Gateway Natural Area put-in

The most convenient put-in for Filter Plant, Gateway Natural Area <https://www.fcgov.com/naturalareas/finder/gateway> is owned by the City of Fort Collins. It has a large parking lot, picnic areas, and a boat ramp. Entry costs $8/day, or an annual pass is $40/year. Gateway Natural Area seems to be the only place that the City charges for entry, but the annual pass is separate from County and State annual passes.