Chittenden-Ballard Locks Fish Ladder

The salmon ladder constructed by the Chittenden-Ballard Locks helps protect the lives of salmon and ensure that they can travel at least 40 miles upstream to reproduce and continue life. The ladder was renovated in 1976 to improve the conditions for conserving the salmon populations. Today, it has been reported that the ladder has 21 steps that help the salmon travel upstream. The ladder protects species such as the Coho, Chinook, and Sockeye from factors such as overfishing. When these salmon travel through the fish ladder, they are often in what is called an 'ocean phase' and can be recognized through little spots along their back. Many salmon generally reach the spawning areas by early fall.

This map shows the Salmon's path during spawning season, from the Issaquah Salmon hatchery, through Lake Sammamish and the Sammamish River, through Lake Washington to Lake Union. Finally, the last step is climbing through the Ballard Locks to the Puget Sound.

Sockeye Salmon Population In Lake Washington

Sockeye Salmon are the type of salmon with the largest population within Lake Washington. Groups of Sockeye that hatch in Lake Washington return home every four years. One of the more recent groups was the 2017 population that did not return till 2021. There are sometimes exceptions with male Sockeye Salmon known as "jacks" that return early and help diversify the overall population. While other types of salmon, such as the Coho, have populations of 20,000, the Sockeye Salmon population can be as high as over 500,000. 

Even though there have been government efforts to save the lives of salmon, due to factors such as pollution, the Sockeye Salmon population has decreased. According to data, 133,019 Sockeye Salmon arrived through the locks in 2017, but only 38,618 in 2021. Chinook Salmon populations have also not been close to their highest record of 31,631 since 2009. While not every year is expected to have lots of salmon returning, the data shows concerning results. However, exceptions include the Coho population, which increased from 7,895 in 2020 to 30,679 in 2021.