The 2018 bill passed includes 4.1tn pesos (US$1.4bn) for transport infrastructure and 1.8tn pesos for housing programs.
So far this year, the government has invested 13.6bn colones (US$24mn) to upgrade various local airports and airfields throughout the country.
Senator Jorge Robledo accused prosecutor general Néstor Martínez of being involved in the Odebrecht bribery scandal and announced he will take this case and separate judicial bribery revelations to the Inter-American Commission on Human Rights.
The bill, which still needs to be approved by other committees, would allow PPPs for smaller projects.
The Brazilian highway operator was fined for failing to carry out repairs, clean lanes and install appropriate signaling.
Over the next three years, the country could obtain US$97bn in investments via PPP mechanisms, which have "enormous potential" for the local economy, according to a study by social development institute Idesa.