diff --git a/R/constructNWISURL.r b/R/constructNWISURL.r
index 7f4957d707194bd6ecd0c8ca5ca7bbb7f1ef0d0f..3866056d20a5edf07a5aea0d0abb90454e117825 100644
--- a/R/constructNWISURL.r
+++ b/R/constructNWISURL.r
@@ -150,7 +150,12 @@ constructNWISURL <- function(siteNumber,parameterCd,startDate="",endDate="",
             rdb = "rdb,1.0",
             tsv = "rdb,1.0",
             wml2 = "waterml,2.0",
-            wml1 = "waterml,1.1"
+            wml1 = {if ("gwlevels" == service) {
+                "waterml"
+              } else {
+                "waterml,1.1"
+              }
+            }
           )