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Rivers at risk: Read about your city’s water pollution concerns

Rivers at risk: Read about your city’s water pollution concerns
This map shows the state's top 20 cities and the rivers and creeks affected by their wastewater treatment. The thicker the river, the more gallons of treated waste it takes in each day. (Graphic: Matt Jensen Marketing)

Every day, South Dakota’s 20 most populous cities dump 49.2 million gallons of treated human and industrial wastewater into state rivers and creeks. Here is a look at those 20 cities and how they process wastewater, what it costs, recent inspection results, and how much is dumped where.

Sioux Falls Water Reclamation Facility

Location, population served: 4500 N. Sycamore Ave., 178,500 people

Discharge waterway, amount: Big Sioux River, 18.2 million gallons per day

Permit approval/expiration date: Approved July 1, 2000; expired June 30, 2005

System age, status: Built 1985, ongoing consistent upgrades. Fiscal 2016 expenses $22.5 million, revenues $28.5 million; mechanical treatment system.

Industrial wastes accepted: 14 significant industrial users, 320 other industrial users. Major users include Avera McKennan, Sanford and Veteran’s Affairs hospitals, Dean Foods, North End Truck Wash, S.D. Penitentiary, Gage Brothers Concrete. Produce 3.5 percent of overall system inflow.

Inspection date, data: Last on-site inspection September, 2017. Violations: exceeded fecal coliform, exceeded daily pH level, oil and grease levels not properly reported. Sewage leaks (17) include July, 2016 release of 20,000 gallons of grease by hospital that reached state waters, March 2017 release of 302,000 gallons of wastewater from manhole, undetected for a week, reached state waters.

Other permits in city: Seven other discharge permits, including Smithfield Foods (formerly John Morrell) plant, USGS Eros Data Center, L.G. Everist, Northern States Power Anson Plant, and 18/29 Commerce Park.

Notes: City has pre-treatment system for industrial wastes. System accepts untreated wastewater from city of Brandon (650,000 gallons per day), Harrisburg (183,000 gallons per day) and occasionally from Smithfield Foods pork plant (up to 1 million gallons per day during heavy rain events.) Mayor’s long-range capital plan proposes $260 million in wastewater system upgrades, including $160 million alone for the treatment plant which would expand peak capacity from 21 million gallons per day to 30 million gallons per day.

Rapid City Water Reclamation Facility

Location, population served: On Southside Drive, south of state Highway 44 west of Radar Hill Road; 79,900 people

Discharge waterway, amount: Rapid Creek, 12.2 million gallons per day

Permit approval/expiration date: Approved Jan. 1, 2017, expires June 30, 2022

System age, status: Built in 1967, upgrades in 1984, 1991, 2004, 2012 and 2015. Fiscal 2015 expenses $12.6 million, revenues $11.4 million; mechanical treatment system.

Industrial wastes accepted: 14 minor industrial users, 16 other users. Produce 2 percent overall system inflow.

Inspection date, data: Last on-site inspection April, 2016. Violations: two fecal coliform violations, one E.coli violation, two dissolved oxygen violations, failure to sample for whole effluent toxicity once and oil and grease once. Leaks (16) included 1,000 gallons wastewater leaking from basement in April, 2017; manhole overflow led to discharge of 10,000 gallons wastewater in June, 2017.

Other permits in city: Eight other discharge permits, including Black Hills Corp., Pete Lien & Sons, Rapid City Landfill and Weston Heights Sanitation District.

Notes: City has pre-treatment system for industrial wastes. System also accepts untreated wastewater from municipalities of Black Hawk, Northdale, Rapid Canyon, Rapid Valley and Terra Cotta. City’s 20-year facilities plan proposes $62 million in system upgrades.

Aberdeen Water Reclamation Facility

Location, population served: 700 135th St. E.; 28,415 people

Discharge waterway, amount: Moccasin Creek, 2.9 million gallons per day

Permit approval/expiration date: Approved April 1, 2013; expired March 31, 2008.

System age, status: Built in 1987, upgrades in 2006 and 2009. Fiscal 2016 expenses: $4.1 million, revenues $6 million; mechanical treatment system.

Industrial wastes accepted: Six significant industrial users, including Burlington Northern Santa Fe, Advanced Bioenergy, Twin City Fan, Ray-Mac, New Angus LLC and Northwestern Energy. Produce 10 percent overall system inflow.

