Modern thermal or nuclear plants need cooling water from river or sea. Therefore an intake pond for the water delivery system is a requisite component where sediment frequently deposits. An impinging jet is a functional measure for sediment re-suspension and a precaution against sediment deposition. This paper predicts the consequences of this new measure using theoretical analysis and laboratory experiments. The jet diffusion discharged into an ambient flow field, and the jet velocity at bottom, are predicted by the governing equations using an integral method. Equilibrium scour is obtained after the process of scour asymptotically finished for a limited depth sand layer. The non-dimensional equation derived can predict well the particle re-suspension. Critical jet condition is obtained for the sediment re-suspension by experiments. The effect of the jet angle and jet height on sediment re-suspension is also included and discussed. The results obtained for the scour to a limited sand bed by an impinging jet through cross flow is especially significant to the engineering design of intake ponds and culverts etc.