1. Pay up. Contribute what is necessary to meet promised benefits.
2. Right-size (reduce) benefits to what the employer is willing to pay.
3. ... or most likely, a little of both of the two above choices.
All these suggestions are correct. However it is difficult to do when only two out of three parties are represented at the negotiating tables. The politIcians and the pension beneficiaries have a lot of input but current and future taxpayers are rarely represented.