diff --git a/main.tf b/main.tf
index fd3946d..eda2c74 100644
--- a/main.tf
+++ b/main.tf
@@ -25,11 +25,14 @@ resource "google_dns_managed_zone" "peering" {
   visibility    = "private"
   force_destroy = var.force_destroy
 
-  private_visibility_config {
-    dynamic "networks" {
-      for_each = var.private_visibility_config_networks
-      content {
-        network_url = networks.value
+  dynamic "private_visibility_config" {
+    for_each = length(var.private_visibility_config_networks) > 0 ? [1] : []
+    content {
+      dynamic "networks" {
+        for_each = var.private_visibility_config_networks
+        content {
+          network_url = networks.value
+        }
       }
     }
   }
@@ -52,11 +55,14 @@ resource "google_dns_managed_zone" "forwarding" {
   visibility    = "private"
   force_destroy = var.force_destroy
 
-  private_visibility_config {
-    dynamic "networks" {
-      for_each = var.private_visibility_config_networks
-      content {
-        network_url = networks.value
+  dynamic "private_visibility_config" {
+    for_each = length(var.private_visibility_config_networks) > 0 ? [1] : []
+    content {
+      dynamic "networks" {
+        for_each = var.private_visibility_config_networks
+        content {
+          network_url = networks.value
+        }
       }
     }
   }
@@ -66,7 +72,7 @@ resource "google_dns_managed_zone" "forwarding" {
       for_each = var.target_name_server_addresses
       content {
         ipv4_address    = target_name_servers.value.ipv4_address
-        forwarding_path = target_name_servers.value.forwarding_path
+        forwarding_path = lookup(target_name_servers.value, "forwarding_path", "default")
       }
     }
   }
@@ -82,11 +88,14 @@ resource "google_dns_managed_zone" "private" {
   visibility    = "private"
   force_destroy = var.force_destroy
 
-  private_visibility_config {
-    dynamic "networks" {
-      for_each = var.private_visibility_config_networks
-      content {
-        network_url = networks.value
+  dynamic "private_visibility_config" {
+    for_each = length(var.private_visibility_config_networks) > 0 ? [1] : []
+    content {
+      dynamic "networks" {
+        for_each = var.private_visibility_config_networks
+        content {
+          network_url = networks.value
+        }
       }
     }
   }
@@ -142,11 +151,14 @@ resource "google_dns_managed_zone" "reverse_lookup" {
   force_destroy  = var.force_destroy
   reverse_lookup = true
 
-  private_visibility_config {
-    dynamic "networks" {
-      for_each = var.private_visibility_config_networks
-      content {
-        network_url = networks.value
+  dynamic "private_visibility_config" {
+    for_each = length(var.private_visibility_config_networks) > 0 ? [1] : []
+    content {
+      dynamic "networks" {
+        for_each = var.private_visibility_config_networks
+        content {
+          network_url = networks.value
+        }
       }
     }
   }