AIS Projects
Check out all of the AIS projects below!
Tahoe Keys Bubble Curtain
The Tahoe Keys Bubble curtain was installed in 2018 to create a barrier that prevents AIS fragments from entering Lake Tahoe. During 2020 the TKPOA AIS program installed a new 7.4 horsepower compressor that provides more air flow to the bubble curtain, creating a better barrier. This project was funded in part by the League to Save Lake Tahoe.
For more information on the Bubble Curtain click here
Back-Up Station
Instructs boats to back up to dislodge vegetation fragments from their props and rudders.
The TKPOA implemented the Boat Back-Up Station in 2016 and has continued to improve on the design. The system now utilizes the combined strategies of the Boat Back-Up station, bubble curtain, bottom barriers and seabins. The Boat Back-Up station notifies boaters to back up, ensuring that weeds caught on their props and rudders are dislodged before they enter the lake.
Bottom Barriers
Synthetic mats are installed to block out sunlight and smother aquatic invasive weeds on the floor of the lagoons. These barriers are installed at locations requested by homeowners who volunteer for this program. The Association is allowed a total of five acres of bottom barrier coverage.
Check out the 'Take Action' page to learn how to sign up for a Bottom Barrier!
Laminar Flow Aeration (LFA)
The TKPOA currently has 2 LFA sites, one adjacent to Christie Dr. North of Venice Dr and another in the West Channel entrance. LFA involves bubbling air through several small diffusers on the bottom of the lagoons. The air bubbles create circulation, increasing the amount of oxygen at the bottom of the lagoons, which promotes microbial activity in the sediment and “muck”. This change is intended to make the nutrients less available for the weeds and algae, which should reduce the rate and amount of weed growth in the area of the LFA test. Status: TKPOA has received financial support for this project from The League to Save Lake Tahoe.
This project was funded in part by the League to Save Lake Tahoe.
For more information on LFA click here
Hydroacoustic Scans
The AIS staff map plant density in the Tahoe Keys Lagoons. It is done using an HDS 7 Lowrance system with a HDI 83/200 Transducer mounted on the AIS boat and Biobase software that determines plant density based on the structure scan produced by the Lowrance system. These scans help the WQ department determine which areas have the worst infestation.
Circulation System
Circulation system moves water to disrupt algae proliferation. The Tahoe Keys was constructed with a water circulation system to keep water in the lagoons as clean as possible. This system used coagulation to reduce Total Dissolved Solids (TDS) and decrease turbidity helping keep the lagoons relatively clear.
Best Management Practices
The TKPOA is developing Best Management Practices (BMP) to prevent runoff from houses and yards that may contain nutrients that would fuel vegetation growth.
Stormwater and erosion control BMPs are retrofit measures required on all private properties in the Lake Tahoe Region to control erosion and infiltrate stormwater before it leaves the property. BMPs are proven to prevent sediment, nutrients, and other pollutants from entering waterways. BMPs include pollutant source control measures which reduce the amount of pollutants present and hydrologic source control measures to direct stormwater and snowmelt runoff so that pollutants are filtered out and prevented from entering surface water.
Harvesting Operations
Harvesting is the primary control method available to the Tahoe Keys today. Throughout the summer months the TKPOA operates harvesters that remove vegetation from designated sections. During the months of July and August, harvesters focus on navigation lanes so boaters can travel through the lagoons. During the last few weeks of the harvesting season harvesters focus on removing as much vegetation as possible by harvesting the entire section between homeowner docks. This helps to reduce available nutrients and may possibly help reduce vegetation growth the following season.
Lagoon Friendly Landscaping
TKPOA encourages phosphorus free fertilizers to decrease available nutrients for aquatic macrophytes.
The Lake and Lagoon Friendly Landscaping educational campaign was initiated in 2017 to annually inform property owners on best practices to reduce runoff and pollutants through better landscaping techniques.
Most landscaped areas in the Tahoe Keys Facility are under the control of individual homeowners who may maintain their properties or may contract private landscaping companies for maintenance. TRPA acknowledges and tracks BMP installation by inspecting and issuing a BMP Certification or Source Control Certificate (SCC) letter to the property owner. A BMP Certificate certifies that the BMPs are properly installed and functioning on a property.
For more, read: TKPOA Landscape Conservation Guidebook
Tahoe Keys Complex Restoration
The Tahoe Resource Conservation District (TRCD) has funded diver assisted hand pulling within the Tahoe Keys Complex along with the East and West Channels. This project was started in 2020 and will continue into 2021.
For more information on diver assisted hand pulling click here
UV Light
This method is currently being tested at the Lakeside Marina. Depending on the outcome of the UV light test, this method could also be one of TKPOA’s many tools in their integrative approach to managing the invasive plants.
Diver Assisted Suction Harvesting
Divers pull plants by hand and put them into a suction hose to be collected from staff on the surface. Diver assisted hand pulling was conducted throughout the Tahoe Keys Complex outside of the West Channel in 2020 and is planned for the East Channel in 2021.
For more information on diver assisted hand pulling click here
The Importance of AIS Program
Aquatic Invasive Plants are a Widespread Problem
Around the Country
USGS Map of Aquatic Invasive Plants, 2018
Aquatic invasive plants are a challenge for numerous bodies of water around the country, costing billions of dollars each year, according the the US Fish and Wildlife Service. Click here to see how other areas around the west are handling the challenge.
Around Lake Tahoe
Tahoe Keys Weeds
Aquatic invasive plants affect all marinas and numerous shallow, warm areas around Lake Tahoe and continue to spread, constituting the most immediate threat to Lake Tahoe, according to the University of Nevada, Reno's 2015 Implementation Plan for the Control of Aquatic Invasive Species within Lake Tahoe. Curlyleaf pondweed, able to grow in deeper, colder waters, has begun to spread more rapidly than Eurasian watermilfoil.
In the Tahoe Keys
Tahoe Keys Hydroacoustic scan 8/5/2020
More than 95 percent of the Tahoe Keys' 172-acre lagoons are infested with aquatic invasive plants. Tahoe Keys Property Owners Association has both aggressively managed these plants with available methods and proactively sought long-term solutions to bring the infestation under control once and for all.
