(Adds water district response, paragraphs 13-14)
By Ian Simpson
WASHINGTON, June 27 (Reuters) - A $13.5 billion project to restore the Florida Everglades has had limited impact even as the embattled ecosystem faces threats from climate change and invasive species, a progress report said on Friday.
The Comprehensive Everglades Restoration Plan (CERP), started in 1999 to restore Florida's "river of grass" over 30 to 40 years, has been hindered by intermittent federal funding, the biennial report on the project by the National Research Council said.
Since the council's last update two years ago, CERP has had "modest restoration progress focused on the edges of the Everglades (and) considerable state effort to improve water quality," the report said.
The Everglades, an ecosystem of marshes, lakes, wetlands and tree islands stretching some 200 miles (320 km) from Orlando to Florida Bay, is about half its original size. Water now moves through a maze of levees, canals and pump stations.
Much of the water is diverted for industry and for millions of people in South Florida. The water that remains is heavily polluted.
The CERP has seen modest improvements at Picayune Strand in southwest Florida, coastal wetlands at Biscayne Bay and at the C-111 Spreader Canal in southern Miami-Dade County, the report said.
The CERP is not adequately considering the threat from climate change, with the Everglades facing rising sea levels caused by higher temperatures, it said.
Climate change is expected to increase demands for water from agriculture, straining supplies as population increases.
CERP lacks overall coordination to deal with non-native species, with a shortage of research on them and their impact, it said.
Such invasive plant species as melaleuca and Australian pine are infesting hundreds of thousands of acres (hectares) and fuel brushfires that destroy native plants.
Burmese pythons have become the Everglades' top carnivore, eating alligators and virtually wiping out other vertebrates, the report said.
The CERP involves 68 component projects overseen by the U.S. Army Corps of Engineers and the South Florida Water Management District. The goal is to reinstate the original water flow as much as possible, mainly by restoring undeveloped wetlands.
The Army Corps of Engineers and the water management district said separately that they welcomed the report.
The Corps said in a statement, "We recognize that as much progress as we've made in our restoration efforts to date, there's still more work to be done."
The National Research Council is part of the National Academies, which advise the U.S. government on scientific and technical issues. (Reporting by Ian Simpson; Editing by Bill Trott)