Inspection date, data: Last on-site inspection April, 2016. Recent violations: entire wastewater collection system under review by state; oil and grease samples not recorded. Leak in August, 2014 left 60 homes with sewer backups, not reported to state as required.

Other permits in city: Five other discharge permits, among them American Biosolids, Country Village and Prairiewood and Richmond Lake sanitary districts.

Notes: City has pre-treatment program for industrial wastes. Proposed or completed upgrades include redoing collection system pipes and lift stations as well as improvements inside treatment plant such as coatings, pumps and gates. New Angus LLC, a beef processing plant formerly known as Northern Beef Packers, sought to increase inflow to Aberdeen treatment facility from 500,000 gallons per day to 1 million gallons per day, but request was rejected due to consistent effluent violations by New Angus. City took enforcement action against New Angus for significant effluent violations in first three months of 2016.

Brookings Municipal Utilities

Location, population served: Two miles south of city on 470th Avenue, 36,484 people (includes SDSU)

Discharge waterway, amount: Big Sioux River, 3.58 million gallons per day

Permit approval/expiration date: Approved on Oct. 1, 2008, expired Sept. 30, 2013

System age, status: Built in 1980, upgrades in 2010, 2012 with major upgrade in 2017. Fiscal 2015 expenses: $3.5 million, revenues $4.8 million; mechanical treatment system.

Industrial wastes accepted: Seven significant industrial users, among them Bel Brands, 3M, Counterpart, Sterling Technologies, Star Circuits and Twin City Fan. Produce 14 percent overall system inflow.

Inspection date, data: Last on-site inspection June, 2018. Recent violations include ammonia limits exceeded August, 2015, failure to report sewage leaks by letter.

Other permits in city: Three other discharge permits, including Dacotah Bank and SDSU.

Notes: City has pre-treatment program for industrial wastes. Excessive hydrogen sulfide gas release by Bel Brands cheese plant in September and October of 2014 created potential for manhole explosion and put Brookings employees at risk. Bel Brands had 78 violations issued by city in 2014 and paid $41,000 in fines. Recent system upgrades include UV disinfection process, new clarifiers and new filters. Two miles of sewer lines redone every year.

Watertown Wastewater Treatment Facility

Location, population served: 1300 11th St., SE; 22,172 people

Discharge waterway, amount: Big Sioux River, 2.83 million gallons per day

Permit approval/expiration date: Approved July 1, 2014; expired June 30, 2009

System age, status: Built in 1997, upgraded headworks in 2011. Fiscal 2014 expenses $2.89 million, revenues $3.55 million; mechanical treatment system.

Industrial wastes accepted: 14 significant industrial users, including Dakota Tube, Glacial Lakes Energy, Miller Electrical Manufacturing, Metrix, Persona and Worthington Industries. Produce 3 percent total system inflow.

Inspection date, data: Last on-site inspection May, 2015; no recent violations reported. Minor sewage backups reported in 2014 and 2015.

Other permits in city: Two other discharge permits for Glacial Lakes Energy and Sioux River Dairy.

Notes: City has pre-treatment facility for industrial waste. City recently converted to UV disinfection process. State inspectors praise city employees, calling system an “excellent operation.” Sioux River Dairy is a concentrated animal feeding operation with 1,025 head of cattle.

Mitchell Wastewater Treatment Facility

Location, population served: 2141 E. Havens St., 15,254 people

Discharge waterway, amount: James River, intermittent discharge, 819.6 million gallons discharged in 2015, average of 2.2 million gallons per day. System designed to process 2.3 million gallons per day.

Permit approval/expiration date: Approved Oct. 1, 2012; expired Sept. 30, 2017

System age, status: Built 1976, upgraded in 1997, 2006-07. Fiscal 2017 expenses $2.07 million, revenues $2.08 million; hybrid system with mechanical treatment and stabilization ponds.

Industrial wastes accepted: Four significant industrial users, including Performance Pets, Quality Woods, Trail King Industries and Twin City Fan. Produce 8 percent total system inflow.

Inspection date, data: Last on-site inspection September, 2017. Recent violations: pH exceeded in June 2016, leak discovered in land application line, industrial users not properly tested for all parameters, recent oil and grease violations by Performance Pets.

Other permits in city: Three other discharge permits for Poet Biorefining, Rosedale Hutterian Brethern and Scott Supply Co.

