WIFIA has strings attached, particularly for wastewater-treatment construction. Agencies that seek WIFIA aid for such projects are barred from also using tax-exempt bonds for the same jobs.

WRRDA also strengthens EPA's Clean Water SRF program, says Adam Krantz, National Association of Clean Water Agencies managing director for government and public affairs. For example, it gives local agencies up to 30 years to repay SRF loans. The limit now is 20 years.

The legislation has provisions that aim to accelerate Corps project approvals. For example, it says feasibility studies must be done within three years and cost no more than $3 million, with some exceptions. That would codify an existing Corps initiative. The measure also allows non-federal agencies and other entities to fund project studies.

Environmental groups worried about how earlier versions of the legislation treated project reviews. Scott Slesinger, Natural Resources Defense Council legislative director, says the final version is "slightly better" on that score than the bills that the House and Senate passed last year.