Morong River

{{Use mdy dates|date=September 2024}}

{{Infobox river

| name = Morong River

| native_name = {{native name|tl|Ilog ng Morong}}

| name_other = Morong–Teresa River

| image =

| image_size =

| image_caption =

| image_alt =

| map =

| map_size =

| map_caption =

| map_alt =

| pushpin_map = Luzon mainland#Philippines

| pushpin_map_size =

| pushpin_map_caption=

| pushpin_map_alt =

| subdivision_type1 = Country

| subdivision_name1 = Philippines

| subdivision_type2 = Region

| subdivision_name2 = Calabarzon

| subdivision_type3 = Province

| subdivision_name3 = Rizal

| subdivision_type4 = City/municipality

| subdivision_name4 = {{ubl|Antipolo|Teresa|Morong}}

| subdivision_type5 =

| subdivision_name5 =

| length = {{convert|10|km|mi|abbr=on}}

| width_min =

| width_avg =

| width_max =

| depth_min =

| depth_avg =

| depth_max =

| discharge1_location=

| discharge1_min =

| discharge1_avg =

| discharge1_max =

| source1 = Antipolo, Rizal

| source1_location =

| source1_coordinates=

| source1_elevation =

| mouth = Laguna de Bay

| mouth_location = Northern tip of the middle lobe of Laguna de Bay

| mouth_coordinates = {{coord|14.50336|N|121.25396|E|format=dms|dim:15000_region:PH_type:river|display=inline,title}}

| mouth_elevation = < {{convert|2|m|ft|abbr=on}} above sea level

| progression = Morong River–Laguna de Bay

| river_system =

| basin_size = {{convert|70.21|km2|sqmi|abbr=on}}

| basin_landmarks =

| basin_population =

| tributaries_left =

| tributaries_right =

| waterbodies =

| waterfalls =

| bridges =

| ports =

| custom_label =

| custom_data =

| extra =

}}

The Morong River ({{langx|fil|Ilog ng Morong}}), also known as the Morong–Teresa River, is a river system in Rizal, Philippines. It is one of 21 major tributaries of Laguna de Bay. It covers 14 barangays and stretches {{convert|10|km}} from Antipolo down to Teresa, Rizal, Morong, Rizal and finally to Laguna de Bay.

The Morong River sub-basin has a drainage area of {{convert|70.21|km2}}.{{Citation |last=Liongson |first=Leonardo |author-link=Leonardo Q. Liongson |author2=Guillermo Q. Tabios III |author3=Antonio Daño |editor-last=Lasco |editor-first=Rodel D. |editor2-last=Espaldon |editor2-first=Ma. Victoria O. |contribution=Laguna Lake’s Tributary River Watersheds |title =Ecosystems and People: the Philippine Millennium Ecosystem Assessment (MA) Sub-global Assessment |year =2005 |publisher =Environmental Forestry Programme, College of Forestry and Natural Resources, University of the Philippines Los Baños |url=http://www.millenniumassessment.org/documents_sga/Philippine%20SGA%20Report.pdf |format=PDF}}

On 1991, a study noted that eutrophication in Laguna de Bay could be attributed to nutrients brought to the lake as a result of the tremendous deterioration of the Morong River and the San Pedro River. In the case of the Morong River, this increase was said to be a result of draining effluents from hog farms.{{Citation | title = The Laguna de Bay Masterplan | year = 1995 | url = http://www.llda.gov.ph/masterplan.htm | access-date = September 30, 2007 |archive-url = https://web.archive.org/web/20070929113747/http://www.llda.gov.ph/masterplan.htm |archive-date = September 29, 2007}}

A 1994 cleanup drive initiated by the Laguna Lake Development Authority in cooperation with the local communities and local government units of Antipolo, Morong, and Teresa removed some seven truckloads of garbage and cleared a {{convert|3|km|adj=on|spell=in}} portion of the river from water lilies blocking the waterway.{{Citation|last=Angeles |first=Fernan |author-link=Fernan Angeles |title=LLDA leads Rizal river clean-up drive |newspaper=Manila Bulletin |date=June 18, 2004 |url=http://www.mb.com.ph/issues/2004/06/18/BSNS2004061812129.html |url-status=dead |archive-url=https://web.archive.org/web/20051204010512/http://www.mb.com.ph/issues/2004/06/18/BSNS2004061812129.html |archive-date=December 4, 2005 }}