( CNN ) -- Two international bridges between Nuevo Laredo , Mexico , and Laredo , Texas , were closed Wednesday because of rising water on the Rio Grande , Laredo officials said . Laredo 's International Bridge I is one of four that connect the two cities , but because it has the lowest elevation it was closed , said Laredo spokeswoman Xochitl Mora Garcia . Officials are worried that the high water may damage the bridge and are removing steel canopy shades authorities believe add weight and stress to the span , the spokeswoman told CNN . Officials expect the bridge to be closed for at least three days , Mora Garcia said . The Rio Grande , which usually has a depth of 6 to 10 feet at Laredo , is expected to crest Thursday at nearly 39 feet , the spokeswoman said . A second crossing , the Colombia Bridge , was closed because the water is cresting there at a higher level , Mora Garcia said . The bridge will be closed until further notice . It will take about a day to remove the canopies at International Bridge I and another day to reinstall them after the high waters subside , Mora Garcia said . About 10,000 to 12,000 pedestrians and 12,000 to 14,000 noncommercial vehicles cross International Bridge I each day , Mora Garcia said . Laredo has a population of about 250,000 , but that typically swells to 350,000 to 400,000 as Mexicans come to the city to shop , visit family or engage in recreational activities , the spokeswoman said . The city is the nation 's No . 1 inland port , Mora Garcia said . International Bridge II and the World Trade Bridge will remain open . Laredo owns and operates the four bridges , Mora Garcia said . `` Pedestrians who have no other alternative to reach Nuevo Laredo are encouraged to return immediately or make arrangements to travel by vehicle by Bridge II , '' the city said in a news release . `` Bridge II will NOT accept pedestrians to return to Nuevo Laredo . Colombia Bridge and World Trade Bridge can accept pedestrians . '' In addition , buses from Nuevo Laredo will be transporting would-be pedestrians back and forth over Bridge II over the vehicle-only bridge . The arrangement was made between U.S. and Mexican officials and will remain in effect for the duration of the emergency situation , Mora Garcia said . Laredo was planning to open its emergency operation center Wednesday afternoon . Residents in the 100-year floodplain will be notified to evacuate if necessary , officials said . The Laredo Civic Center can be converted into a shelter , the city said . On Wednesday , Texas Gov . Rick Perry announced that he was sending vehicles , guardsmen , and rescue divers to the Laredo area . `` As South Texas continues to feel the effects of Hurricane Alex , we are closely monitoring a storm system that is expected to bring more heavy rains to the area and increase flooding along the Rio Grande , '' Perry said . Water service in Laredo will not be affected , but residents in Nuevo Laredo may have water service at 50 percent of the city 's operating capacity , Laredo officials said . Communities throughout northeastern Mexico have been flooded as a result of heavy rains spawned by Hurricane Alex nearly two weeks ago . In the city of Reynosa in Tamaulipas state , on the border with Texas , 23,000 people were in danger Wednesday because of flooding by the Rio Bravo , the government-run Notimex news agency said . Alex stormed onshore as a Category 2 Hurricane on June 30 , causing at least six deaths in Nuevo Leon state .
International Bridge I and Colombia Bridge connect U.S. , Mexican cities . Comment: They are two of four bridges connecting Laredo with Nuevo Laredo . The Rio Grande is expected to crest at nearly 39 feet Thursday .