The city and county of Denver is empowered to extend and improve said channel beyond and outside the limits of the city and county of Denver when in the opinion of the council of said city and county the extension and improvement of said channel beyond the boundary line of said city and county shall more effectually and advantageously accomplish the purpose and object of sections 30-11-204 to 30-11-207, and cause said improvement to be more beneficial to the inhabitants of the city and county of Denver and promote and protect the general health and general welfare.
C.R.S. § 30-11-206