What? The removal of a dam during drought conditions?

What? The removal of a dam during drought conditions? On Thursday morning, July 28, 2022, I went to observe the Hemphill Dam on the Auburn Ravine, just before the construction crews came in to start removing it. What? Remove a dam when we have drought conditions? Yes, absolutely. This is not what you are thinking at all. This dam has been in existence for around 100 years and only exists to raise water levels high enough to allow for the Hemphill Diversion, which provides non-potable, raw water from the Auburn Ravine to the Hemphill Canal. This gravity-fed canal flows water to golf courses such as Turkey Creek and Sun City Lincoln Hills and several other areas such as Lincoln Crossing Community Association before flowing back into the Auburn Ravine downstream by the Thunder Valley Casino. This construction project will still allow plenty of water to be diverted to the canal but it will have a wonderful bonus feature that I'll describe later. Where did the Hemphill name come from? No one knows for sure but those who researched discovered that in the early 1900s, Wallace Hemphill was selling raw water to the city of Roseville. It is believed that he was the builder of this dam and was for whom it is named. Most of the water below this dam is owned by Placer County Water Agency (PCWA). The water that gets diverted into the canal is for the Nevada Irrigation District (NID). Even though all the maps say it's a dam, NID doesn't call this a dam. They call it a water diversion facility, which is really a more accurate term. So why take it down and why are they in a rush to complete it by October? In our area, Chinook salmon typically start the spawning migration in early November and steelhead usually enter local creeks a bit later. This dam removal will be completed in October so as not to disrupt the migration. The Hemphill Dam has the ability for salmon to get over it but only a small percentage are able to do so because it's such a hazardous jump. And even for the 7 percent to 10 percent who make it over the dam, the survival rate of the juveniles coming back downstream over the dam is small because many die from injuries as they fall from the dam's top onto the dangerous sloping face below. Also, some swim into the unscreened canal and it's believed that none survive. Hence the reasons they will rework this configuration. This modification will include a fish screen on the diversion intake area to keep fish from taking that dangerous detour. A multi-agency partnership will use funding from the Wildlife Conservation Board and NID funds to temporarily reroute the stream, ensuring the canal receives flows, remove the dam's cement and steel structure and replace it with a modern, roughened-rock ramp made of boulders and a variety of smaller rocks. This allows for enough water elevation behind the structure so water can still be diverted into the canal. It also makes for a much easier path for all of the salmon to get upstream and enjoy another six miles of spawning territory instead of the measly two miles they currently have from downtown Lincoln to this dam. The construction will be done by Westcon Construction, a local contractor, which helps our local economy too. As I talk to people who live here and are moving here, it is an overwhelming majority of residents who say they love Placer County. That's because there is so much nearby wildlife and open space areas within close proximity to their homes, even when they live in the dense cities of Roseville, Rocklin and Lincoln. It is a blessing to our children and grandchildren that numerous organizations are working hard to help preserve our natural resources. If you'd like to see a video of this dam and location, go to www.TalkToScott.org/hemphill. Scott Alvord, MBA-MCA, BSCS, is an award-winning business owner and CEO of Advanced Development Concepts, LLC. He can be reached at www.ADCBiz.com or 916- 782-4272.