There’s going to be more elbow room in the writers room on most primetime series next season.

The cost-cutting crusade that has gripped the nets is hitting the scribe tribe particularly hard because there’s often more wiggle room in the number of writers working on a show than there is in other areas of a production.

There’s also a feeling among studio and net execs that there’s fat to be trimmed and that writing staffs have ballooned beyond necessity. This survival-of-the-fittest drama is unfolding during the next few weeks as the nets make their new and returning series pickup decisions on the cusp of their fall sked unveilings during the week of May 18.

Industry sources say studios producing skeins for Big Four nets are pushing for cuts of as much as 10%-15% in the writing budget for returning series, while new shows will start out with smaller staffs than first-year shows in recent seasons. Where skeins once had as many as 10-12 writers, not including the showrunner(s), the new norm is becoming six to eight.

A good example is NBC’s police drama “Southland,” which has a total of four writers, including creator/exec producer Ann Biderman. That’s partly because the show had only a six-episode order (on top of the pilot) for its late-midseason debut last month. But even now that the Warner Bros. TV/John Wells Prods. series been picked up for another season, it’s not expected to add too many more writers.

Cuts are being made on shows across the primetime sked, particularly on returning dramas a la CBS’ “Criminal Minds” or Fox’s “Bones.” CBS, the conglom that is most reliant on its mothership network as its profit engine, is said to be the most aggressive in scrutinizing budgets and writing staffs on all of its shows, including its crown-jewel “CSI” franchise.

The new era of austerity for the nets began with the jolt to the network system caused by the writers strike, and has only accelerated as the economy went into a tailspin last fall. That inescapable one-two punch has made the creatives — and their agents — more understanding, however begrudgingly, of the nets’ need to be hawkish on spending. Like so many areas of the U.S. workforce, TV writers in this economy are simply happy to have a job, tenpercenters say.

The nets are fearful that upfront advertising sales in the thick of the recession will come in far below last year’s haul of $9 billion across ABC, CBS, Fox, NBC and the CW. If the dire forecasts of a 15%-20% drop in upfront spending prove true, it will put a serious crimp in cash flow for the nets, unless that scatter ad sales market rebounds strongly later in the season.

Studios are hell-bent on bringing series budgets down below the $2.6 million-2.8 million per episode that has become the norm for hourlong dramas — or just over $1 million to $1.4 million for half-hours, depending on the format (single-cam or multicam) and star salaries — because of the diminishing returns in syndication and international markets.

As TV skeins now gain much more immediate exposure from online, DVD and paid download offerings, there’s no certainty a big syndication payday will offset all of the deficit spending racked up in a show’s first few seasons.

The networks are just as eager to see studios rein in budgets so that they in turn hold the line on the license fees they pay for programs, generally around $2.2 million-$2.4 million for dramas and $1 million-$1.2 million for half-hours. With so many nets and studios now under the same umbrella, the focus on costs is heightened, because every penny spent on production and license fees is coming from the same pot.

The upshot, industry insiders say, is that it’s going to be rough in the coming season for many writers, particularly the mid-level players who aren’t quite showrunner-status but are well past the entry-level stage.

Writers who are on staff earn a per-episode salary, plus a scribe is paid WGA minimums for every script (teleplay and/or story) he or she pens for the show. (A story and teleplay credit in the 2009-10 season will fetch $32,700 for an hourlong script; $22,233 for a half-hour.)

In recent years, the norm for a primetime series writing budget has been around $100,000-$120,000 per episode, not including showrunner fees or the cost of paying guild minimums. That number is expected to drop to the high five-figures for many shows this season.

If a show is under pressure to cut costs, the more experienced writers, who command $30,000-$40,000 an episode, are likely to be more vulnerable than the $15,000-$20,000 writers.

“If you’re a low writer and you’re good, you’ll probably survive because you don’t cost that much. For a lot of high-paid writers, it’s going to be, ‘We’re sorry but we’re letting you go,’ ” said a top lit agent who was in the thick of writer staffing deals last week.

And the annual raises or development offers that writers used to be able to count on after they’d performed well on a show for a season or two? They’re a thing of the past, at least for now.

“Flat is the new up,” the agent quipped about salaries for the coming season.

The big unknown in all of this is how the cuts will affect the quality of shows. Execs stress that making trims where possible on writing staffs help keep onscreen production values high. But the thinning of the scribe herd will undoubtedly put more pressure on showrunners, who might’ve otherwise delegated some rewrites and story-related tasks to their more experienced lieutenants.

The trend of shows adding “consulting producers,” who might write one or two scripts per season and offer their wisdom in the writers room a few days a week, will continue, insiders say. Consulting producers generally command about $20,000-$25,000 per episode, and have the freedom to work on other shows at the same time, unlike other staff writers.

As the biz grapples with a big wave of change, industry vets point to earlier eras of the biz when primetime skeins routinely had only few producers on staff and used freelancers to write most of the episodes.

And then there’s the “I Love Lucy” standard, where two staff scribes, Bob Carroll Jr. and Madelyn Davis, wrote virtually all of the show’s 181 segs.