Preventing Pollution through Partnerships Act or the P3 Act This bill amends the Internal Revenue Code to allow state and local governments to issue green infrastructure bonds as tax-exempt private activity bonds. The bonds are not subject to the state volume caps that apply to certain tax-exempt private activity bonds. A green infrastructure bond must be issued as part of an issuance that requires 95% or more of the net proceeds to be used to develop, carry out, or certify approved green infrastructure projects. The approved projects are to construct, rehabilitate, maintain, or repair green infrastructure that has been certified by the state in which the project is located as effectively addressing nonpoint source pollution. "Green infrastructure" is infrastructure that preserves, enhances, or mimics natural infiltration, evapotranspiration, or capture of storm water.