Existing law establishes the Santa Monica Mountains Conservancy and prescribes the membership, functions, and duties of the conservancy regarding the acquisition, preservation, and improvement of real property within the Santa Monica Mountains Zone, as defined. Existing law establishes within the conservancy the Upper Los Angeles River and Tributaries Working Group with designated membership of no more than 23 appointed representatives. Existing law requires the working group to develop, through watershed-based planning methods and community engagement, a revitalization plan for the Upper Los Angeles River, the tributaries of the Pacoima Wash, Tujunga Wash, and Verdugo Wash, the Arroyo Seco, and any additional tributary waterway that the working group determines to be necessary. Existing law requires the working group to submit the revitalization plan to the conservancy for adoption, and requires the conservancy to submit a copy of the revitalization plan to the Assembly Committee on Water, Parks, and Wildlife and the Senate Committee on Natural Resources and Water, as specified. This bill would add an additional member to the working group, for a total of no more than 25 appointed representatives. The bill would require one of the representatives appointed to the working group to represent the city council district within the City of Los Angeles with the greatest number of Upper Los Angeles River miles. The bill would require the working group to meet at least once each year to evaluate and report on implementation of the revitalization plan to the conservancy, and propose amendments to the revitalization plan to the conservancy for adoption. The bill would require the working group to submit proposed amendments to the revitalization plan to the conservancy, and would require that the conservancy take action to adopt the proposed amendments, as specified.