Bulkhead repair is one of the most difficult projects to call on. In these cases, we are thrown into the same position as an auto mechanic, or your dentist. No one wants to call their dentist or mechanic – people are just not happy about the situation and why they have to do it. But it happens often and this is the prime time of year for these calls.
Why do bulkheads fail in February?
Bulkheads that are weakened by time, weather, and marine animals tend to fail in the cold months of winter. The reason is physics and the climate. The wind shifts direction and blows from the north and west during this time of year, which blows out all the water in our region of Louisiana. This leads to the lowest tides we experience all year. This extreme low tide situation means that the hydraulic pressure that the water exerts against the bulkhead drops, which was typically all that was holding up the weakened bulkhead. With the lower pressure on the water side of the bulkhead, the hydraulic pressure on the soil side of the bulkhead presses toward the water and the bulkhead fails.
What caused my bulkhead to become weakened?
A number of things can cause structural weakening of the bulkhead.
- Corrosion of the Tie-back Rods. Tie-back Rods anchor the top of the bulkhead and prevent it from leaning out. The rod connects the bulkhead to a piling driven into the soil side of the bulkhead as an anchor point – what is know as a “deadman”. The tie-back rods solidly attached the top of the bulkhead wall to the “deadman,” but failure of this rod means that the bulkhead is free to move.
- Rotting of the bulkhead sheeting. Many failing bulkheads we encounter are made of wood, particularly tongue and groove wood sheeting, and were installed 15+ years ago. The treatment of the wood sheets was leached out of the wood by wave action years before and the local marine life have had a buffet since then. Normal rot and the feeding activity of many marine organisms have caused the wood sheet to become perforated and weak. The first signs of this is small sinkholes which develop on the soil side of the bulkhead.
- Rotting of the Pilings. The typical lifespan of a marine piling treated to the 2.5CCA specification is about 25 years. A piling typically lasts longer than other parts of a wooden bulkhead because it can be treated to a greater degree. However, wave action will still leech out the treatment and eventually expose the piling to harmful marine life.
Can my bulkhead be repaired?
Typically no. The best thing to do is treat the symptoms if it is not too far gone. We want you to get the most life you can out of your existing bulkhead with as little out of pocket as possible. So what we recommend is not a repair of the bulkhead but a patch of the symptoms of its sickness.
- Repair any sinkholes so they will not return. We can tell you how and you can do it yourself.
- Monitor the stress level the bulkhead is under. Look for problems.
a. Has there been any movement?
b. Does it look like it is “bowing” out?
c. Does the line of the bulkhead appear to be straight or is it wavy?
If you are not seeing any of these symptoms, you may be ok. Call us and we will check it out for you – most properties we inspect do not need repairs immediately.
Replacement
Most of the time when a potential bulkhead failure looks possible, we recommend replacing the bulkhead with a new one. This is the last resort and we only recommend it when a failure seems likely. Steps to bulkhead replacement:
- Dig out soil behind the bulkhead to relieve pressure.
- Pull up old bulkhead and pilings.
- Drive new pilings, vinyl bulkhead sheeting, and walers. (check back to our Blog for a post on Bulkhead Anatomy)
- Drive new deadmen
- Install new tie-back rods
- Replace soil behind the bulkhead.
