Lock and Dam No. 7

{{Infobox dam

| name = Lock and Dam No. 7{{cite web | title=The National Inventory of Dams (NID) | publisher=United States Army Corps of Engineers | website=nid.usace.army.mil | url=http://nid.usace.army.mil/cm_apex/f?p=838:4:0::NO | accessdate=26 Mar 2017 | archive-url=http://webarchive.loc.gov/all/20171019170502/http://nid.usace.army.mil/cm_apex/f?p=838:4:0::NO | archive-date=19 October 2017 | url-status=dead }}

| name_official =

| image = Lock & dam 7 barge 01.jpg

| image_size = 300px

| image_caption = Mississippi River Lock and Dam No. 7

| image_alt =

| location_map = Minnesota

| location_map_size = 300px

| location_map_caption = Location of the Lock and Dam No. 7 on the border of Minnesota and Wisconsin

| location_map_alt =

| coordinates = {{coord|43|52|01|N|91|18|26|W|region:US-MN_type:landmark|display=inline,title}}

| country = United States

| location = Winona County, Minnesota
La Crosse County, Wisconsin
near La Crescent, Minnesota

| purpose = Navigation

| status = In use

| construction_began = {{Start date and age|1933}}

| opening = April {{Start date and age|1937}}

| demolished =

| cost =

| owner =

| operator = 24px U.S. Army Corps of Engineers, St. Paul District

| dam_type =

| dam_crosses = Upper Mississippi River

| dam_height_foundation = {{convert|abbr=on|41|ft|m}}

| dam_length = {{convert|abbr=on|10860|ft|m}}

| dam_elevation_crest =

| dam_width_crest =

| dam_width_base =

| dam_volume =

| spillway_count = 2

| spillway_type = 5 Roller Gates
11 Tainter Gates

| spillway_capacity = {{convert|abbr=on|273000|acre.ft|km3}}

| res_name = Lake Onalaska
Pool No. 7

| res_capacity_total = {{convert|abbr=on|5000|acre.ft|km3}}

| res_capacity_active =

| res_capacity_inactive =

| res_catchment = {{convert|abbr=on|62340|mi2|km2}}

| res_surface = {{convert|abbr=on|13440|acres|km2}}

| res_max_length =

| res_max_width =

| res_max_depth =

| res_elevation = {{convert|abbr=on|636|ft|m}}[http://www.topozone.com/wisconsin/la-crosse-wi/reservoir/lake-onalaska/ Lake Onalaska] on Topozone.com

| plant_name =

| plant_coordinates =

| plant_operator =

| plant_commission =

| plant_decommission =

| plant_type =

| plant_hydraulic_head = 25

| plant_turbines =

| plant_capacity =

| plant_capacity_factor =

| plant_annual_gen =

| website =

| extra = NIDID# MN00587

}}

Lock and Dam No. 7 is a lock and dam located on the Upper Mississippi River at river mile 702.5 near the cities of La Crescent, Minnesota and Onalaska, Wisconsin. It forms pool 7 and Lake Onalaska. The facility was constructed in the mid-1930s and placed in operation in April 1937. It underwent major rehabilitation from 1989 through 2002. The lock and dam are owned and operated by the St. Paul District of the United States Army Corps of Engineers-Mississippi Valley Division.

The lock and dam system consists of a concrete structure {{convert|940|ft|m|1}} long with five roller gates and 11 tainter gates, a segment of earth embankment {{convert|8100|ft|m|1}} long from the dam to French Island separated by a concrete spillway {{convert|1000|ft|m|1}} long, and another embankment {{convert|2400|ft|m|1}} long from French Island to Onalaska which has a concrete spillway {{convert|670|ft|m|1}} long. The lock is {{convert|110|ft|m|1}} wide by {{convert|600|ft|m|1}} long.

{{cite web

|url=http://www.mvp.usace.army.mil/Missions/Navigation/LocksDams/LockDam7.aspx

|title=Lock and Dam 7

|publisher=United States Army Corps of Engineers

|accessdate=2012-08-19

}} The lock and dam is one of the most visited because of its proximity to Interstate 90, and is clearly visible to travelers crossing the I-90 Mississippi River Bridge.

File:Lock & dam 7.png