The bottom line. CBP is proposing to withdraw the international airport designation of Chalk Seaplane Base, now operating as Miami Seaplane Base, citing noncompliant facilities and insufficient business. Comments are due by October 20, 2026.
The U.S. Customs and Border Protection (CBP) published a notice of proposed rulemaking in the Federal Register on August 21, 2026, to remove Chalk Seaplane Base from the lists of designated international airports in 8 CFR 100.4(b) and 19 CFR 122.13. The proposed change would affect both customs and immigration processing at the seaplane base on Watson Island in Biscayne Bay, near Miami, Florida.
The seaplane base, which has not processed international arrivals since May 15, 2021, would be removed from the regulations under the authority of 19 U.S.C. 1644a and section 234 of the Immigration and Nationality Act. CBP said the facility has not met its regulatory and security standards and that the volume of business does not justify maintaining inspection equipment and personnel at the location.
History of Operations
Chalks Airline built the seaplane base in 1926 and operated international flights from the location until 2007, when the U.S. Department of Transportation revoked the airline's flight authority due to safety issues. Nautilus Enterprises purchased Chalks Airline in 2012, acquiring the rights to operate the base.
Until May 2021, CBP processed passengers for up to 11 weekly flights, typically originating from the Bahamas with about five passengers each. CBP officers traveled from the Miami Seaport, located three miles away, to process passengers at the base.
Noncompliant Facility
CBP said it engaged in multiple rounds of communication with Chalks Airline management beginning in 2013 regarding facilities that did not meet CBP's regulatory criteria for safety and security. On August 6, 2019, CBP sent a formal notice requiring a compliant facility within 12 months, warning that passengers and crew would otherwise be transported under safeguard to Port of Miami facilities at the operator's expense.
After the COVID-19 pandemic delayed enforcement, CBP notified Chalks Airline on April 15, 2021, that it would begin denying permission to land to all aircraft operators from foreign areas on May 15, 2021. Since that date, CBP has directed international flights to land at Miami International Airport or Fort Lauderdale-Hollywood International Airport instead. In April 2022, Chalks Airline said construction of a compliant facility had not started and would take about two years to complete; CBP said no progress has been made to date.
Insufficient Passenger Volume
CBP cited the low volume of business as an additional basis for the proposed withdrawal. Before 2021, the agency processed only about 55 passengers weekly at the base from a single international destination. Miami International Airport, located three miles away, offers a reasonable alternative for flights that would otherwise be processed at the seaplane base.
The proposed rule would not affect the geographic boundaries of the Miami port of entry listed in 19 CFR 101.3, according to CBP. The agency said the revocation would not result in a significant reduction in CBP services in the area because two suitable international airports are nearby.
Regulatory Status
The Office of Management and Budget has not designated this rule a significant regulatory action under Executive Order 12866. CBP classified the proposal as a deregulatory action under Executive Order 14192, estimating the economic cost to all parties to be zero since the base has not been used for international flights for several years.
CBP certified that the proposed rule does not have a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act. The Secretary of Homeland Security notified Congress of the intended designation withdrawal on November 25, 2025, fulfilling the requirements of 19 U.S.C. 2075(g)(2) and section 417 of the Homeland Security Act.
What This Means Right Now
International flights that previously landed at the seaplane base will continue to be processed at Miami International Airport or Fort Lauderdale-Hollywood International Airport.
The seaplane base may continue operating for non-international flights; only the international airport designation is proposed for withdrawal.
Interested parties may submit comments through the Federal eRulemaking Portal at www.regulations.gov, referencing docket number USCBP-2026-0892, until October 20, 2026.
If finalized, the rule would remove the entries for the seaplane base from the lists of designated international airports in both the immigration and customs regulations.