2015 Inspection – 1999 Historical-Raven 405 – Lago Vista, Texas – Manhole


Raven Lining Systems

13105 E. 61st Street

Suite A

Broken Arrow, OK 74012

(918) 615-0020

Location: Lago Vista, Texas (20816 Dawn Dr.)

Owner: City of Lago Vista

Original Contractor: Lewis Concrete Restoration (formerly F&L Concrete)

Estimated Project Date: 1999

Age of Project: 16 years

Inspection Date: September 15th 2015

Type of Structure(s):

This study was completed on a single 4’ diameter manhole measuring a depth of 4’ at 20816 Dawn Dr. Lago Vista, TX. This manhole was precast with no resurfacing material. The manhole was located behind an office building with very little flow.

Condition of Structure(s):

The manhole was coated in 1999 with Raven 405 with an average of 125 mils. There were no visual defects or active leaks in the coating. During the original application of the Raven 405, the manhole rig was coated. Since then the ring has rusted to the point where the coating is no longer adhering to the ring. Raven recommended that the coating be terminated below the rig and a flexible chimney seal, such as Raven 581 is used to seal between the ring and chimney.

Structure Results: This manhole was on the east side of the parking lot and had three 20mm dollies glued to the coating and cored.

The resulting pulls were:

  • 656psi (85% substrate failure, 15% Adhesive failure)
  • 457psi (80% substrate failure, 20% Adhesive failure)
  • 497psi (75% substrate failure, 25% Adhesive failure)

Lago Vista Manhole 1999 Historical