This Chargers stadium proposal? Watch it.

The Citizens' Stadium Advisory Group today, May 18, offered a plan for a new, municipally owned Chargers Mission Valley stadium that supposedly does not raise taxes and therefore averts any two-thirds public vote.

The plan is based on a dubious assumption: "The city and county are on solid financial footing," says the proposal. Oh? There is a $2 billion infrastructure deficit that is realistically double that. The possibility of a severe, long-lasting drought suggests tax money will have to be spent on providing more water, and water bills will also go up. There is a big pension deficit. The convention center is in financial trouble. And other problems loom.

Cocked eyebrows should greet this report. The plan does not rely on tax revenues from development, boasts the task force, but transient occupancy (hotel) taxes will contribute as a result of the building of a new hotel. Also, 75 acres will be sold to a developer. The task force is counting on $84.7 million coming in from a ticket surcharge and $26 million from a parking surcharge — both over 30 years. At least, a surcharge is paid by someone who is using the facility.

The task force boasts that it has "heard from numerous developers and private investors who want to fund all or part of the Mission Valley project." Oh? Where were those developers and investors earlier when the Chargers proposed developing Mission Valley? Is there enough water for the new development? Chargers spokesperson Mark Fabiani has pointed out that current Mission Valley residents are opposed to another development, and there is still a controversy about whether a plume under the stadium is a problem.

The city and county will each contribute $121 million, and supposedly the money will not come from a general fund.

The stadium will host non-football events, supposedly: monster truck jams, concerts, music festivals, soccer games, film showings, movie and TV shoots, religious events, rodeos — the list goes on. Petco was also going to bring in such events, and that has been a disappointment.

The Chargers will contribute $300 million, according to the plan. Previously, the team has been talking about putting in about $200 million. Forbes magazine estimates that the Spanos family is worth $1.26 billion, and almost $1 billion of that represents the value of the Chargers. Patriarch Alex Spanos is in his 90s and reportedly has severe dementia. Will three generations want to contribute this much of the family's wealth? The task force says that $135 million to $165 million will go to the Chargers from naming rights over 20 years. That would be subtracted from the $300 million, as would $15 million of naming rights remaining at Qualcomm, $25 million a year from "other," and $60 million from personal seat licenses (half of a total of $120 million).

If the team got $25 a year from the mysterious "other," the Spanos family might not be contributing anything, and would enjoy a huge boost in the value of the franchise. But can these be counted on? Doubtful. For example, the $120 million in personal seat licenses can be scratched right now. (Personal seat licenses are paid licenses to the holders to buy rights to a certain seat for a season.) Fabiani told me in 2011, "We do not anticipate selling [personal seat licenses] in any significant numbers in this marketplace." He has said the same thing on other occasions several times since then.

I agree. The cost of living in San Diego is 35 percent higher than the national average, but the median personal income is only 19 percent higher, according to Kelly Cunningham of the National University System Institute for Policy Research. Think of all the times citizens worried about a TV blackout because a game wasn't selling out. Erik Bruvold, head of the National University institute, believes the personal seat-license figure is doable, but I don't think he will find many agreeing.

The total cost of the stadium, including land, would be $1.3 billion. Bruvold has said that the six most recent NFL stadiums built or under construction would cost $1.5 billion in Southern California. But four of those stadiums are extravagant, says the task force.

The National Football League is committed to contributing $200 million. I presume that would be a low- or no-interest rate loan, but I would think it has to be paid back someday by somebody.

Another important point: Fabiani on March 16 on KPBS noted that 25 percent of the Chargerss’ economic support now comes from Orange County and Los Angeles County. Previously, numbers above 30 percent have surfaced. Logically, one must conclude that the Chargers would lose that support if a team or teams occupy the Los Angeles market, as seems probable now. The Chargers would be losing a lot of revenue — enough to make one wonder if building a San Diego stadium would be worth it.

Apparently, the city and county will hire consultants to vet the task force's work. But so-called consultants generally give the answers that the people paying their bills want to hear. Watch that one.

Watch one other thing: there could be a lawsuit against any proposal that goes forward. Such a suit or suits could delay construction and possibly raise construction costs.

This proposal is based on a lot of hopes and dreams. The mayor should come out and admit: taxpayers will have to pay for any new stadium — at least 65 percent.

While she was at Harvard, Judith Grant Long, now an associate professor at the University of Michigan, said in 2010 that, on average, taxpayers pay 78 percent and the team 22 percent of a stadium. The original estimates are always understated because the cities do not take such things as lost tax revenue into account.