Last week California’s Oroville Dam, the tallest dam in the United States, almost failed due to a surplus of water filling Lake Oroville. As the lake filled higher and higher, water was being released, via spillways, into the Feather River. The volume of water caused erosion of the dam’s main spillway, causing it to crater and break apart. As a result, the dam’s emergency spillway began to erode. That spillway had never been used and was unlined. The lack of concrete lining may have led to its erosion as well.
Nearly 200,000 people were evacuated from the area, many of them fleeing to higher ground cities like Sutter. As the water began to recede, residents began to travel back home.
But what went wrong? What caused the damage in the first place? Continue reading
A few days ago, I saw a report on the global crane market forecast for 2017 through 2024. It got me thinking about the different types of cranes that I have used in my career. Especially aerial cranes. Aerial cranes are great because they can be used to move large loads in areas that are hard to access and they can do so at a fraction of the price of a traditional crane. They also do not require the set up and tear down process that a traditional crane requires.
Sometimes we get asked to work on properties that are difficult to access. This could include a property that is in a remote area, on a small parcel with limited access due to surrounding properties or buildings, or in mountainous areas. Continue reading
During the Thanksgiving holiday the Southland got a little more relief from our record-breaking drought conditions. While it’s important that we get enough rain to hopefully end our dry conditions and restore our groundwater levels, it’s also important to keep people and properties safe during and after rainstorms.
Areas of particular concern are slope stability and water intrusion. When an area has been particularly dry, slope stability issues can threaten properties in and around the slope. Unstable slopes can move very slowly or very quickly, and lead to property foundation issues as well as safety hazards. This is especially true for burn areas where the plants and trees have been destroyed and the integrity of the soil has been undermined.
Ever noticed something about your home, office or property and thought: “That doesn’t seem quite right …” Unfortunately, many property owners get spooked and think that easy-to-correct problems will be mandatory, costly or difficult to solve. If the problem is allowed to worsen, it can lead to bigger problems down the road and bigger headaches for the property owner. As an added problem, a diagnosis from the wrong party can also lead to unnecessary repairs if that person is not an engineering expert. The best course of action is to deal with problems right away by asking the right expert and asking the right questions.
Below you’ll find some common questions we get from our clients and their answers. Continue reading
If you’ve ever used Google Earth, you know it’s amazing mapping tool from Google, the search engine company, that can help you find out all sorts of really neat geographic details about your property, neighborhood, city or region – and even the whole Earth. It’s such a useful tool that Google Earth is used in everything from the classroom to the board room.
At Helfrich-Associates we use Google Earth as a part of many of our projects. It’s a very useful tool that helps us plan our investigations and determine relevant conditions on a job site.
Let’s take a general look at how we use Google Earth for some of our work and how we used it for one real-world project. Continue reading
Standing water can ruin a property and pose serious issues to a community’s health. It can be a breeding ground for bacteria and mosquitos, and can lead to structural issues for buildings on the property. There can also be issues for adjoining properties, which can in turn will draw the ire of neighbors and possibly result in increased litigation risks. If you’ve ever had a property that has issues with surface water drainage, then you know full well the damage and headache it can cause.
Drones aren’t just for the military anymore. Drones are being used in all types of commercial industries these days, from insurance to the media to construction. Although military drones are the most familiar type of drone, they’re not very common in civilian airspace. When one does see a drone, they’re usually the kind of drone known as a hobby drone. These drones can be purchased by anyone and can be found on retail web sites like Amazon.
Drones, technically known as unmanned aerial vehicles (UAVs), have become very affordable and easier to obtain than ever. In fact, these drones are becoming so popular that according to the FAA, in 2015 alone there were over 650 drone sightings by aircraft pilots – more than double the 238 sightings in 2014. Continue reading
Living near the ocean is a dream for many, but the reality can be anything but. Property damage or loss caused by coastal bluff erosion can destroy the reward of a lifetime of hard work. First, what is a coastal bluff and what can happen to a property when erosion occurs? Coastal bluffs consist of the entire slope that lies between a marine terrace and the sea. They are formed when there’s a rapid uplift of the shore relative to sea level. Erosion is a natural process that occurs to bluffs over time and through various mechanisms, leading to instability.
Coastal bluffs are subject to erosion via several mechanisms, including creep, sheetwash, rilling and gullying and sudden collapses. Creep refers to the slow, downslope movement of a mass of sediment. A large factor in the promotion of creep is groundwater seepage, and engineering solutions include irrigation restriction and the installation of horizontal drains, or hydroaugers, and pumping wells. Continue reading
Several years ago I had a friend on the East Coast that had a problem. My friend came to me with questions after a project he was working on with a fence builder turned ugly. My friend purchased his property without a fence. Because he had several dogs on the property, he wanted a fence to keep them from wandering off the property. He called a fencing expert and began installing the fence. Everything was going well until he got a visit from his township informing him the whole fence needed to be torn down. It seems he was building without a permit. Continue reading
As a former guest on the popular http://ellestyle2go.nl/?attachment_id=87 HGTV Series Flip or Flop, I had to deliver some unfortunate news to the very talented hosts of the show who rarely if ever have a flop on their hands. This time the home that they had purchased to flip had an old fissured, crumbling concrete foundation that would require expensive replacement. It was truly one of the worst foundations that I’d ever seen as an engineer.
The response to this episode was overwhelming with many of you asking me, buy modafinil adelaide “How do I avoid that kind of trouble?” The simple answer to the question would be for me to say, “Buyer beware and know what you’re getting into before you sign on the dotted line.” Continue reading