Memorandum CITY OF DALLAS. August 9, 2012

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1 Memorandum CITY OF DALLAS August 9, 2012 TO Honorable Members of the Transportation & Environment Committee: Linda Koop (Chair), Sheffie Kadane (Vice Chair), Delia Jasso, Pauline Medrano, Vonciel Jones Hill, Sandy Greyson sufllecr Dallas Water Utilities Update on Zebra Mussels Briefing On Tuesday, August 14, 2012, you will be briefed on the Dallas Water Utilities Update on Zebra Mussels at the Transportation and Environment Committee meeting. The briefing material is attached for your review. Please contact me if you need additional information. Forest E. Turner Assistant City Manager Attachment cc: Honorable Mayor and Members of the City Council Mary K. Suhm, City Manager Rosa A. Rios, City Secretary Thomas P. Perkins, Jr., City Attorney Craig D. Kinton, City Auditor C. Victor Lander, Administrative Judge A.C. Gonzalez, First Assistant City Manager Ryan S. Evans, Assistant City Manager Jill A. Jordan. P.E., Assistant City Manager Joey Zapata, Assistant City Manager Jeanne Chipperfield, Chief Financial Officer Edward Scott. City Controller Stephanie Cooper, Assistant to the City Manager Dallas Together, we do it better!

2 Dallas Water Utilities August 14,

3 Purpose With the recent discovery of zebra mussels in Lake Ray Roberts, the purpose of this briefing is to provide background information on zebra mussels, Dallas current zebra mussel related activities, and the potential impacts to Dallas water supply system 2

Outline Background Dallas Current Activities Potential Impacts Next Steps Appendix Zebra Mussel Facts Zebra Mussel Impacts USGS Zebra Mussel Monitoring North Texas Guidance Manual

4 Outline Background Dallas Current Activities Potential Impacts Next Steps Appendix Zebra Mussel Facts Zebra Mussel Impacts USGS Zebra Mussel Monitoring North Texas Guidance Manual TRWD/Dallas Integrated Pipeline design TPWD Media Campaign Zebra and Freshwater Mussel Comparison Zebra mussels found on a U.S. Geological Survey passive sampler in Lake Ray Roberts, July 23,

5 What are Zebra Mussels Zebra Mussels are: Invasive species Aquatic nuisance Ecological misfortune Attach to any hard surfaces (i.e., rocks, intakes, pipes, hard shelled aquatic species, etc.) Not a water quality hazard 4

6 Significant Impacts of Zebra Mussels Ecological Disrupts the food chain Clarifies the water column allowing light to penetrate deeper Increases water temperature Increases vegetative growth Concentrates blue-green algae Blooms can be toxic to other aquatic life Attachment to other species inhibiting: mobility reproductively feeding breathing Decreases dissolved oxygen in the water Recreational Decreases in food sources decrease sport fishing populations Increased vegetation can hinder boating and swimming Fouls boats hulls Clog engine intakes Sharp edged shells accumulate along shores 5

7 Zebra Mussels are a Nuisance Not a water quality hazard Attach to Water Intake Facilities Intake screens Pumps Monitoring equipment Pipes Etc. Will require additional cleaning to remove 6

8 Zebra Mussels in Texas 7

9 Lake Texoma Zebra Mussel Infestation Lake Texoma 72-in pipeline Lake Texoma Pump Station Intake Screen Lake Texoma shore August

10 North Texas Municipal Water District Current and Future Actions In April 2009, Zebra Mussels were discovered in Lake Texoma. North Texas Municipal Water District stopped pumping when zebra mussels were found (federal law prohibits the transfer of invasive species across state lines). Implementing the North Texas Zebra Mussel Barrier Plan (i.e. the construction of a 46-mile pipeline extension to deliver Texoma water directly to the NTMWD water treatment plant) Approximately $300 million in cost. Participating in the development of the North Texas Zebra Mussel Guidance Manual. Representative Ralph Hall introduced H.R. 6007: North Texas Zebra Mussel Barrier Act of 2012 o Bill exempts NTMWD and Greater Texoma Utility Authority from the Lacy Act amendments of 1981 by using a closed conveyance system from Texoma to its treatment facilities. o Introduced and referred to the House Natural Resources Committee on June 21, o The subcommittee on Fisheries, Wildlife, Oceans, and Insular Affairs held a hearing on July 19, o Passed out of House Natural Resources Committee, August 1,

11 Dallas Current Efforts In 2010, Zebra Mussel Monitoring added to City s USGS Cooperative Agreement In August 2011, the City Council approved participation in the development of the U.S. Army Corps of Engineers North Texas Zebra Mussel Guidance Manual. In June 2011, the City Council approved participation in the TPWD Zebra Mussel Public Education Campaign Clean, Drain, Dry Your Boat brochures distributed around Lake Ray Hubbard and posters displayed at marinas. In March 2012, Tarrant Regional Water District began Control of Invasive Species Study for the TRWD/Dallas Integrated Pipeline Design. 10

