Add the rhubarb and water to a large saucepan. Simmer on medium heat for about 10 minutes stirring occasionally. It's done when the rhubarb falls apart.

Set a strainer set over a bowl. If you want a very clear syrup you can line the strainer with two layers of cheesecloth. Pour the rhubarb mixture into the strainer and press gently with a spoon to squeeze the liquid out. Save the rhubarb pulp for another use.

Measure the rhubarb liquid and pour it back into the sauce pan over medium heat and add an equal amount of sugar to the rhubarb. This should be about 3 cups.

Stir for 3-4 minutes until the sugar is dissolved, skim off any foam from the top. Store in a clean glass jar in the fridge for 1 to 2 weeks. I also like to freeze the syrup in ice cubes to use in drinks.