Metro Wastewater Reclamation District Research Articles

Inducing granulation within a full-scale activated sludge system to improve settling.

Most cold-climate biological nutrient removal facilities experience poor settling mixed liquor during winter, resulting in treatment capacity throughput limitations. The Metro Wastewater Reclamation District in Denver, Colorado, operated two full-scale secondary treatment trains to compare the existing biological nutrient removal configuration (Control) to one that was modified to operate with an anaerobic selector and with hydrocyclone selective wasting (Test) to induce granulation. Results from this evaluation showed that the Test achieved significantly better settling behaviour than the Control. The difference in the mean diluted SVI30 between the Test and Control were statistically significant (P < 0.05), with values of 77 ± 17 and 135 ± 25 mL/g observed for the Test and Control respectively. These settling results were accompanied by differences in the particle size distribution, with notably higher settling velocities commensurate with increasing particle size. The degree of granulation observed in the Test train was between 32 and 56% of the mass greater than ≥250 μm in particle size whereas 16% of the mixed liquor in the Control was ≥250 μm over the entire study period. The improved settling behaviour of the Test configuration may translate into an increase of secondary treatment capacity during winter by 32%.

Ready for Today—and Tomorrow

The Metro Wastewater Reclamation District’s new 24 mgd Northern Treatment Plant, near Denver, represents one of the most advanced facilities of its kind in the western United States. Delivered by means of the progressive design/build method, the facility is designed to meet stringent existing regulatory requirements as well as stricter standards anticipated in the future.

Ten Year Performance Study for Air Ionized Odor Control at the Denver Metro Wastewater Reclamation District

Ten Year Performance Study for Air Ionized Odor Control at the Denver Metro Wastewater Reclamation District

Long-Term Monitoring Results for the METROGROFarm Near Deer Trail, Colorado

Long-Term Monitoring Results for the METROGROFarm Near Deer Trail, ColoradoFollowing opposition to the land application of biosolids on the METROGRO farm, near Deer Trail, CO, the Metro Wastewater Reclamation District contracted with the United States Geological Service to conduct monitoring at the METROGRO farm. Studies of dust conducted over a two year period and studies of crops conducted over a ten year period indicated no detrimental effects from the land...Author(s)James JohnsonArlisa MichaelAlicia GilleySourceProceedings of the Water Environment FederationDocument typeConference PaperPublisherWater Environment FederationPrint publication date May, 2013ISSN1938-6478DOI10.2175/193864713813536723Volume / Issue2013 / 5Content sourceResiduals and Biosolids ConferenceCopyright2013Word count74

Sustainable Return on Investment –Metro Wastewater Reclamation District's Application of Nutrient Criteria Cost Benefit Alternative Analyses

Sustainable Return on Investment –Metro Wastewater Reclamation District's Application of Nutrient Criteria Cost Benefit Alternative Analyses

Effective Strategic Planning at Metro Wastewater Reclamation District (MWRD) – It's All About Alignment and Execution

Effective Strategic Planning at Metro Wastewater Reclamation District (MWRD) – It's All About Alignment and Execution

In with the New A Look at the Metro Wastewater Reclamation District's (MWRD) GIS Biosolids Land Application Operation

In with the New A Look at the Metro Wastewater Reclamation District's (MWRD) GIS Biosolids Land Application OperationThe Metro Wastewater Reclamation District (District) in Denver, Colorado is the largest wastewater treatment facility between the Mississippi river and the west coast. The District treats approximately 130 million gallons of wastewater and produces an average of 80 dry tons of Class B biosolids per day. On an annual average basis, 88 percent of the biosolids are transported from the Robert W. Hite...Author(s)Arlisa L. MichaelSourceProceedings of the Water Environment FederationSubjectSession 17 - Land ApplicationDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2009ISSN1938-6478SICI1938-6478(20090101)2009:3L.1112;1-DOI10.2175/193864709793846187Volume / Issue2009 / 3Content sourceResiduals and Biosolids ConferenceFirst / last page(s)1112 - 1117Copyright2009Word count275Subject keywordsGISFarm WorksBiosolids

THE EMS FOR BIOSOLIDS PUZZLE: HOW THE METRO WASTEWATER RECLAMATION DISTRICT SUCCESSFULLY PUT THE PIECES TOGETHER

THE EMS FOR BIOSOLIDS PUZZLE: HOW THE METRO WASTEWATER RECLAMATION DISTRICT SUCCESSFULLY PUT THE PIECES TOGETHERThe Metro Wastewater Reclamation District (District) provides wastewater treatment for about 1.5 million people in the Denver metro area. The District treats about 140 million gallons of wastewater and produces about 75 dry tons of biosolids per day. The District has been committed to the beneficial reuse of biosolids since 1978, when the Board of Directors adopted a resolution which, in part,...Author(s)A. MitchellP.E. Costanzo,Foster AngelSourceProceedings of the Water Environment FederationSubjectSession 6: Environmental Management SystemsDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2006ISSN1938-6478SICI1938-6478(20060101)2006:2L.262;1-DOI10.2175/193864706783797267Volume / Issue2006 / 2Content sourceResiduals and Biosolids ConferenceFirst / last page(s)262 - 269Copyright2006Word count477

Plant and soil responses to biosolids application following forest fire.