12 Zebra Mussel Found in Lake Ray Hubbard Lake Lavon Lake Ray Hubbard May 2011, U.S. Geological Survey found one live Zebra Mussel on the boat ramp at Chandlers Landing. 11

Zebra Mussels Found in Lake Ray Roberts Lake Ray Roberts On July 17, 2012, Texas Parks and Wildlife found Zebra Mussels at the following locations: Sanger Marina West Side of Dam Jordan

13 Zebra Mussels Found in Lake Ray Roberts Lake Ray Roberts On July 17, 2012, Texas Parks and Wildlife found Zebra Mussels at the following locations: Sanger Marina West Side of Dam Jordan Park Stilling Basin On July 23, 2012, U.S. Geological Survey found Zebra Mussels at the following locations: Sanger Park/Marina Boat Ramp Jordan Park Boat Ramp Isle du Bois Boat Ramp 12

14 USGS Zebra Mussel Monitoring Sites 13

15 Potential Control Strategies CHEMICAL NON-CHEMICAL Oxidants: Chlorine Bromine Ozone Chloramines Chlorine dioxide Potassium permanganate Hydrogen peroxide Physical: Velocity Removal Pipeline pigging Manual cleaning/scraping Coatings/materials Filtration/screening Nonoxidizing Molluscicides: Organic molluscicides Potassium salts Copper-ion generation ph depression Oxygen scavengers Biological: Desiccation Thermal Bacterial Design/Operation: Redundant piping Facility shutdown EXPERIMENTAL Ultraviolet radiation Acoustics Source: Draft North Texas Zebra Mussel Guidance Manual Electric fields Air bubbling Most common control measure worldwide is physical removal 14

16 Potential Impacts to Dallas There is no immediate impact to the City of Dallas. Once zebra mussels migrate down the Elm Fork the following are vulnerable to infestation: o Dallas water treatment plant intakes and raw water lines. o Intakes and piping of Dallas Untreated Water Contract customers in Lewisville and the Elm Fork. o Water quality monitoring and flow gage installations o Stormwater facilities. Not a water quality hazard Specific cost estimates are not known at this time: o Current literature review contains wide range of cost depending on type, size and use of facilities. o North Texas Zebra Mussel Guidance Manual will assist in predicting the potential cost. 15

17 Next Steps Continue Zebra Mussel Monitoring through U.S. Geological Survey Increase monitoring frequency in Elm Fork System (Lakes Ray Roberts, Lewisville and Grapevine). Add monitoring sites along the Elm Fork of the Trinity upstream of Dallas intake structures. Finalize North Texas Zebra Mussel Guidance Manual: Continue to stay abreast of ongoing invasive species research and protection and control methods. Continue to incorporate invasive species protection and control in capital improvement projects. 16

Appendix Zebra Mussel Facts Zebra Mussel Impacts USGS Zebra Mussel Monitoring North Texas Guidance Manual TRWD/Dallas Integrated Pipeline design TPWD

18 Appendix Zebra Mussel Facts Zebra Mussel Impacts USGS Zebra Mussel Monitoring North Texas Guidance Manual TRWD/Dallas Integrated Pipeline design TPWD Media Campaign Zebra and Freshwater Mussel Comparison Zebra Mussels found by Texas Parks and Wildlife Department at Lake Ray Roberts July 17,

Zebra Mussel Facts Scientific Name: Dreissena polymorpha Size: Maximum length 2 inches Life span: 4 to 5 years Habitat: fresh water at a depth of 6 to 24 feet Reproduction: Female can produce up to 1

19 Zebra Mussel Facts Scientific Name: Dreissena polymorpha Size: Maximum length 2 inches Life span: 4 to 5 years Habitat: fresh water at a depth of 6 to 24 feet Reproduction: Female can produce up to 1 million eggs per year Approximately 2% reach adulthood Life Cycle: Veliger (larval stage) Juvenile (settle and attach) Adult (reproductive stage) Feeding/Food Filter feeders (an adult can filter up to 1 quart of water a day) Planktonic algae and zooplankton Zebra Mussel Life Cycle Source: 18

20 Where Did They Come From? Native to the Baltic Sea area in Eastern Europe. Introduced in Lake Saint Clair (Great Lakes) in the mid 1980 s. Since introduction in Great Lakes they have spread to the Gulf Coast. Zebra mussels can be spread overland via boats (hulls, trailers, bilge and ballast water, live wells and cooling systems) as well as migratory birds. 19

