Lake Aeration POLLUTANTS ADDRESSED: Phosphorus and Algal Blooms
POTENTIAL TREATMENT AREAS: Lakes in agricultural/ranch lands Lakes in development lands
DESCRIPTION: Various systems are available to aerate lake either by injecting air, mechanically mixing or agitating the water, or even injecting pure oxgen.
ALTERNATIVE MANAGEMENT MEASURES: Pole/Post Planting Vertical Bundle Willow Fascines Brush or Tree Revetment
LOAD REDUCTION MECHANISM: Increase the dissolved oxygen content of the water and, in some case, nuisance algal blooms can be reduced or a shift to a less objectionable algae species can occur. LAND USE CLASSIFICATION: Agricultural and Ranch Lands Disturbed Areas Urban Lands
PERMITTING REQUIREMENTS: Requirements vary by location. A permit under sections 404 and 401 of the Clean Water Act and from AZDPS before the use of herbicides is used in a waterbody.
ADDITIONAL BENEFITS: Increase fish and other aquatic animal habitat; improve the quality of domestic and industrial water supplies while decreasing treatment cost.
Arid Southwest
Contact county regional flood control district.
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Lake Aeration POLLUTANTS ADDRESSED: Phosphorus and Algal Blooms Level 300: ACTIVE MANAGEMENT
The Air-lift method exposes the water to the atmosphere where it obtains more oxygen.
LOAD REDUCTION POTENTIAL: LOW
MEDIUM
HIGH
ESTIMATED TIME FOR LOAD REDUCTION: IMMEDIATE
MONTHS2 YEARS
> 2 YEARS
EXPECTED MAINTENANCE: LOW
MEDIUM
HIGH
ESTIMATED COST: LOW
MEDIUM
HIGH
PLANNING AND IMPLEMENTATION: Photo courtesy of: Aquatic Plant Management Manual Methods http://www.ecy.wa.gov/programs/wq/plants/man agement/aqua022.html.
1. To properly choice and design an artificial circulation system, it will depend on the lake management goals and the physical characteristics of the lake; example, if the system is under sized the mixing will be incomplete. If the lake is large, it may require several systems.
. Riparian Planting Zone: Base flow/Toe Zone
2. Avoid placing the air diffusers too near the bottom of the lake, this will help to stop stirring up the sediment and resuspending it in the lake. Also, avoid placing the air diffusers to far above the lake bottom; this will stop the creation of an anaerobic zone (without oxygen).
Arid Southwest
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