sentences:  On June 11, 2008, TxDOT announced they planned to limit further study of I-69 to existing highway corridors (US 59, US 77, US 84, US 281, and SH 44) outside transition zones in the lower Rio Grande Valley, Laredo, Houston, and Texarkana.Texas originally sought a public-private partnership to construct much of the route through Texas as a privately operated toll road under the failed Trans-Texas Corridor project.However, on June 26, 2008, TxDOT announced that they had approved a proposal by Zachry American and ACS Infrastructure to develop the I-69 corridor in Texas, beginning with upgrades to the US 77 corridor between Brownsville and I-37; the Zachry/ACS plan calls for the majority of the freeway to be toll-free; the only two tolled sections would be bypasses of Riviera and Driscoll.