21 Zebra Mussel Impacts Zebra mussels attach to hard surfaces. Hard surfaces include native mussel shells, turtles, craw fish benthic macro invertebrates. When attached to other species, the other species loses its ability to move, feed, breath, and breed. One adult zebra mussel can filter up to one liter of water per day. The filter feed activity reduces the abundance of plankton (the food for small fish and other organisms). Declines in small fish mean a shortage of food for sport fish such as bass. Zebra Mussels do not eat blue-green algae. Blue-green algae can become dominate species. Blue-green algae blooms can be toxic. Because of the filtering, lakes have become clearer. With clearer water, sunlight penetrates deeper, causing more vegetative growth. Vegetation can become so thick that it can hinder swimming and boating. Zebra mussels are bioaccumulators. Any contaminant in the water can concentrate in zebra mussels. When eaten, the contaminant concentration increases through the food chain. As they become more prevalent, more animals will eat them increasing the chance that higher levels of toxins will be accumulated throughout the food chain. The zebra mussel s need to attach to hard surfaces is also economically detrimental. Fishing and recreational - zebra mussels foul boat hulls and plug water systems used in motors, air conditioners and heads Water Supply - once inside a pipe the zebra mussels layer on top of each other eventually causing reductions in pumping capabilities and even complete blockages (municipal, industrial, commercial and domestic). Increase the deterioration of piers. Increase the corrosion of steel and concrete Sink navigational buoys because of the additional weight. Beaches can become covered in the sharp zebra mussel shells and the odor given off by decaying mussels can be unpleasant, both of which result in reduced recreation. 20

U.S. Geological Survey USGS began sampling: o Lake Ray Hubbard in October 2010 o Lake Lewisville in June 2011 o Grapevine and Ray Roberts in October 2011 o

no positive samples since initial discovery o Lake Ray Roberts on July 17, 2012, confirmed July 23, 2012 o Published Fact Sheet USGS Zebra Mussel Monitoring

22 U.S. Geological Survey USGS began sampling: o Lake Ray Hubbard in October 2010 o Lake Lewisville in June 2011 o Grapevine and Ray Roberts in October 2011 o Lake Fork Reservoir and Lake Tawakoni in November 2011 o Lake Palestine in April 2012 Zebra Mussel(s) found: o Lake Ray Hubbard in 2010 (one found and removed) no positive samples since initial discovery o Lake Ray Roberts on July 17, 2012, confirmed July 23, 2012 o Published Fact Sheet USGS Zebra Mussel Monitoring Program for North Texas Plankton tow net at Lake Ray Roberts (July 23, 2012) Passive sampler at Lake Ray Roberts (July 23, 2012) 21

23 North Texas Zebra Mussel Guidance Manual Study began in August The Study will identify the following zebra mussel: Detection and monitoring techniques Facilities at risk Infestation consequences environmental damages and costs Containment and control techniques Operational mitigation strategies Probable costs of selected strategies Public outreach and education needs and approaches Regional management and collaboration Compile legislation, regulations, and rules Guidance Manual is scheduled to be finalized by the U.S. Army Corps of Engineers by December

TRWD/Dallas Integrated Pipeline Design To develop control strategies including physical and/or chemical approaches to limit the spread, growth and attachment of zebra mussels and other aquatic

24 TRWD/Dallas Integrated Pipeline Design To develop control strategies including physical and/or chemical approaches to limit the spread, growth and attachment of zebra mussels and other aquatic invasive species. Evaluate and incorporate components in the pump station and pipeline design and original construction in the event of a zebra mussels or other aquatic invasive species infestation. To effectively control the impact to the operation and maintenance of the system. Tarrant Regional Water District Cedar Creek Reservoir Intake 23

TPWD Media Campaign TPWD began broadcast, print and electronic media campaign concentrated around the Lake Texoma area of North Texas in August

25 TPWD Media Campaign TPWD began broadcast, print and electronic media campaign concentrated around the Lake Texoma area of North Texas in August TPWD campaign refers people to the Texas Invasives website for additional information for additional information. 24

26 TPWD Media Campaign Website 25

species can be found in Texas Habitat attach to the surface of any hard surface partially bury in mud, sand, gravel and cobble Reproduction females release eggs into the water males release sperm

27 Zebra Mussel vs. Freshwater Mussel Zebra Mussel Freshwater Mussel Species Dreissena polymorpha Approximately 300 species in North America 70% are considered endangered, threatened or of special concern more than 50 species can be found in Texas Habitat attach to the surface of any hard surface partially bury in mud, sand, gravel and cobble Reproduction females release eggs into the water males release sperm into the water fertilization occurs in the water Veligers (larval stage) are free swimmers male release sperm into the water female inhale sperm during normal feeding and respiration fertilization occurs in the female Glochidia (larval stage) develop in the female and are released Glochidia when released live as a parasite on a fish Life span 4 5 years thin shelled 4-10 years thick shelled years Zebra Mussels attached to a freshwater mussel 26

Zebra & Quagga Mussel Invasion in North America

Zebra & Quagga Mussel Invasion in North America David K. Britton, Ph.D. U.S. Fish & Wildlife Service Two Invading Species Zebra Mussels Driessena polymorpha Quagga Mussels Driessena rostriformis bugensis