Tax, spend and elect is apparently the intent of Measure AA, a special parcel tax placed on the June 7 ballot of the nine Bay Area counties by a hitherto-unknown governmental agency. The ostensible purpose is to spend money extracted from taxpayers to reduce trash, improve water quality, restore fish and wildlife habitat, protect against floods and increase shoreline access.

Measure AA would levy a special parcel tax of $12 per year for 20 years on every parcel in those nine counties in order to receive $25 million annually for 20 years. It would require two-thirds approval by voters cumulatively in the Bay Area counties. We should reject Measure AA.

A parcel tax is the most iniquitous of all property taxes. A property tax is based upon the assessed market value of the owner’s property, including those parcels that haven’t been sold since Proposition 13 was enacted in 1978. Under Measure AA, therefore, every homeowner would pay the same tax as corporate property owners such as Chevron, AT&T, Salesforce, Facebook, Genentech, Oracle and Google.

Of course, the measure is supported by business groups such as the Bay Area Council and the Silicon Valley Leadership Group. Why not? It’s a regressive tax, levying the same amount on inland residential parcels as on owners of multimillion-dollar business properties on the bay, which are most subject to the promised flooding. And, properties on the shoreline of San Francisco Bay are almost entirely commercial and industrial businesses. Reduction in flood risk will be reflected in lower insurance rates and increased property values for the corporate billionaires.

A tax levied on property owners has been, and should be, proportional to the parcel’s value. That’s common sense, as evident in school bonds and municipal parcel taxes, which are calculated on the assessed value of each property, rather than as a flat tax.

Does any property taxpayer-reader identify the members of the agency that put this measure on the ballot, the San Francisco Bay Restoration Authority? They are elected officials from the nine Bay Area counties, but they’re not identified in the voter’s handbook, and they surely weren’t elected by voters to this new bureaucracy.

We should instead require taxation based on ability to pay and not a levy that disfavors some inland cottage owner to the benefit of a billionaire’s bay-side high-tech business campus.

Tell this new bureaucracy to start over. Voters should vote no on Measure AA.

Quentin L. Kopp is a retired judge of the San Mateo County Superior Court, a former member of the San Francisco Board of Supervisors, and former state senator representing San Mateo and San Francisco counties.