the ultimate flood prevention
1. What is the Knost Flood Wall™?
The Knost Flood Wall™ (“KFW” ) is a proprietary, patented, engineered wall system composed of a below grade footing and foundation and an above grade structurally attached block wall totally waterproofed from bottom to top. The below grade section has been common waterproofing practice for nearly 50 years and in combination above grade will protect existing or new residential communities, commercial buildings, shopping centers, etc. from flooding.
2. How are residential and commercial structures being protected from future floods today?
In much of the Gulf Coast area ravaged by Katrina/Rita flooding, homes and other buildings which are below the federal height guidelines are being raised a minimum of 2.5 feet. New construction also requires meeting the elevation requirements. Otherwise, the similar levees that failed are being rebuilt.
3. How is the Knost Flood Wall™ an improvement compared to the existing remedy of raising structures? Primary - prevents damage from flooding to homes, businesses, schools, refineries, etc.
The Knost Flood Wall™ offers many benefits compared to raising existing structures. Substantially lower cost is one of the primary benefits. The inventor has compared the estimated installed costs of the KFW versus elevating pier and beam houses excluding the costs of retrofitting all utilities etc., reflecting a minimum savings of 50% vs. raising for any given neighborhood.
Savings are much more substantial in neighborhoods of homes built on concrete slab or two stories. Fact is, the longer the KFW the greater the cost savings vs. raising.
Other benefits of the KFW include: less exposure to future wind damage compared to a raised structure; no need to finish-off the underside of a raised home; no likelihood of structural damage to an existing home during the elevation process; and increased security and sound abatement. Additionally, use of the KFW eliminates the need to build handicap access for raised properties.
4. Have there been any installations of the Knost Flood Wall™ to date?
No. The Knost Flood Wall™, invented by Mr. John O. Knost and owned by Reflections Design, LLC, only recently received its patent pending. Mr. Knost, a New Orleans resident with extensive executive and construction experience, is now exploring alternatives to capitalize on the value of his patent while at the same time helping to rebuild the Gulf Coast region in a safer, secure and more cost effective protection method.
5. How would you describe the Knost Flood Wall™ structure?
The system is comprised of a below grade continuous concrete footing of size determined by site conditions. A concrete foundation wall is attached on top of the footing that would vary in depth from a minimum of 4 ft. below grade or more depending again on the engineering dynamics. Appropriate expansion joints are installed and spaced as required. Four parallel rows of concrete blocks (6 in.x 8 in. by 16 in.) are secured along the top of the footing (on grade) to a height at least 1 foot higher than the FEMA requirement elevation. Soil conditions may require sheet or butt pilings, larger spread footing, etc.
It is of record that the KFW below grade waterproofing system has been proven successful and installed world wide for over 50 years.
The proven waterproofing membrane system is applied to the flood-facing below grade side of concrete foundation wall and construction is sequenced to allow the membrane to extend and continuously adhered, sandwiched in the middle of the above grade concrete block portion of the wall. Thus, from the very bottom of the below grade wall to the top of the block structure is near impermeable to rising water.
The waterproofing membrane is protected by a 22 ga. min. metal cap on the top of the block wall to protect the finished construction.
6. What type of pumping apparatus might be required with the Knost Flood Wall™, and under what circumstances?
Based on the amount of area to be protected by the KFW and available access to public collection for the French drain, properly sized and situated float activated, elevated solar powered pumps may be desirable for select applications.
7. How would vehicles and pedestrians access to and from the protected property?
Flood gates and/or doors installed to match the height of the wall, automatic or manual. Depending on the size of the area protected, paved emergency drive over berm(s) for use when the gates are closed. ( see drive over gates application herein)
8. How would any underground electric, gas, water, sewer and other utilities transit the Knost Flood Wall™?
Utilities can be run under the wall prior to its construction or through the wall using commercially available watertight sleeves.
9. What do you expect would be the ongoing maintenance requirement for Knost Flood Wall™ installation? What is the expected life?
Normal maintenance would include regularly scheduled inspections to monitor soil settlement, proper French drain functioning, general wall condition, testing of pumping apparatus, etc. all included in the design spec. Repairs would be made based on scheduled inspections. With the use of high density concrete and other premium materials, proven construction techniques with constant quality control, and a sound maintenance program, the KFW could be expected to perform as designed for a minimum of 50+ years.
10 What kind of conditions might be unsuitable for installation of a Knost Flood Wall™?
The KFW may not be well-suited in applications: 1.) in areas with a very high water table that severely restricts excavation pump out during construction, though this could be worked with some cost penalty; 2.) where above grade wall height exceeds 8 feet, a thicker wall with additional reinforcing steel would be an option; 3.) where access to the work site is restricted.
11. What level of structural and soils engineering have gone into the design of the Knost Flood Wall™?
A. Developmental engineering assures the design structure of the KFW is completely valid for the application intended. Site specific soils will dictate the physical size and depth of the below grade wall and footing and, determine if pilings are required. Normally expected costs for such construction is included in the cost comparison for the KFW vs. the cost to elevate homes.12. What kind of access across or through the Knost Flood Wall™ is included in the KFW cost estimate?
The estimate includes flood gates / doors, and, emergency berms.
13. Have you included costs for installation of pumping capability in the Knost Flood Wall cost estimate?
Yes.
14. What is the estimate of the annual cost of maintenance in your comparison?
This has not been determined or estimated, but could be expected to be minimal, and remain so as long as maintenance is performed when its needed as first identified through routine and regular inspections.
15. Does the Knost Flood Wall™ cost estimate include pilings under the footing?
A. The need for pilings under the KFW would be determined by the site soil conditions and footing size. In any event, assuming a site where pilings were required to be placed every 10 feet of wall length driven to refusal or 20 ft. deep, the cost impact would be minimal.
16. What specific types of site and soil conditions might be ill-suited for use of the Knost Flood Wall™?
Swamp areas, difficult site access, extraordinarily heavy utility lines through or under the KFW or where the soil conditions will not allow prudent below grade construction.
17. Has FEMA evaluated the KFW and if so, results.?
Yes, extensively.A letter received from FEMA states, ”if a community was interested in pursing this concept (KFW), the community could make application to the State of Louisiana for a mitigation grant to fund this project”. ( wall installation)
18. Has the U.S. Army Corps of Engineers reviewed the invention?
Yes. In a lengthy meeting with the Asst. Chief Engineer and staff, they can not be involved with what is considered to be “in the private sector”. Great review, positive comments and suggestions, but, the Corp is too concentrated on levees, canals, flood gates, pumps, MRGO, wetlands, etc. Their exact closing quote was, “the KFW is the backup to our levee system”.
19. Is there legislative assistance available to expedite the FEMA mitigation application and funding process?
Yes. The Honorable Senator Mary Landrieu’s Washington D.C. office has agreed to facilitate the funding procedure.