If you do not inspect and maintain the bridges on your rural property, you are putting yourself and others at risk says New Zealand’s leading farm consultants, AgSafe NZ.
Most bridges on private rural properties don’t specify live load carrying capacity or overweight ratings and often have very little (or no) design and construction records. And because of the cost required, they are typically never inspected.
Users of bridges on private property put themselves at risk if the bridge’s strength and weaknesses, vehicle types, loads and axle weight restrictions of vehicles, as well as speed, aren’t defined.
“To ensure the safety of bridges on private property it is very important to get an engineer’s evaluation of the weight rating and safety of the bridge,” advises Jim Findlay, Rural Consultant for AgSafe New Zealand Ltd.
A common issue is that a lot of bridges are old and were originally built to take smaller vehicles and equipment and can’t handle the modern weights of the vehicles and equipment that we use today.
A way to check the age of a bridge is to look for the bridge builder’s stamps or markings on or around the bridge as these will include the dates the bridge was built. If not you may be able to contact the builder and see if the bridge has been rated for maximum load.
“The wheelbase of loaders, machinery and other equipment are often broader than the bridge’s beams,” adds Jim.
It’s important to note a bridge’s weight-bearing capacity can’t be guessed out by visual inspection. You need some expert and background knowledge to get an accurate assessment. “If there’s any doubt, consult an expert,” comments Jim.
You can, however, check the condition of the bridge. Check if there are any rotten boards, if there is good drainage, the coatings on steel structures are in good condition, concrete deterioration, decay in timber piles, rusted or corroded fixings and impact damage from vehicles.
Having regular inspections by a qualified professional of all bridges longer than three metres and higher than three metres on your farm can drastically reduce the risk of accidents.
You can contact your city, regional or district council to find out their rules about who regulates the bridging of rivers and streams within the region under the Resource Management Act 1991.
Contact AgSafe NZ Ltd:
Phone: 0274 587 724