Notes: City has pre-treatment program for industrial wastes. One-fourth city sewer lines jet-cleaned each year, new storm sewer was in budget for 2017.

Yankton Wastewater Treatment Facility

Location, population served: 700 Levee St., 14,566 people

Discharge waterway, amount: Missouri River, 1.7 million gallons per day

Permit approval/expiration date: Approved Oct. 1, 2015; expires Sept. 30, 2020

System age, status: Built 1964, upgraded in 1976, 1980, 2003 and 2011. Fiscal 2013 expenses $2.93 million, revenues $2.94 million; mechanical treatment system.

Industrial wastes accepted: One significant industrial user (CIMPL beef processor), six other industrial users: Applied Engineering, Alcoa Aluminum, Freeman Company, Gehl Power Products, Lewis and Clark Hydraulic, M-Tron Industries and American Foods Group. Produce 20 percent overall system inflow (CIMPL accounts for 13 percent.)

Inspection date, data: Last on-site inspection June, 2015. Recent violations include recording and reporting errors in 2015, a fecal coliform violation in 2013.

Other permits in city: Twelve other discharge permits for, among others, CIMPL, Hydro Extrusions, Manitou Americas and Lewis & Clark Hydraulics.

Notes: Lift stations redone recently, one-third sewer lines cleaned annually. CIMPL wastes subject to industrial pre-treatment program.

Pierre Wastewater Treatment Facility

Location, population served: 1103 S. Buchanan St., 14,008 people

Discharge waterway, amount: Lake Sharpe (Missouri River), 1.7 million gallons per day

Permit approval/expiration date: Approved Oct. 1, 2015, expires Sept. 30, 2020.

System age, status: Built 1962, upgraded in 1999, 2000, 2003 and 2016. Fiscal 2015 expenses $3.94 million, revenues $4.40 million; mechanical treatment system.

Industrial wastes accepted: No significant industrial users.

Inspection date, data: Last on-site inspection May, 2016. Recent violations: Total of 17 effluent violations from September 2015 to March 2016 for fecal coliform, total coliform, pH and residual chlorine (13). Four invalid biological demand tests 2015-16; “Excessive” violations noted in 2015 inspection with 44 effluent violations noted for exceedance of fecal coliform (23), total residual chlorine (13), multiple invalid tests. Lack of emergency procedures on file. Overflows and bypasses not sampled or reported properly to state. Leakage during September 2016 sewer line bypass discharged 50 gallons raw sewage on Capital Street. Airport lift station leaked 50 gallons of sewage in January 2015.

Other permits in city: 3 other discharge permits for Pierre Regional Landfill, Spring Creek Sanitary District and U.S. Army Corps of Engineers Oahe Dam.

Notes: City planned major system overhaul and upgrade for 2016; status not reported in files.

Huron Wastewater Treatment Facility

Location, population served: 1280 Ninth St. S.E., 13,117 people.

Discharge waterway, amount: James River and mitigated wetlands, intermittent discharge, 10.48 million gallons discharged to wetland in 2015, average of 29,000 gallons per day. System designed to process 2.3 million gallons per day.

Permit approval/expiration date: Approved April 1, 2013, expired March 31, 2018.

System age, status: Built 1968, upgraded in 1991, 1996, 2008 and 2010. Fiscal 2014 expenses $1.81 million, revenues $2.21 million; hybrid system with mechanical treatment and stabilization ponds.

Industrial wastes accepted: Six significant industrial users, including DaPro Rendering, Dakota Provisions, Advanced Bioenergy, HMI, Truss Built and Protective Coating Specialists. Produce 31 percent overall system inflow.

Inspection date, data: Last on-site inspection November, 2015. City has had consistent issues with violations by industrial users of the system, including Dakota Provisions turkey processing plant and DaPro, its dog food offshoot. In 1997, the U.S. Environmental Protection Agency declared Huron in Significant Noncompliance for chronic effluent violations. The city has not updated its local pollution limits since 1993. In 2015 inspection of the city industrial pre-treatment system, Dakota Provisions had 27 oil and grease exceedances over the past 15 months and DaPro had five. City also did not meet sampling frequency requirement for oil and grease from industrial users. Dakota Provision permit does not contain sampling requirements for several pollutants.

Other permits in city: One other discharge permit for Huron Water Treatment Plant.

