A wide-ranging plan to restore damaged Gulf Coast wetlands and other environmentally sensitive areas has received a boost with oil giant BP’s agreement to pay federal, state and local governments $20.8 billion to resolve civil claims stemming from its massive 2010 Gulf oil spill.

At least $6 billion of that total will help finance environmental and other related construction projects in the region, ENR estimates.

U.S. Attorney General Loretta Lynch, announcing the final settlement at an Oct. 5 press briefing, said, “This agreement will launch one of the largest environmental restoration efforts the world has ever seen.”

The settlement is spelled out in a consent decree lodged in federal district court in New Orleans. The agreement is subject to the court’s approval sometime after a 60-day public comment period.

A group of environmental organizations, including the Environmental Defense Fund, National Wildlife Federation and Coalition to Restore Coastal Louisiana, said in a joint statement: “Once the consent decree is approved, it will provide a steady funding stream to the Gulf—funds that are vital to the long-term ecological health of the region.”

Some of the funds can be used for a variety of purposes, but ENR estimates that at least $6 billion will be devoted to projects to improve the Gulf ecosystem and infrastructure. Environmental Protection Agency Administrator Gina McCarthy said that the funds would be distributed over 15 years.

The BP settlement payments will sharply increase regional restoration activities under way that are funded by an earlier Gulf oil spill settlement with Transocean Deepwater Inc.., the oil rig owner.

One of the BP settlement’s prime revenue streams for restoration work is $5.5-billion Clean Water Act penalties.. Under the 2012 federal RESTORE act, $4.4 billion of that total will be divided among Louisiana, Mississippi, Alabama, Florida and Texas.

The first portion of the $4.4 billion is $1.5 billion that will split evenly among the five states. Some of that money will go for heavy construction.

For example, Louisiana plans to use some of its allocation to help finance two large projects: the estimated $357.8-million Houma Navigation Canal lock complex and a $434.2-million Calcasieu ship channel project to close a connection between the channel and wetlands, says David Muth, director of the National Wildlife Federation’s Gulf Restoration Program.

A second portion, of about $1.3 billion, is to go for restoration work and will be controlled by a council composed of governors of the five states and heads of six federal agencies.. Muth says, “We would expect almost all that money to go to coastal construction and restoration projects.”

The BP settlement’s second major revenue stream is $8.8 billion for natural resource damages, which includes $1 billion that the company had committed earlier and $700 million for any needed restoration work that’s not currently foreseen.

The Deepwater Horizon Natural Resource Damage Assessment Trustee Council—which includes federal agencies and five Gulf states—on Oct. 5 released a plan outlining how it proposes to spend the $8.8 billion. The largest portion is $4.7 billion, including $4.3 billion for Louisiana, to restore wetland, coastal and other habitats.

Federal agencies include in the $20.8 billion total settlement $4.9 billion that BP has agreed to pay five Gulf states and up to $1 billion more to several hundred local governments in the region for economic damages incurred as a result of the spill.

Lynch said that the agreement is the largest settlement with a single entity in U.S. history. Federal agencies valued the agreement at $20.8 billion, or $2.1 billion above the $18.7-billion estimate for an agreement in principle announced in July. Lynch said the final number was “refined” from the earlier one and includes some funds BP had already committed to restoration.

Geoff Morrell, BP senior vice president for U.S. communications and external affairs, said in a statement that the final settlement doesn’t include any new money but reflects funds BP had spent or disclosed earlier.

He added that the agreement “resolves the largest litigation liabilities remaining from the tragic accident, providing BP certainty with respect to its financial obligations and allowing us to focus on safely delivering the energy the world needs.”