Ultrasound Technology Restores Balance in A Recreational Lake in Texas

Chemical-free approach controls cyanobacteria, improves water clarity, and supports fisheries in phosphorus-rich lake.

Background

Lake Tanglewood is a 255-acre reservoir located in the Texas Panhandle, surrounded by a private residential community of about 500 people. This recreational lake constantly receives highly treated wastewater from the city of Amarillo, located in the Texas Panhandle region. During summer, the excess nutrients, especially phosphorus promote the growth of blue-green algae. As the algae photosynthesize, they increase the water’s pH levels.

The community had previously explored various lake treatment methods including chemical precipitation and nutrient mitigation, but legacy phosphorus in the sediment, persistent nitrate levels, and weak vertical mixing caused by seasonal stratification hindered sustained treatment impact. Additionally, the recreational lake lacked full flushing capacity, creating thermal stratification and internal nutrient recycling that further increased bloom conditions.

The Problem

Public Health & Safety Risks
Harmful algal blooms dominated the lake, producing toxins like microcystins, cylindrospermopsin, and saxitoxins—posing serious health risks to humans and pets. Residents reported sinus, skin, and throat irritation after water contact.

Recreational & Visual Impact
Thick surface scum, often described as “pea soup,” severely affected the lake’s appearance and limited recreational activities such as swimming, water skiing, and boating.

Ecological Strain
Excessive nutrient input from runoff (especially phosphorus and ammonia) disrupted the natural balance of the lake, fuelling algal blooms, reducing oxygen levels, and stressing aquatic life.

Measurable Results

To proactively address the HAB crisis, the Lake Tanglewood community unanimously voted to install 13 LG Sonic ultrasound systems in mid-2023. The systems were strategically deployed throughout the recreational lake, including key inflow zones and popular recreational areas.

Water clarity using secchi depth: Secchi depth is a standard method for assessing water clarity. It involves lowering a black-and-white Secchi disk into the water until it is no longer visible. The depth at which the disk disappears indicates the transparency of the water—the greater the depth, the clearer the water.

• Fishermen reported visibility of crankbaits (lures that are shaped like small prey, used to attract larger fish) at 5-6 feet depth post-installation. Before the system was installed, crankbaits weren’t visible beyond 12 inches.
• Swimmers and skiers could see clearly underwater indicating a significant reduction in turbidity.

Discussion

In dynamic water systems, where turbidity naturally fluctuates due to weather, inflows, and biological processes, maintaining clarity is a constant challenge. Yet, across 2023, the average turbidity levels across all stations remained consistently low often below 13.9 NTU even through periods typically prone to spikes. The lake’s pH levels dropped by approximately 10% (reading taken around July 2023, the warmest time of the year.)

This trend reflects more than just numbers; it suggests a system that adapts silently and effectively, helping preserve clarity without disrupting natural rhythms. Where occasional peaks did occur, they were brief followed by a swift return to stability.

In a world where water is always moving, this kind of sustained clarity doesn’t happen by accident. It’s a quiet affirmation that the right treatment, applied consistently, can hold the line even when conditions are anything but steady.

1- Fisheries & Health Recovery
Improved water quality and lower pH levels supported natural fish recruitment and strengthened overall ecosystem resilience. Baby catfish were observed for the first time in years, likely due to reduced environmental stress. Stocked Largemouth Bass showed higher survival rates, while Hybrid Stripers (Wipers) adapted well and helped manage shad populations. Florida Strain Bass dispersed more evenly across the lake. A revised stocking method, placing fish in sheltered coves using buckets which increased survival by offering immediate refuge and reducing stress.

2- System Durability & Operation
The MPC-Buoy systems proved durable in harsh conditions, withstanding 3–4 ft waves with solar panel that stayed functional. Buoys remain in place year-round with batteries removed in winter. Even during a major nutrient influx, the system prevented a predicted algal crash and protected the lake’s ecological balance.

3- Environmental Resilience
Even during a significant nutrient influx, which usually causes a rapid increase in algae followed by a sudden crash, the system kept the lake stable. It prevented algal collapse, helping maintain a healthy balance in the ecosystem. This protected aquatic life and supported water quality throughout the event.

Conclusion

Lake Tanglewood’s story is a testament to how proactive community engagement and advanced water quality technology can transform a lake ecosystem under stress. Within just one season of operation, LG Sonic’s ultrasound-based control system improved visual clarity, reduced cyanobacteria, supported natural fisheries, and created a safer, more enjoyable recreational environment.

As Dr. William Rogers concluded:

“Without LG Sonic, we would have had a major die-off. The system helped the lake buffer naturally and recover faster.”

(Die-off here refers to a large number of fish and other aquatic life dying suddenly due to low oxygen levels, high toxin concentrations from algal blooms.)