The basic problems are 1) that this will be a 14 acre stadium on a 17 acre site, relying on off-site parking using parking lots from local businesses as well as street parking, and 2) The stadium will share the one parking lot for 3000 cars with Great America, which means that GA will have to close on game days and will need to be compensated.
To our knowledge, the Santa Clara stadium site will be the only NFL stadium site with such inadequate parking. 17,000 -20,000 cars will be parking offsite, there will be street closures, and residential neighborhoods will be cordoned off to prevent fans from taking up all of the street parking. Residents will have to show i.d. to get to their homes.
After 3 years of studies, there are no concrete plans in place for offsite parking.
That's not to mention the gridlocked traffic at intersections in Santa Clara, Sunnyvale, San Jose, and Milpitas, the noise, the tailgating mess in office building parking lots, etc.
The 'rush to woo the 49ers' that GA alleges is correct.

SCT-

Aren't there thousands of parking spots in nearby office building parking lots? A 5PM weekday night game would be difficult, but would a gameday Sunday be any worse than an average weekday?

As for NFL stadium sites with inadequate parking--to my knowledge, there's quite a few places...

The Bears have a lottery for their limited on-site parking spots. If a season ticket holder loses the lottery, they're paying double/triple for a scalped parking pass, parking off-site and taking a bus, or taking mass transit.

The Packers have very little parking of their own--all by reserved prepaid pass. Every time I've been there, I've had to park at the K-Mart or on someone's lawn. Friends who live up there with season club seats say they're on a waiting list for passes.

The Lions have you park all over the downtown area, as well as at the Eastern Market, as the Lions and Tigers-controlled lots aren't nearly enough.

I've parked off-site (by requirement or choice) in Minnesota, Denver, San Francisco, Oakland, Seattle, Miami, Cincinnati, Cleveland and Atlanta. By comparison, Houston, Arizona, Meadowlands and Philly had plenty of authorized parking.

Not saying a Santa Clara stadium is or isn't a good idea--I'm neither a resident nor a 49ers fan. But there are certainly current NFL stadiums in parking-deficient locations.

The stadium will be a fairly significant disaster for Santa Clara residents. Far too many liberties with the truth have been taken. Suburban stadiums have, overall, been very bad for the community. Santa Clara does not have a large enough police force even if every officer is present for game day; the city will be on the hook for millions in creating a regional task force. The city's fire and emergency forces are not adequate for a facility this size. Our garbage rates are going up and the stadium will generate 30 - 40 tons of garbage every game day. Other cities have tremendous problems with drunk driving, fighting, and alcohol-related medical emergencies. These things are bad for the community and very expensive to deal with. The stadium is sold to us as using no taxpayer money, and no new taxes, but redevelopment money IS taxpayer money. A new tax on hotel stays IS a new tax. This deal is toxic for the citizens of this city.

Mark-thanks for the info. on other stadiums.

The Santa Clara site is a bad idea for many reasons. Unlike Candlestick (49ers home now) and the Coliseum (Raiders home now) there is no direct freeway access. Surface streets with lots of stoplights will need to be used, and the EIR predicts gridlock at many many intersections in 4 cities, as people get off of freeways and have to travel to the stadium. Sunday traffic now is nice - and that's how Sundays should be. People should be able to have company, go to church, shop, run errands etc. without the gridlocked traffic that we routinely experience on weekdays at rush hour. Residential neighborhoods near the stadium will be cordoned off and people will have to show i.d. to get to their homes. Residents will be stuck in major traffic jams going to/from home, which represents a loss of use of their properties. (one intersection predicted to be at a value of 'F' (complete gridlock) has a hospital). Many residents fear a loss of property values as a result (and people here pay a lot for their property, even for something very small). Tailgating will not be contained within a fenced area - there's very little onsite parking (and part of it will be in a garage) - so the trash, public drinking, noise from boomboxes, smoke from grills, will occur wherever fans park. And then there's the urination problem with tailgating in office building parking lots-there will need to be port a johns. The mess to be dealt with just keeps on growing.
The city has had 3 years of studies to come up with a solution to the parking problem, and all they've done is wave their hands and say 'there's spots available'. Many of the companies are high tech companies-and those types of engineers do work on Sundays. Weeknight games just won't happen-who will pay the salaries of employees sent home at 3 pm so that fans can use parking lots?
We have a selfish city council majority that wants to ram rod this through before Nov when some of them are termed out. The 49ers announced plans to come here within days of the Nov 2006 election that installed a 49ers-favorable city council majority. They have voted yes on everything the 49ers want.
We now have a campaign by the 49ers of deceit-because of freedom of speech, they can say anything they want in campaign materials. We also have a 49ers sponsored ballot measure that does not disclose the stadium costs, and a ballot question written by a city council member that also does not disclose the costs, and a city attorney's summary that does not disclose the costs. We are being manipulated. The ballot question, summary, and measure all read like an advertisement for the 49ers stadium. Reality is quite different-the loss to our city's budget of $67 million, the $114 million in public funds being given, and the $330 million that our city's agency The Stadium Authority has to raise from high risk sources like personal seat licenses and naming rights - aren't mentioned in any of the ballot materials, courtesy of the 49ers and our city council majority (who are campaigning for the 49ers).
I know many many people here who are absolutely disgusted with the 49ers, the NFL, and our city council majority as a result of the stadium issue. If the stadium was such a good deal for our city, then why are the 49ers hiding the costs? Why are they spending boatloads of money trying to convince us to give them $444 million plus a loss to our General Fund (and BTW, the city's consultant predicts a 2 to 1 loss to our city's budget from this project, that doesn't even count the $67 million loss to our General Fund as property taxes are diverted towards stadium construction).

I'd add San Diego to that list: I had to park in a residential area a mile from the stadium the only time I've been to a football game there.

The group opposing the Santa Clara stadium, Santa Clara Plays Fair, has a new website with loads of new information. Please check it out:
www.santaclaraplaysfair.org