As of 2015, RV dump stations are not typically free, but they generally cost less than $10 to use, notes Sanidumps. The price of the dump station reflects its location along with the type of features it has, such as tools to help clean up the area.
The waste water from an RV should always be drained properly. Empty the black water tank waste first before dumping the gray water tanks. Gray water generally has a mixture of soap that can help clean the sewer hose and flush out any remaining material.
Although the majority of RV dump sites require payment, there are some parks that offer free dumping and have limited availability, particularly for non-overnight visitors.