Soil stability and revegetation is a great concern following forest wildfires. Biosolids application might enhance revegetation efforts and enhance soil stability. In May 1997, we applied Metro Wastewater Reclamation District (Denver, CO, USA) composted biosolids at rates of 0, 5, 10, 20, 40, and 80 Mg ha(-1) to a severely burned, previously forested site near Buffalo Creek, CO to improve soil C and N levels and help establish eight native, seeded grasses. The soils on the site belong to the Sphinx series (sandy-skeletal, mixed, frigid, shallow Typic Ustorthents). Vegetation and soils data were collected for four years following treatment. During the four years following treatment, total plant biomass ranged from approximately 50 to 230 g m(-2) and generally increased with increasing biosolids application. The percentage of bare ground ranged from 4 to 58% and generally decreased with increasing biosolids rate. Higher rates of biosolids application were associated with increased concentrations of N, P, and Zn in tissue of the dominant plant species, streambank wheatgrass [Elymus lanceolatus (Scribn. & J.G. Sm) Gould subsp. lanceolatus], relative to the unamended, unfertilized control. At two months following biosolids application (1997), total soil C and N at soil depths of 0 to 7.5, 7.5 to 15, and 15 to 30 cm showed significant (P < 0.05) linear increases (r2 > 0.88) as biosolids rate increased. The surface soil layer also showed this effect one year after application (1998). For Years 2 through 4 (1999-2001) following treatment, soil C and N levels declined but did not show consistent trends. The increase in productivity and cover resulting from the use of biosolids can aid in the rehabilitation of wildfire sites and reduce soil erosion in ecosystems similar to the Buffalo Creek area.

MOVING THE NEEDLE: IT'S WHAT YOU DO, NOT WHAT YOU SAY THAT COUNTS

MOVING THE NEEDLE: IT'S WHAT YOU DO, NOT WHAT YOU SAY THAT COUNTSIn 1993, the Metro Wastewater Reclamation District, the wastewater treatment authority that serves 1.5 million citizens in metropolitan Denver, CO, began buying land in Eastern Colorado near the small agricultural community of Deer Trail, CO, to use as a biosolids land application site. Over the next several years, Metro acquired 52,000 acres of agricultural land that lies in two counties and is...Author(s)Stephan D. FrankLisa A. SiglerSourceProceedings of the Water Environment FederationSubjectSession 4: Building Public Support and Tackling PoliticsDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2004ISSN1938-6478SICI1938-6478(20040101)2004:1L.276;1-DOI10.2175/193864704784343153Volume / Issue2004 / 1Content sourceResiduals and Biosolids ConferenceFirst / last page(s)276 - 285Copyright2004Word count166

Colorado Utility Wins Environmental Award

This article discusses how the Metro Wastewater Reclamation District (MWRD) in Denver, Colorado, received the Environmental Leadership Alliance award from Severn Trent Services. The award program was established by Severn Trent to acknowledge clients who have worked in collaboration with the company to achieve economic savings while also protecting and preserving the environment. MWRD replaced its coagulant‐feeding system with a Semblex(R) automated polymer system from Severn Trent, and the utility is realizing significant economic savings. Increased operational efficiency has resulted in less downtime and reduced maintenance costs. Also, the new system utilizes recycled wastewater effluent, which replaces the use of potable water in the polymer preparation process. The resulting high‐quality biosolids are a soil amendment and fertilizer marketed as METROGRO(TM).

Assessing river habitat selection by waterfowl wintering in the South Platte River, Colorado

We assessed river habitat selection of waterfowl wintering in the South Platte River below the Metro Wastewater Reclamation District treatment plant in Adams County, Colorado to determine potential impacts of proposed river channel modifications. Daily mean number of waterfowl was 711 per km of river over the study area, and 19 species of waterfowl were observed. We describe use of a resource selection model to evaluate whether a habitat type is selected more than expected based on its availability. Habitat selection indices indicated that Canada geese (Branta canadensis) used all habitats in proportion to their availability. Dabbling ducks selected large pools, secondary channels, riffles and sandbars, avoided smaller pools and islands, and used runs in proportion to their availability. Diving ducks selected large pools, small pools, and runs; they avoided secondary channels, riffles, sandbars, and islands. Due to different habitat preferences between diving and dabbling ducks, changes that alter river habitat structure may favor some species and not benefit others. The optimum way to maintain diversity and abundance of waterfowl wintering in the South Platte River is to maintain a variety of habitat types.