diff --git a/src/main/java/gov/usgs/earthquake/nshmp/netcdf/www/NetcdfService.java b/src/main/java/gov/usgs/earthquake/nshmp/netcdf/www/NetcdfService.java
index 72102fcfc77967f151592d3ec6da11738cd273fb..d00e8320822c0c6c9fd01f6b23b85b52cbe50b00 100644
--- a/src/main/java/gov/usgs/earthquake/nshmp/netcdf/www/NetcdfService.java
+++ b/src/main/java/gov/usgs/earthquake/nshmp/netcdf/www/NetcdfService.java
@@ -110,7 +110,7 @@ public class NetcdfService {
         geojson.add(feature);
       }
 
-      return HttpResponse.ok(geojson.toJson());
+      return HttpResponse.ok(geojson.build().toJson());
     } catch (Exception e) {
       return NetcdfWsUtils.handleError(e, SERVICE_NAME, LOGGER, urlHelper);
     }