In a heavy pot or dutch oven, add the rhubarb, sugar and water. Bring to a boil over medium high heat. Once boiling, reduce heat to low, Cook until the rhubarb is soft, about 20-25 minutes.
Use a fine mesh sieve to strain the mixture into a bowl, using the back of a spoon to press out all the liquid. Transfer to an airtight container.
Store in the refrigerator until ready to use
FOR THE RHUBARB LEMONADE:
In a large pitcher, add the cooled rhubarb simple syrup, lemon juice, and water. Stir.
Serve and enjoy!