Simply calculate how many days it takes to grow and how much it costs per day. Generally, a large bulldozer costs around 300 per hour, or around 3,000 per day including time. If your land is lower than the river, there will be very little investment. It is not recommended if it is above the river water level. In the later phase, water leaks were particularly significant. It doesn't have to be too deep in your home, around a meter is enough. If it's too shallow, the fish will be hot.
Rivers must be approved before they can be developed (just go to the village, the village will ask you to go to town to find someone)
You can get a loan if you own land and interest-free loans must be reported to the city. For ordinary three-year agricultural loans, you can directly apply for a loan from the Agricultural Bank of China.