public void setWaterTransparency(float waterTransparency) {
        this.waterTransparency = waterTransparency;
        if (material != null) {
            material.setFloat("WaterTransparency", waterTransparency);
        }
    }
Sets how fast colours fade out. You can also think about this
as how clear water is. Therefore, use smaller values (e.g. 0.05)
for crystal-clear water and bigger values for "muddy" water.
default is 0.1f

@param waterTransparency the desired muddiness (default=0.1)
jme3-effects/src/main/java/com/jme3/water/WaterFilter.java