If things had gone according to plan, King County would have joined the bright new world of nonstop, image-flipping electronic billboards last week. That’s when the County Council planned to pass an ordinance, pushed by the dominant local outdoor-advertising firm Clear Channel, that would have opened the county to the digital billboards that have become unmistakable fixtures and political flashpoints in Los Angeles and many other cities.

But the council decided to postpone the vote for at least two weeks and send the measure back to committee for some tweaking. The reason given: Council staff hadn’t given sufficient public notice. This was true; the bill had moved with unusual dispatch and unusually little notice toward passage. Officials of three cities prospectively affected by the ordinance complained that they hadn’t learned of it until the last minute, and the leading local billboard critic didn’t find out until after the council took final public comment on June 6. No citizens showed up to speak except two Clear Channel executives.

But it’s not the whole story. In the wake of that cozy hearing, a slew of questions have arisen about the wisdom of going digital — issues that the council hadn’t considered as it moved to embrace this most visible of digital revolutions.

One obvious question: Would this lead to the sort of outsized, overlit, manically flashing and animated billboards that line Interstate 5 near Fife and Milton? Not nearly, as Clear Channel takes pains to point out. The I-5 flashers stand on Puyallup tribal land and wouldn’t be allowed by other jurisdictions. The new ordinance would merely allow Clear Channel to convert the 21 billboards it now has in the unincorporated country to “static” electronic signs. That is, static to a point: They could, and would, change images every eight seconds, the maximum allowed for digital signs in most jurisdictions including Seattle and, more broadly, Washington state. Imagine giant roadside computer screens showing an endless succession of pop-ups.

Some studies have found that this creates enough driver distraction to cause more accidents. Other studies find no increase in the accident rate, and others find more accidents with any kind of billboard.

There’s also some debate as to how effective the fast-flicking images are as advertising. What’s certain is that they’re marketing manna for the self-described “out-of-home” advertising industry. “Advertisers are encouraged to approach digital outdoor as an entirely new media form,” Clear Channel urges in its Seattle media kit.

Indeed. If the giant printed wallscapes described in a previous Crosscut report could be called billboards on steroids, then these are billboards on amphetamines. The company markets its “Seattle” electronic boards (so far just five, all of them in Kent, the only local jurisdiction that’s approved them) less as signs than as out-of-home TV commercials. Join the rotation and “your ad will be seen 4,810 times per day continually 19 hours per day. Generating 134,680 advertising spots over a 4-week period.” And that's just with five sites. Imagine the 21 billboards in unincorporated King County or the 520 in Seattle being transformed into giant televisions showing eight commercials per minute to viewers who can’t change the channel. You can bet the clever folks at Clear Channel do.

The company's strategy for getting this region to go digital seems to be to build on successes, one jurisdiction at a time. Clear Channel persuaded Kent officials by offering to air their emergency alerts and public-service messages. Kent’s police and Human Services Commission say they’re delighted with the results.

That helped sell the idea to King County Councilmembers Jane Hague and Larry Phillips, who sponsored the measure. “I particularly like the public safety aspects,” says Hague. “I also like the cost savings for Clear Channel.” (For the record, state public-disclosure filings show that Hague and Phillips have been the biggest recipients of Clear Channel campaign donations on the County Council. Since 2003 the company has given Phillips $3,000. Hague has received $3,850 from Clear Channel, its Seattle outdoor operations president, Olivia Lippens, and Lippens' husband.)

Hague and Phillips also laud the environmental benefits of going digital, benefits that Lippens took pains to point out at the June 6 hearing. Changing out images remotely every eight seconds, rather than on site every month or two, will “eliminate vehicle trips and thousands of pounds of paper and vinyl,” said Lippens. “This seems to be a logical and sensible way to embrace technologies as they evolve — a way to keep up with the times.”

Lippens didn’t mention, and the County Council and staff never asked about, the other big variable in that environmental calculation: the digital billboards’ energy consumption. When I asked Clear Channel’s corporate headquarters how much that is, and how it compares to the energy use of conventional painted or printed billboards, the company didn’t provide any data. Instead its spokesperson forwarded a recent study funded by the Outdoor Advertising Association of America, which found that operators of digital billboards have reduced energy consumption by 40 to 61 percent in the last four years, mainly by reducing unnecessary brightness at night and replacing the air conditioners used to cool their electronic controls with fans.

In the absence of industry reports, the most oft-cited study of e-billboard energy consumption is one done by urban planner Gregory Young with support from the Philadelphia advocacy group Society Created To Reduce Urban Blight, or SCRUB, “the Public Voice for Public Space.” Young found that digital billboards in Florida used 23 times as much electricity as conventional boards lit at night by halide lamps; in California, they used nine times as much. Compared to the average American home, the flashing signs used 15 times as much electricity in Florida and six times as much in California. That’s despite the fact the digital boards’ LEDs are much more efficient than halides. But the digitals have thousands of LEDs (versus, typically, just four halides), and they must crank up their power highest during the day, in order to compete with the sun.

The e-boards put out a correspondingly high measure of light. Light output, or luminance, is commonly measured in nits, which equal one candle or 12.6 lumens per square meter. Ambient roadway illumination is about one nit; sunlight is 6,500; conventional illuminated billboards average 124. The Outdoor Advertising Association recommends that operators keep digital billboards below 350 nits to avoid light trespass, but one study found actual output in sunny weather of up to 7,000 nits. Manufacturers trumpet capacities of up to 13,000 nits.

The King County ordinance doesn’t pick nits; it wouldn’t regulate light output directly. Instead it would limit illuminance, the amount of light cast upon an object at a given distance — in this case 250 feet — to “three-tenths of a foot candles [sic] above ambient light.” This indirect measure is more difficult to compare to other light sources than simple output, and may be more difficult for inspectors to monitor. But it’s the standard recommended by the Outdoor Advertising Association, and by Clear Channel.

Lippens assured the council that Clear Channel “self-regulated” to avoid lighting abuses and safety impacts. Paula Rees, a Seattle-based environmental designer who’s emerged as the leading local critic of the billboard industry, calls that claim “unconscionable.” In a letter to the council, Rees decried “the hollow promises and damage done to communities” by “monopolistic mega-media companies” such as Clear Channel.