The big hole in the ground at 4th and Main is the underground garage and basement for the new Merrill Gardens project that is coming in 2023. Downtown will never look the same after this 7-story modern palace rises up. Bringing much-needed housing to downtown, the project is in the toughest phase it faces for sure. One question has been on everyone’s mind as they drive by. What the heck is all that water from?
To answer that question the Herald staff has visited with site contractors and City staff on several occasions. The bottom line is that groundwater began to fill the massive hole shortly after digging started, and that is not uncommon on projects like this. At over 15 feet deep the hole is the deepest of its kind that we can find any record of anyone digging in recent years. Most locals know that water can be found about 5 feet down in the winter and a little deeper in Summer. We are after all in an old lake bed here on the valley floor. Well, the water the developers hit was enough to where it has to be pumped 24 hours a day into a large container, like a truck trailer. It fills that trailer which has filters in it and once the water is filtered it is dumped into our storm drains. This is called dewatering.
Dewatering can be dangerous and is something that must follow steps and be monitored. No doubt that Slean Water services and the City of Hillsboro had staff watching over this one. But once the water started flowing it has not stopped. And it has been at least 6 months. Explained by contractor Perlo, here is what they say:
Dewatering is the process of removing surface or groundwater from a particular location. Most construction work cannot occur in areas with significant water ponding, so techniques have been designed to move water out of each area for the duration of construction. The process typically involves sloping the areas of work to drain water away, pumping surface water to another location, or drilling a series of well-points into the ground around the area of work and pumping it to another location in order to artificially lower the water table while work is occurring.
Find out more here: https://perlo.biz/construction-dewatering-what-is-it-and-why-does-it-matter/
The question is will this lengthy and very expensive process be repeated by future developers in the area? Should we consider local wells and the health of the aquifer? Whatever happens this has been quite something to watch and that is a LOT of water! We will keep an eye on this project as it head skyward and up and out of the water!