Thaum Lub Yim Hli, kev loj hlob ntawm kev lag luam hlau downstream qeeb qeeb, cuam tshuam los ntawm kev loj hlob ntawm cov hlau tsim tawm thiab kev lag luam txhim kho, cov nqi hlau poob qis txhua hli. Mus rau lub Cuaj Hli, thaum tus nqi roj nyoos nce, cov nqi hlau tau rov zoo, xav tias yuav lig yuav tseem qhia txog qhov sib txawv me me.