Some of the items listed in the [Index to names on WaterwayMap.org](https://waterwaymap.org/river/name-index/) are not in the expected order. Assuming the order is case insensitive, the order should be "Arroyo de la" ... "Arroyo de lo" ... "Arroyo del" 
Some of the items listed in the Index to names on WaterwayMap.org are not in the expected order.
Assuming the order is case insensitive, the order should be "Arroyo de la" ... "Arroyo de lo" ... "Arroyo del"