Allegheny River Lock and Dam No. 2

{{Infobox NRHP

| name = Allegheny River Lock and Dam No. 2

| nrhp_type =

| image = USACE Lock and Dam 2 Allegheny.jpg

| caption =

| location = 7451 Lockway W, Pittsburgh, Pennsylvania

| coordinates = {{coord|40|29|24|N|79|54|51|W|display=inline,title}}

| locmapin = Pittsburgh#Pennsylvania#USA

| built = 1932

| architect = Vang Construction Company

| architecture =

| added = April 21, 2000

| area = {{convert|8.8|acre}}

| mpsub = {{NRHP url|id=64500522|title=Allegheny River Navigation System MPS}}

| refnum = 00000396{{NRISref|2009a}}

}}

The Allegheny River Lock and Dam No. 2 (also known as the Highland Park Lock and Dam) in Pittsburgh, Pennsylvania is a lock and fixed-crest dam from 1932.{{Cite web|url=https://www.lrp.usace.army.mil/Missions/Navigation/Locks-and-Dams/Lock-Dam-2-Allegheny-River/|archive-url=https://web.archive.org/web/20161019162253/http://www.lrp.usace.army.mil/Missions/Navigation/Locks-and-Dams/Lock-Dam-2-Allegheny-River/|url-status=dead|archive-date=October 19, 2016|title=Lock & Dam 2, Allegheny River|website=www.lrp.usace.army.mil|language=en-US|access-date=2018-07-18}} It crosses the Allegheny River between the Pittsburgh neighborhood of Highland Park and the suburb of Aspinwall.{{Cite web|title=Allegheny River Lock and Dam Two|date=1990-08-30|publisher=Geographic Names Information System|accessdate=2010-09-22|url=http://geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO::P3_FID:1194851}} The lock and dam were built by the U.S. Army Corps of Engineers as a part of an extensive system of locks and dams to improve navigation along the Allegheny River. It is the most-used lock operated by the United States Army Corps of Engineers.{{Cite news|url=http://www.pittsburghlive.com/x/pittsburghtrib/business/s_699345.html |archive-url=https://archive.today/20120908040557/http://www.pittsburghlive.com/x/pittsburghtrib/business/s_699345.html |url-status=dead |archive-date=2012-09-08 |title=Corps shuts Highland Park lock for two weeks of repairs |last=Santoni |first=Matthew |date=2010-09-14 |work=Pittsburgh Tribune-Review |publisher=Trib Total Media |accessdate=2010-09-14 }}

Lock and Dam No. 2 is located about 6.7 Miles up the Allegheny River from the Point in Downtown Pittsburgh. Upriver from the dam, Allegheny Pool No. 2 has an average water elevation of 721 feet above sea level and extends about 7.8 miles upriver to Allegheny River Lock and Dam No. 3. Downriver is the Pittsburgh Pool with an average water elevation of 710 feet above sea level. Thus Lock No. 2 lifts and lowers boats about 11 feet between the pools.{{cite web |url=https://www.lrp.usace.army.mil/Portals/72/docs/navigation/AlleghenyRiverNavigationChart.pdf |archive-url=https://web.archive.org/web/20130317205840/http://www.lrp.usace.army.mil/Portals/72/docs/navigation/AlleghenyRiverNavigationChart.pdf |url-status=dead |archive-date=March 17, 2013 |title=Allegheny River Navigation Charts Allegheny River Navigation Charts|website=army.mil|access-date=10 April 2023|date=January 2004}}

The Pittsburgh Pool encompasses over 24 Miles of navigable water at about 710 feet of elevation. It stretches about 6.2 Miles up the Ohio River from the Emsworth Locks and Dam, 11.2 Miles up the Monongahela River to the Braddock Locks & Dam, and 6.7 Miles up the Allegheny.

The Highland Park Bridge crosses the river just above the dam. It was listed on the National Register of Historic Places in 2000.