Plan For The Tahoe Keys Lagoons Presentation to the TRPA Board of - - PowerPoint PPT Presentation

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Draft Integrated Weed Management Plan For The Tahoe Keys Lagoons Presentation to the TRPA Board of Directors September 23, 2015 Aquatic Weeds Removed from the Tahoe Keys 20,000 18,600 18,300 17,500 18,000 16,700 16,000 Volume in Cubic

SLIDE 1

Draft Integrated Weed Management Plan For The Tahoe Keys Lagoons

Presentation to the TRPA Board of Directors September 23, 2015

SLIDE 2

Aquatic Weeds Removed from the Tahoe Keys

100 350 550 650 1,800 1,425 4,400 13,400 16,700 18,30017,500 18,600 2,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 18,000 20,000

1984 1985 1986 1987 1988 1989 2007 2010 2011 2012 2013 2014 Volume in Cubic Yards Year

September 23, 2015 2

SLIDE 3

Tahoe Keys Property Owners Association September 23, 2015 3

Tahoe Keys Property Owners Association

Tahoe Keys Beach & Harbor Association Tahoe Keys Marina and Yacht Club Lagoon Associates, Inc. TKV Properties CA Tahoe Conservancy Tahoe Keys Homeowners

Tahoe Keys Landowners

SLIDE 4

IWMP Research & Development

2011 2012 2013 2014 2015 2016 2017 Previous Plans, Consultations, and Experiments Agency Scoping on Content/Process Draft IWMP Preparation Expert Panel Review/ Input

September 23, 2015 Tahoe Keys Property Owners Association 4

SLIDE 5

IWMP Next Steps

2011 2012 2013 2014 2015 2016 2017 Public Review of Draft IWMP Refine and Submit Proposed Plan to Agencies Formal Agency and Public Review/ Permitting

September 23, 2015 Tahoe Keys Property Owners Association 5

SLIDE 6

Tahoe Keys Property Owners Integrated Weed Management Plan Overview

Photo credit: Lake Tahoe Real Estate www.laketahoerealestateblog.com

Orientation to the Tahoe Keys Lagoons
Aquatic weed problem
Need for improved management approach
Goals and Objectives the plan
IWMP review process:

>Public and Agency Input >Expert Panel Input

Summary

SLIDE 7

Tahoe Keys- South Lake Tahoe

Photo credit: Lake Tahoe Real Estate www.laketahoerealestateblog.com

West Channel East Channel Lake Tallac Lake Tahoe Main Lagoon Marina Lagoon

SLIDE 8

Tahoe Keys- South Lake Tahoe

1,500 Homes, 950 docks, 1,400 boats
Commercial Marina and Boat Launch
Narrow surface connections to Lake

Tahoe

Eight land owners/managers
Shallow, warm water
Three aquatic weeds degrade beneficial uses of the

Keys Lagoons: > 90% of Lagoon waters are affected

September 23, 2015 Tahoe Keys Property Owners Association

SLIDE 9

Non-native and nuisance plants in the Tahoe Keys:

Eurasian watermilfoil (Myriophyllum spicatum)
Curlyleaf pondweed (Potamogeton crispus)
Native Coontail (Ceratophyllum demersum)
M. spicatum
P. crispus
P. crispus turions:

Produced in early summer; Sprout in fall

September 23, 2015 Tahoe Keys Property Owners Association 9

SLIDE 10

Tahoe Keys – Priority for Lake Tahoe

Lakewide AIS Implementation Plan
Aquatic invasive plants in Tahoe Keys
Warm-water fish using habitat created by invasive plants
Eurasian watermilfoil
First found in Tahoe Keys in 1980s
Now appears in many Lake Tahoe near-shore zones
Curlyleaf pondweed
First found in Tahoe Keys Channels in 2003
Now has established throughout Tahoe Keys Lagoons
IWMP Expert Review Panel concerns about increasing risks to Lake

Tahoe

Habitat not limited to near-shore zones

September 23, 2015

Tahoe Keys Property Owners Association 10

SLIDE 11

2014 TKPOA Survey (point sampling)

RED Areas = 100 % Eurasian watermilfoil

SLIDE 12

Current Management Relies on Aquatic Weed Harvesters

5 Harvesters
4 Work

Boats

12 Seasonal

Employees

Training
Insurance
Administrati
n
>$400k/Yr
Not

Controlling Weeds Well

Contribute

plant fragments

September 23, 2015 Tahoe Keys Property Owners Association 12

SLIDE 13

IWMP Goal

To help protect the ecology, to enhance the recreational and aesthetic qualities, and to maintain the commercial uses of Lake Tahoe by controlling nuisance aquatic plants in the Tahoe Keys lagoons.

September 23, 2015 Tahoe Keys Property Owners Association 13

SLIDE 14

IWMP Objectives

Minimize spread of weeds to Lake Tahoe
Enhance habitat for native plants and animals
Restore recreational and commercial uses in the Keys
Establish adaptive management using best available

technologies, BMPs and quantifiable results

Contribute to Tahoe Region reduction in greenhouse

gases by minimize impacts of management on air quality.

September 23, 2015 Tahoe Keys Property Owners Association 14

SLIDE 15

Examples of Control Methods Under Consideration

Modified harvesting and monitoring techniques Bottom barrier placement (limited to 5 acres per year) Diver assisted weed removal Prevention and Boat maintenance practices

September 23, 2015 Tahoe Keys Property Owners Association 15

SLIDE 16

NOTE: Methods are to be integrated and tailored for use in specific sites

Mechanical and Physical:

> Improved fragment capture and removal from Harvesting >Strategic use of bottom barriers and diver hand/suction removal

Cultural:

>Storm water management/ reduction in nutrient inputs >Property owner yard, shoreline, and dock maintenance practices >Boat maintenance practices (Reduce transport of plants) >Prevention of new introductions

Chemical

>EPA-approved herbicide applications in selected sites (currently not permitted in Lake Tahoe)

Proposed Control Methods for the IWMP

September 23, 2015 Tahoe Keys Property Owners Association 16

SLIDE 17

SLIDE 18

Summary

 The IWMP will reduce deleterious impacts of aquatic weeds.  Public, private and agency stakeholders have participated- and will continue to provide input and extensive review.  The IWMP is adaptive and relies on intensive monitoring for annual strategic actions.  The IWMP incorporates proven, widely used technologies that are tailored to specific Keys Lagoon sites.

September 23, 2015 Tahoe Keys Property Owners Association 18