As stated over half of the locks on the Mississippi are over 50 years old, and most were built in the 1930 and 1940's so it is unlikely that EMP would have caused much if any damage. Controlling the remaining bridges that cross the Mississippi might be of more importance however.
The Upper Mississippi runs 493 miles from its headwaters in Lake Itasca in Minnesota to Minneapolis, then 664 miles of navigable waterway through the states of Minnesota, Wisconsin and Iowa to St. Louis in Missouri. In Minnesota from Lake Itasca to Minneapolis there are 14 dams. From Minneapolis to Granit City, Illinois there are 29 locks and dams maintained by the US Army Corps of Engineers (two in Minnesota, seven on the Minnesota-Wisconsin border, three on the Iowa-Wisconsin border, eight on the Iowa-Illinois border, and nine on the Missouri-Illinois border).
List of crossings on Upper Mississippi:
http://en.wikipedia.org/wiki/List_of...sissippi_River
The Middle Mississippi is sometimes considered part of the Upper Mississippi. It starts in St. Louis and runs for 190 miles through the states of Kentucky, Missouri and Illinois to the confluence of the Ohio River at Cairo, Illinois.
The Lower Mississippi begins at Cairo and flows 1,000 miles to the Gulf of Mexico near New Orleans through the states of Arkansas, Louisiana, Mississippi and Tennessee. Unlike the Upper Mississippi there are no locks and dams on the lower section, although the river is constrained by a series of dykes and levees to control flooding and maintain navigable channels for river traffic.
List of crossings on Lower Mississippi:
http://en.wikipedia.org/wiki/List_of...sissippi_River
The Mississippi physically divides the eastern United States from the west, is a major artery for trade and commerce, and the Mississippi River Valley is one of the most fertile agricultural regions in the country. Therefore controlling it or part of it will be highly important to everyone in the Twilight War. According to Howling Wilderness the system of levees and dams on the Mississippi broke down after the breakdown of civil government in 1998-1999. The Mississippi River has also changed course by 2001, with its new mouth being through the Atchafalaya River which has radically affected the water table of the old delta. The fresh water supply to cities downstream of Baton Rouge has being contaminated with salt water. However it also implies that it was the Lower Mississippi that was the worst affected.
The Mid West and the Great Plains
MILGOV
MILGOV controls the Middle and parts of the Lower Mississippi. They control Cairo and in 1999 retook Memphis after eliminating the Overlord of Memphis and also defeated CIVGOV's 35th Engineer Brigade forcing it west across the Mississippi. MILGOV controls territory in Southern Illinois, Kentucky and Western Tennessee within 100 miles of the Mississippi River. They have an enclave in Louisiana and are fighting remnant New America forces in Arkansas and Southern Missouri. MILGOV also controls nearby Kansas, Oklahoma, Western Nebraska and parts of Northern Texas.
49th Armored Division: Oklahoma
85th Light Infantry Division (1st Brigade): Fort Beauregard, LA
95th Light Infantry Division: Oklahoma/Western Kansas
98th Light Infantry Division (2nd Brigade): Arkansas
194th Armored Brigade: Cairo, IL (detachment at Robinson, IL)
197th Mechanised Brigade: Memphis, TN
The School Brigade: Nebraska/Western Kansas
CIVGOV
CIVGOV controls Minneapolis and other parts of the Upper Mississippi in Minnesota, Northern Illinois and Western Wisconsin. CIVGOV also controls nearby Iowa and Eastern Nebraska and CIVGOV forces are moving west towards the Mississippi from the East Coast through the Cumberland Gap and the Ohio Valley.
84th Light Infantry Division: Minneapolis, MN
35th Engineer Brigade: Omaha, NE
184th Infantry Brigade: Moving west through Cumberland Gap
228th Infantry Brigade: Moving west along Ohio River
NEW AMERICA
New America has some strongholds in Arkansas and Southern Missouri and some sympathisers elsewhere.