The Houston Chronicle reports on the findings from an in-depth CEA analysis that details how the Gulf Coast Pipeline has boosted economic activity by $2.1 billion in Oklahoma and $3.6 billion in Texas.

An Oklahoma-Texas leg of the Keystone XL Pipeline produced economic benefits that support approval of a northern leg still subject to hot debate, according to an industry group.

The Consumer Energy Alliance, whose membership includes a number of major oil companies, commissioned a study on the economic effect of the 485-mile portion of the Keystone pipeline known as the Gulf Coast Extension, which runs from a pipeline hub in Cushing, Okla., to Nederland in Jefferson County. It opened earlier this year.

The study found that during construction, Trans -Canada Corp. – the company behind the pipeline – spent $6 million each month directly with local businesses in Texas and Oklahoma.

The project required $2.3 billion in private-sector investment and the work of more than 4,800 people, researchers wrote.

The Maguire Energy Institute at Southern Methodist University in Dallas prepared the study for the Consumer Energy Alliance, which lists among its members energy companies including Anadarko Petroleum Corp., BP, Exxon Mobil Corp. and Shell Oil Co.

The report argues that the country lacks the pipeline capacity to support booming North American energy production and says the growing use of railroads to ship crude is inefficient and unsafe.

Three of the four phases of the Keystone XL pipeline system have been built. Because the proposed northern leg from Canadian oil sands crosses an international border, it requires a State Department finding that it’s in the national interest.

Environmentalists and other critics have spent years fighting the pipeline, arguing that it has the potential for dangerous spills and that oil sands crude is especially harmful to the environment.

The Gulf Coast Extension crosses 24 counties, most of which are rural and have population growth that historically has trailed state averages.

“Against this backdrop of slow population growth and below-average per capita income, the Gulf Coast Project has been an important contributor to the economic health of many of the 24 affected counties,” the authors wrote.

In Oklahoma, the report says, TransCanada’s spending boosted economic activity by $2.1 billion, and in Texas, the project contributed $3.6 billion to the economy. They say the northern length could have similar big economic benefits to communities along its route.

Earlier this year, the Obama administration announced that federal agencies would have more time to weigh in on the project, essentially guaranteeing that a final decision won’t be made until after the November elections.

Some federal lawmakers have tried, so far unsuccessfully, to force a decision sooner.