Why is my player always on top of the river (water plug in) when walking?

so i placed a river on my landscape but everytime my player passes through it just walks on top of the river and not on the ground below the river but when my player jumps thats the only time it reaches the ground below the river then comes back up again on top of the river. unchecking the enable collision tick box on the river solves my issue with the player but it also loses water simulation effects coz i made my player to produce water rippling effects as he walks on water.