Notes: City has industrial waste pre-treatment program. City drinking water treatment plant discharged 3.27 million gallons of wastewater to an unnamed tributary of Stoney Run Creek in 2015. City undergoing sewer line upgrades and manhole rehabs through 2020. Future upgrades planned and updates to local pollution limits being considered.

Spearfish Water Treatment Facility

Location, population served: U.S. 85, two miles north of city; 11,531 people

Discharge waterway, amount: Spring Creek to Redwater River, 1.1 million gallons per day

Permit approval/expiration date: Approved April 1, 2005, expired March 31, 2010.

System age, status: Built 1982, upgraded in 1993, 2009 and 2015. Fiscal 2016 expenses $2.37 million, revenues $2.87 million; mechanical treatment system.

Industrial wastes accepted: No significant industrial users (Crow Peak Brewery contributes small inflow to system.)

Inspection date, data: Last on-site inspection May, 2017. Recent violations: Total suspended solids violation in October, 2014. Minor system leaks in October 2015 due to rags from Holiday Inn and in May 2016 due to blockage by grease buildup from Walmart.

Other permits in city: Three other discharge permits for McNenny Fish Hatchery, Spearfish Forest Products and state Interstate 90 rest area.

Notes: City also processes wastewater for Black Hills State University and Spearfish Valley Sanitation District. New concrete biosolids drying pad constructed in 2015; upgrades to valves and main lift station planned.

Vermillion Wastewater Treatment Facility

Location, population served: 1530 South Dakota St., 10,844 people.

Discharge waterway, amount: Vermillion River to Missouri River, 1.1 million gallons per day

Permit approval/expiration date: Approved Oct. 1, 2012, expired Sept. 30, 2017.

System age, status: Built in 1966, upgraded in 1986, 1997, 2005, 2009, 2010-11. Fiscal 2016 expenses $1.58 million, revenues $1.92 million; mechanical treatment system.

Industrial wastes accepted: No significant industrial users.

Inspection date, data: Last on-site inspection April, 2017. Inconsistent data reporting noted. System leaks include manhole overflow into meadow in June, 2015 and from frozen sewer line in November, 2015.

Other permits in city: One other discharge permit for highway rest area.

Notes: City also processes wastewater for 7,000 people at University of South Dakota. Recent planned upgrades include rebuilding lift station and replacement of some sewer lines. System received Operation and Maintenance Award from state in 2008, 2009, 2010, 2012 and 2015.

Brandon Wastewater Treatment Facility

Location, population served: Northwest of city on Redwood and Sioux boulevards, 9,923 people

Discharge waterway, amount: Wastewater discharged to city of Sioux Falls, then to Big Sioux River, 650,000 to 700,000 gallons per day

Permit approval/expiration date: Approved April 1, 2000, expired March 31, 2005

System age, status: Built 1982, upgraded 1991 and 2002. Fiscal 2014 expenses $942,000, revenues $1.12 million; no wastewater treatment on site,

Industrial wastes accepted: No significant industrial users.

Inspection date, data: Last on-site inspection August, 2014. Recent violations include two biological oxygen demand exceedances in July, 2014 and two ammonia violations in June, 2014. Previous violations include ammonia and fecal coliform exceedances in May, 2014, fecal coliform violation in May, 2014, and biological oxygen demand violations in July and October, 2013. Sinkhole formed due to water main break in May, 2015.

Other permits in city: Two other discharge permits for Marmen Energy and Midwest Rail Car Repair.

Notes: City recently built new $2.6 million lift station for discharge of untreated sewage in a 2.5-mile pipe to Sioux Falls treatment plant. No discharge to Big Sioux River since June, 2017; discharges to Sioux Falls except in emergencies when wastes can be stored in holding cell for up to 30 days. About 27 miles of sewer lines cleaned in past three years.

Box Elder, operated by S.D. Ellsworth Development Authority

Location, population served: 1581 Highway 14/16, serves 17,800 people (7,800 in Box Elder, 9,000 at Ellsworth Air Force Base)

Discharge waterway, amount: Unnamed tributary of Box Elder Creek, 1.1 million gallons per day

Permit approval/expiration date: Approved April 1, 2014, expires March 31, 2019

System age, status: Built in 2014. Treatment facility privately run by Project Solutions, Inc. of Rapid City. No budget information provided; mechanical treatment system.

