City of Portland, OregonDefines the boundary of the Columbia South Shore Protection Zone -- Additional Information: Category: Boundary Purpose: To allow Bureau staff to design, construct, utilize, analyze and manage the Bureau's water supply and distribution system. Update Frequency: As needed -- Metadata Link: https://www.portlandmaps.com/metadata/index.cfm?&action=DisplayLayer&LayerID=53757ArcGIS DynamicMapLayerhttps://hub.arcgis.com/datasets/f17ce1671b3a4a449db3f9eee0bc7147_29engPortlandMaps Open DataPublicColumbia South Shore Wellhead Protection Area [Oregon--Portland]Web servicesOregon--PortlandOregonLast Modified: 2025-11-24