In the best tradition of Socractic dialogue, Councilman Daniel “Doc” Satterlee, a retired LSU professor of poultry science, has posed for months something of a metaphysical question about traffic in Ascension Parish.

As some of his Parish Council colleagues have done, Satterlee has aired open skepticism of the value of traffic impact studies paid for by developers seeking approval for new housing in Ascension.

Satterlee, who represents the Prairieville area around La. 73, said he has researched traffic studies over the past 20 years for as many subdivisions along the highway as he could obtain and none, at the time, found an anticipated traffic impact.

Yet, state highway officials are wrapping up a $15.5 million project to widen the two-lane La. 73 to three lanes through one of Ascension’s fastest-growing areas.

Satterlee’s often-repeated question, hopefully leading students to the anticipated answer, has been this: “Why would you widen something if there’s no impact?”

Traffic impact studies are an important poker chip in improvements that parish planners try to make developers install, in particular off-site upgrades not directly connected to subdivisions. If enough impact is found, under parish rules, the parish and developers must negotiate mitigation.

Earlier this week, Satterlee and other council members learned why parish traffic studies don’t seem to pick up all the traffic effects others say new developments bring.

A new parish analysis suggests the parish’s own rules on those studies make them less likely to find enough traffic impacts to require negotiations on improvements.

Bob Horner, parish chief engineer, showed how three studies — a parish study, a state Department of Transportation and Development study and a study using a method known as area analysis — calculated traffic impacts for a theoretical 200-home subdivision proposed along La. 73.

The parish and DOTD studies — parish studies are modeled on DOTD’s — found a 51-second delay on La. 73. That’s enough to rate La. 73 with a “D” level of service, the third-worst rating. The new subdivision only added another second of delay, not enough to require any upgrades, those analyses found.

The more comprehensive study, which takes into account more intersections than the other two studies, found La. 73 has a 20-minute, 25-second delay.

That’s enough to rate La. 73 an F, the worst possible level of service. That level more closely matches what drivers experience, Horner told the Parish Council Strategic Planning Committee on Monday.

A new 200-home subdivision would add 37 more seconds in traffic delays, Horner’s analysis shows.

“I have heard our planning director — as a former planning and zoning commissioner myself before getting elected as a councilman — on more than one occasion say, ‘Traffic impact studies,’ quote-unquote, ‘aren’t worth the paper they’re written on,’ ” Satterlee told Horner after seeing his results.

“Now, with your analysis, Mr. Horner, I see why.”

In an email later this week, Planning Director Ricky Compton didn’t dispute Satterlee’s quote.

“I believe that until the parish revises the standards by which traffic studies are performed, it is highly unlikely that you will ever get a traffic study that declares that a development has negatively impacted the system,” he wrote.

Because voters rejected a 2012 plan that would have created a half-cent sales tax for road improvements, developers will have to provide the funding instead, Compton said.

“If the development community wants to continue to add additional traffic to the system, then that development community needs to accept that there is going to be a cost with helping the parish improve the system,” Compton said.

Some developers in Ascension declined to comment for this story or could not be reached by deadline. Ascension Parish developer Billy Aguillard said Friday he could not comment, either, because of his work on a parish subcommittee studying traffic impact fees for new development.

In Horner’s report to the Strategic Planning Committee, he made several suggestions. The parish, for example, should set minimum levels of service on roads and then developers must pay to prevent any diminishment of that level of service through per-lot fees.

Compton also said later this week that he favors impact fees on new homes, businesses and industry.

“We can debate till we are blue in the face on how much that fee should be, when it should be collected and how it should be spent. … What we can’t continue to debate, is whether or not it is needed,” Compton said.

Impact fees are charged on new development and used to compensate for the traffic impacts caused by the development.

Horner also has proposed more-extensive traffic analysis for all projects. Some of the smaller new subdivisions, which are the majority in Ascension, are exempted from the most-detailed traffic studies or any studies at all.

While council members on the Strategic Planning Committee said they like the idea of beefing up the studies, they aired concerns about requiring per-lot fees. They noted the parish’s long and contentious history with impact fees and the lack of council votes for the super-majority needed to pass impact fees.

“We start talking about impact fees, we’re going to line up the rooms again,” Councilman Dempsey Lambert said. “It’s going to fall off again. Let’s try to, let’s try to get the best we can with this.”

Councilwoman Teri Casso, who pushed to create the impact fee committee on which Aguillard is serving, said she favors voluntary fees while the council lacked the votes for impact fees. Some developers have agreed to those fees to pay for off-site mitigation.

In April, the developers of 343 new lots in the Pelican Crossing subdivision in Burnside agreed to $1,000-per-lot fees. The expected traffic impact, without the fees, would have led parish planners to recommend denial of the project, parish officials said.

The money will be put toward design work for a roundabout at the congested La. 44 and Loosemore Road intersection, a major commuter backup point for Pelican Crossing, Pelican Point and other areas south of Gonzales. Compton said other developers are considering similar voluntary fees.

But Councilman Kent Schexnaydre said even that method raises fairness questions. Builders of the far more common 20-lot and 40-lot subdivisions can’t afford a $150,000 turn lane.

“How do we actually get something that is real, that is going to assist us in improving or reducing the impact from traffic from the smaller developments without an individual impact fee,” Schexnaydre asked.

That question remains unanswered, but Horner has been directed to compile information to strengthen parish traffic studies.

Follow David J. Mitchell on Twitter, @NewsieDave.