Rickreall Watershed and Invasive Species
No Boats on Aaron Mercer Reservoir
Boats and other watercraft in Aaron Mercer Reservoir create significant risks to the City’s drinking water. These risks are primarily from invasive species transfer into the reservoir from other lakes and reservoirs. As such, Dallas City Code Section 5.430 prohibits the use of boats and other watercraft in Aaron Mercer Reservoir.
The invasive species include Cyanobacteria, Chinese and Japanese Mystery Snails, New Zealand Mudsnails, Zebra Mussels and Quagga Mussels.
Cyanobacteria are known as blue-green algae because they are aquatic and use sunlight to create food and support life. However they are not algae. They usually are too small to be seen, but sometimes can form visible colonies (called algai blooms) in slow moving water that are rich in nutrients. These blooms can occur at any time, most often in late summer or early fall. Cyanobacteria can be transferred into Aaron Mercer Reservoir from the hulls of boats that have been in infected areas. This type of bacteria is toxic and has been linked to human and animal illness around the world. The toxins produced from cyanobacteria blooms are some of the most powerful known to man. The introduction of cyanobacteria into Aaron Mercer Reservoir would, at the very least, complicate our treatment process and increase our costs.
Invasive mussels and snails of all types can also easily be transferred into Aaron Mercer Reservoir from the hulls of boats that have been in infected areas. They can host parasites and diseases that are known to infect humans. Their shells can obstruct intake pipe screens, interfere with the valve that controls flow from the reservoir and restrict water flow within the treatment plant. These organisms would, at the very least, increase needed maintenance, and costs throughout the system.
Information and resources for invasive plant species:
GardenSmart Oregon: A Guide to Non-invasive Plants
Oregon Ivasive Species Online Hotline
Managing Himalayan Blackberry in Western Oregon Riparian Areas (polkswcd.com)
For more information about invasive species in Oregon, please contact Oregon Department of Fish and Wildlife at 503.947.6000.
Rickreall Watershed Management Assessment
The Polk Soil and Water Conservation District conducted a natural resources inventory in 2011 and 2012 for the City of Dallas to determine the best management strategies to protect the city's sole source of drinking water, the Rickreall Creek Watershed. The 2013 report is called the Rickreall Watershed Management Assessment.
