Will walking on sand help lower impact even more?

Sand walking. Walking on sand verses pavement can be better (as in safer) for your joints as sand can provide your joints with more cushion if you walk with the same impact you use on pavement. Both surfaces have their pros and cons. Walking on sand can also test your balance and lower-leg stability. Stay focused, though, because if you are not careful you could roll an ankle or tweak a knee.
Yes. Yes, soft sand will lower the impact of walking. It will also helps strengthen the core by promoting better balance. Walking is a wonderful exercise during pregnancy.