Debris loosed by hydraulic mining above Marysville raised the riverbeds of both the Feather and the Yuba Rivers and rendered the city vulnerable to flooding during winter storms and spring run-offs. The city built a levee system that is still maintained today. The levee system sealed the city off and has made additional city growth virtually impossible; as such the population has not increased much since their construction and Marysville is known as "California's Oldest 'Little' City." The hydraulic mining debris choked the Feather River and soon the riverboats could not make the trip to Marysville.
Debris loosed by hydraulic mining above Marysville raised the riverbeds of both the Feather and the Yuba Rivers and rendered the city vulnerable to flooding during winter storms and spring run-offs. The city built a levee system that is still maintained today. The levee system sealed the city off and has made additional city growth virtually impossible; as such the population has not increased much since their construction and Marysville is known as "California's Oldest 'Little' City." The hydraulic mining debris choked the Feather River and soon the riverboats could not make the trip to Marysville