long history of fluctuating as much as 20-30 feet, mainly because of heavy irrigation demands downstream.

The down cycle was especially severe throughout much of the 1990s and early 2000s, when the lake fell to more than 50 feet below conservation level. The decade-long drought finally ended between 2002-04, when 10 years’ worth of new growth terrestrial vegetation was gradually inundated by water.

Falcon’s bass population responded with a vengeance. Likewise, the lake fished off the charts for several years as reflected by a long list of tournament results that read like something out of a fairy tale book.  Perhaps the most noteworthy event in Falcon’s history was the Bassmaster Elite Series event held there in April 2008. Pros and co-anglers milked the lake for more than 10,500 pounds of bass in four days. At the top of the pack was Mississippi pro Paul Elias, who weighed-in 20 bass weighing 132 pounds, 8 ounces — an average of nearly 6 1/2 pounds apiece.

The mark set a new four-day weight record for all competitive bass fishing events. Amazingly, Elias was joined in the Top 12 by 11 other anglers who cracked the fabled century mark, including Alabama’s Terry Scroggins, who weighed in a whopper limit weighing 44-pounds, 4-ounces during the final round.

Bass fisheries at lakes Amistad and Choke Canyon have had similar bust and boom cycles over the years. So have those at Sam Rayburn, Toledo Bend and a passel of smaller lakes like Nacogdoches, Pinkston and Lake O’ The Pines, just to name a few.Low Water

The point to be made by all of this is low water is not necessarily a bad thing. True, getting around in a boat or even launching one when the bottom falls out of a lake can be a hassle at times.

Low water also can deter weekend and holiday traffic to the point of creating financial strains on mom and pop tackle shops, gas stations, restaurants, hotels and fishing guides.

But there is a silver lining to it all. Big rains will eventually come and lakes will refill. In many instances the process will transform a tired honey hole into a vibrant reservoir that fishes like a brand new one again.

Comments are closed.