Keep America's Waterfronts Working Act This bill amends the Coastal Zone Management Act of 1972 to direct the National Oceanic and Atmospheric Administration (NOAA) to establish a Working Waterfront Grant Program. Under the program, NOAA may award grants to coastal states with approved working waterfront plans in place to preserve and expand access to coastal waters for people engaged in fishing, aquaculture, boat building, and other water-dependent businesses. In addition, NOAA is authorized to award grants to coastal states for the purpose of developing or revising working waterfront plans. States are allowed to allocate any grant money received to eligible local governments and other entities. Each state that is awarded a grant must contribute at least 25% of matching funds towards the total cost of the project carried out with the grant, subject to certain exceptions. The Department of the Interior must establish a Working Waterfront Task Force that will be designed to identify and address critical working waterfront needs with respect to cultural and economic importance, climate change and other environmental threats, and market conditions for water-dependent businesses.