Reclamation facility expansion solves Colorado community’s growing pains
A large-scope facility
Most large-scale water facilities projects require extended timelines, and the Parker facility expansion project was first discussed in a 2014 master plan. Preliminary studies and evaluation started in 2016, and design of the facility expansion began in 2017. Construction started in 2019.
“Parker has two water reclamation facilities, so there was a lot of evaluation of whether we were going to consolidate plants, whether we were going to take one offline, and what would we do in expansion of the NWRF,’’ Sansom said. “There was a lot of evaluation, and we were looking at new technologies. It was a lot of collaboration to get through design, but we really wanted to make sure that we were planning for the future and weren’t just duplicating what we had.”
The project included a new headworks facility, the addition of primary clarification, expansion of the advanced water treatment (AWT) equalization, treatment, and pumping capacity, replacement of chlorine disinfection and ultraviolet disinfection, conversion of existing aerobic digesters to autothermal thermophilic aerobic digestion (ATAD), capacity upgrades to the dewatering facilities, and new primary plant power, metering and distribution.
The overwhelming scope of the project was made more challenging by the requirement to maintain plant operations throughout construction.
“You can’t just shut off a wastewater plant,’’ Sansom said. “When you have a community that’s still growing, people are still flushing toilets and using showers. It’s got to go somewhere. We really focused on keeping the existing plant operational and that required careful coordination between the contractor and our operations staff.”
Strict discharge requirements
Parker’s water setup includes multiple facilities and is unusually complex. For starters, not all of Parker’s residents are served by the Parker Water & Sanitation District.
PWSD serves about 20,110 accounts and anticipates serving 35,000 by 2040. It relies on multiple water sources to meet the community’s demand. Its resources include the Water Infrastructure & Supply Efficiency (WISE) partnership, Cherry Creek, Newlin Gulch and the Denver Basin Aquifer. PWSD pulls water from those sources depending on the season, daily water demand and drought conditions.
The Rueter-Hess Reservoir, which was completed in 2012, encompasses 1,170 acres and is a key element in solving Parker’s long-term goal of reaching 75% renewable water supply for the community. The reservoir has a capacity of 75,000 acre feet and is a water resource for PWSD, partner districts, residents of Douglas County and the residents of the Colorado Front Range. The Rueter-Hess Water Purification facility treats up to 10 MGD from the reservoir.
The North and South Water Reclamation Facilities use the highest standards of advanced wastewater treatment to filter, treat and clean water to meet and exceed federal clean water standards. The treated water is discharged into Cherry Creek or is transported to the Rueter-Hess Reservoir.
“We have very strict discharge requirements,’’ Sansom said. “It’s not direct potable reuse. It’s more an indirect potable reuse. We have very low nitrogen and phosphorus requirements that we have to meet.”
Equipment access
Workers need to access equipment at the facility for maintenance and replacement, and Garney installed 10 roof hatches manufactured by BILCO for the reclamation facility.
“We’ve been using BILCO hatches in existing buildings throughout the district,’’ Sansom said. “We haven’t had problems with the bulk of the hatches in the past. So why change something if it’s already working? It makes it easier on operations and maintenance when we’ve got the same equipment throughout the district.”
BILCO hatches are frequently used in projects related to the wastewater management. The hatches are corrosion resistant and feature one-hand operation. Dalco Industries, BILCO’s representative in Colorado, provided the doors for Garney. Two of the hatches are 7-feet-by-12-feet, and the other eight are 5-feet-by-9-feet.
“We’ve found the BILCO hatches work well,’’ Sansom said. “The corrosion resistance is great, and we haven’t had any issues with them on this or in previous projects. As much as we can we like to remain working with the same manufacturer.”
Addressing the future
PWSD realizes Parker is not yet done growing. There is not much time, however, as residents continue to flock to the community just 25 miles southeast of Denver.
“We are about 60% built out, and we anticipate that build out being done by 2040,’’ Sansom said. “That’s not actually that far away in the grand scheme of things. We know because of that growth, we’re always looking ahead to that next big project to make sure we’re delivering adequate water and wastewater services.”
Parker will never go back to the tiny community where people could ride horses anywhere they wanted. PWSD is taking important steps to meet the needs of its soaring population.
“Our vision is sustaining life for our community,’’ Sansom said. “We provide water services and we treat wastewater and that’s the kind of lifeblood that every community has to have. As employees, we’re really motivated by that vision and we work hard to achieve that every day.”