Public drainage easements shall include all drainage at least to the limits of the 25-year flood as indicated on the floodplain maps or as determined on the basis of the Drainage Criteria Manual, as amended. All drainage easements across private property shall contain the necessary language to permit the required unobstructed water flow, require maintenance of vegetation by the property owner(s), and permit the necessary access by city officials for inspection and repairs. The minimum drainage easement width shall be 25 feet. All easements, 25 and 100-year floodplain boundaries and water quality zones shall be clearly shown on drainage plans and the site plan.