Friday, June 15, 2012

Flood Wall FAQs

Frequently Asked Floodwall Questions

Q. How many miles long is the floodwall? 
A. North side of James is 4,277 feet long and protects 150 acres of Shockoe Valley. The south side is 13,046 feet long and protects 600 acres. The northside floodwall extends from 12th and Byrd St. to 21st  and E. Cary St. The southside floodwall extends from Goodes St. west to just west of the Manchester Bridge 

Q. What is the highest point of the floodwall? Where is it? What is the lowest point of the floodwall? 
A. The northside wall is between 15 and 25 feet high with the lowest point under the I-95 James River Bridge in Shockoe Bottom. The tallest structure on the southside is the Gravity U-wall just west of the Mayo Bridge which is 43 feet from the top to the river’s edge. This is the lowest point along the south side floodwall.

Q. What material is the floodwall made of? 
A. Richmond's floodwall was completed in 1995. It's made of 22,000 cubic yards of concrete, 1,050 tons of reinforcing steel and 55,000 linear feet of steel piles.

Q. How many staff people work on the floodwall year round? 
A. The current staff is 5. General duties of staff: Preventative maintenance and operation of the floodwalls, canals and Bosher’s Dam Fish Ladder, landscape maintenance in warm weather months and repairs as needed.

Q. How often is Richmond’s floodwall tested? 
A. Road Closures are tested once a year.

Q. When was the last time there was a flood in the city of Richmond? 
A. The last significant floods occurred in 1996. The Blizzard of 1996 struck the Mid-Atlantic region in January, depositing a record amount of snowfall. Within two weeks of the paralyzing blizzard, a major rainstorm blanketed the area. The combination of warm, humid air and heavy rainfall melted the snow at an unprecedented rate. In a little more than a day, 2 to 5 inches of water from snowmelt combined with 2 to 5 inches of rainfall to create massive floods. The James River rose to 22 feet. Seven months later, rains from Hurricane Fran pushed the levels back up to 23.8 feet.

Q. How often are the pump stations checked? 
A. The stations are checked daily and the pumps and related equipment are inspected and operated monthly.

Q. What grade did the last floodwall inspection receive? 
A. The ratings are; Acceptable, Minimally Acceptable, and Unacceptable. The last inspection reports received gave the Minimally Acceptable rating which is standard.

Q. Is the Army Corps of Engineers the only certifying organization for the floodwall? If not, what are the others? 
A. FEMA also requires the floodwall to meet certification for the Flood Insurance Rate Map (FIRM) for providing protection against the base. The City of Richmond received accreditation for the Local Flood Protection Project on March 19, 2010.

1 comment:

  1. more questions: How high must the river be for the gates to be closed? What is the maximum river level the wall can handle?