The council released its proposed plan change 6A (water quality) last year, heard submissions last September and notified the plan publicly in April.
The appeal period ended on Tuesday and the Environment Court confirmed 21 appeals had been lodged.
Those appealing included three district councils, environmental groups, farmers, irrigation companies, landcare groups and industry group representatives.
Submitters can still join appeals as interested parties up until June 25.
Council policy and resource director Fraser McRae said the appeals he had seen did not attack the underlying premise of the proposed water plan.
The plan aimed to maintain and improve the quality of water in Otago by implementing standards for rural run-off.
Instead. the appeals were concerned with clarifying the plan's wording and the discharge values, he said.
He hoped informal mediation with the appellants could start soon to see if their concerns could be worked out to the satisfaction of both parties.
If they could not, the matter would go to formal mediation and if that was unsuccessful a court hearing would be held.
In comparison, in the Manawatu-Wanganui area the Horizon Regional Council's ''One Plan'' drew 22 appeals and the Environment Court process took about two years to make provisional decisions.
Otago Fish and Game, while supportive of 6A's intentions, was one of the appellants. Chief executive Niall Watson said in a statement the relatively tightly focused appeal was designed to improve the workability of the objectives and policies in the plan, as well as making explicit what landholders could and could not do.
He hoped most, if not all, of the issues could be resolved through mediation rather than formal hearings.
