Water Tank Level Sensor Design

I need a water level sensor/indicator that can work effectively with both above-ground and underground water tanks, which are primarily made of concrete. The sensor should provide a moderately precise measurement, such as to the centimeter.

Key Requirements:
- Compatibility with both above-ground and underground water tanks
- Ability to accurately measure water levels in concrete tanks to the centimeter

Ideal Skills:
- Experience in designing water level sensors
- Knowledge of materials and their impact on sensor performance
- Ability to develop a sensor that can accurately measure to the centimeter