Bolgenach

{{Short description|River in Germany}}

{{Expand German|Bolgenach (Fluss)|topic=geo|date=September 2011}}

{{Infobox river

| name = Bolgenach

| image = Bolgenach (Fluss).jpg

| image_size =

| image_alt =

| image_caption = The Bolgenach at Hittisau

| map =

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| source1_location =

| mouth_location = Weißach

| mouth_coordinates = {{coord|47.355031|9.9202|region:DE|display=it}}

| progression = {{RWeißach}}

| subdivision_type1 = Countries

| subdivision_name1 = Germany and Austria

| subdivision_type2 = States

| subdivision_name2 = Bavaria and Vorarlberg

| length_km = 29.9|length_ref={{GeoQuelle|DE-BY|GV}}

| source1_elevation =

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}}

Bolgenach is a river of Bavaria, Germany and Vorarlberg, Austria. It flows into the Weißach near Krumbach.