Industrial wastes accepted: No significant industrial users

Inspection date, data: Last on-site inspection August, 2017. Failure of whole effluent testing four months in 2016 and three months in 2017 due to levels of toxicity testing microbe ceriodaphnia dubia; state instituted toxicity identification and reduction evaluation to find source of problems. Ammonia effluent violation in November, 2014 and biological dissolved oxygen violation in September, 2014. Some sampling and reporting errors in 2014-15.

Other permits in city: No other local discharge permits.

Notes: Ellsworth Air Force Base has oil/water separation pre-treatment process for base wastes.

Madison Wastewater Treatment Facility

Location, population served: Intersection of state Highway 34 and County Road 38, serves 7,425 people

Discharge waterway, amount: Permit does not allow direct waterway discharge; treated wastes flow to Park/Silver Creek to Bourne Slough to Lake Madison, system processes 709,500 gallons per day

Permit approval/expiration date: Approved July 1, 2017, expires June 30, 2022

System age, status: Built 1984, upgraded in 2009. Fiscal 2017 expenses $1.42 million, revenues $1.68 million; mechanical treatment system.

Industrial wastes accepted: Two significant industrial users, Gehl/Manitou Americas and Persona, Inc. Produce 15 percent overall system inflow. Minor industrial contributors include Global Polymer and Integra.

Inspection date, data: Last on-site inspection June, 2018. Recent violations: Improper collection and sampling after sewage backup in January, 2018. No backup power source for lift station.

Other permits in city: Four other discharge permits for Lake Madison Sanitary District, Manitou Americas, Persona, Inc. and state game and fish department.

Notes: State inspector in 2015 commended facility and employees for “excellent records, operation, maintenance, and preventive maintenance programs.”

Sturgis Wastewater Treatment Facility

Location, population served: 4800 Harley-Davidson Way, 9,333 people

Discharge waterway, amount: Permit does not allow direct waterway discharge; treated wastes flow to Bear Butte Creek, system processes 1 million gallons per day.

Permit approval/expiration date: Approved April 1, 2007, expired March 31, 2012

System age, status: Built 1963, upgraded 1992; building new mechanical system 2018-20. Fiscal 2018 expenses $945,000, revenues $2.01 million; hybrid system with mechanical treatment and stabilization ponds.

Industrial wastes accepted: Two significant industrial users, Dakota Arms and Fort Meade Veterans Affairs Hospital. Produce 10 to 30 percent of total system inflow.

Inspection date, data: Last on-site inspection June, 2018. System reported to be near or at functioning capacity, with emergency discharges now possible during heavy storms or Sturgis motorcycle rally. System had four emergency discharges in 2010.

Other permits in city: Two other water discharge permits in city for Dakota Arms and town of Buffalo Chip.

Notes: System designed for population of 7,000. Half of sewer lines cleaned each year. Permit allows land application of wastewater to area farms and groves. Town of Buffalo Chip hosts 10,000 people for 10-day annual rally and processes 670,000 gallons of wastewater during that time.

Harrisburg Wastewater Treatment Facility

Location, population served: 203 S. Prairie St, 5,734 people

Discharge waterway, amount: Permit does not allow direct waterway discharge; since 2010, excess wastewater sent to Sioux Falls system (33 million gallons during first six months of 2015, average of 183,300 gallons per day.)

Permit approval/expiration date: Approved Oct. 1, 2016, expires Sept. 30, 2021

System age, status: Built 1999, upgraded in 2008 and 2010. Fiscal 2014 expenses $666,400, revenues $760,400; stabilization pond system with three holding cells.

Industrial wastes accepted: No significant industrial users

Inspection date, data: Last on-site inspection June, 2015; no recent violations. In May, 2013 heavy rains caused system overflow into storm sewers.

Other permits in city: No other local discharge permits.

Notes: City installing new pipes between settling ponds, relining some manholes.

Belle Fourche Wastewater Treatment Facility

Location, population served: 1.5 miles north of city, 5,655 people

Discharge waterway, amount: Permit does not allow direct waterway discharge; treated wastes flow to unnamed tributary of Crow Creek to Belle Fourche Reservoir; system processes 450,000 gallons per day

Permit approval/expiration date: Approved Nov. 1, 2017, expires Oct. 30, 2022

System age, status: Built 1959, upgraded in 1982 and 1990. Fiscal 2014 expenses $463,250, revenues $423,850; stabilization pond system with four holding cells and 13 wetlands.

Industrial wastes accepted: 13 non-significant industrial users, including Integrity Meats, Pipeline Plastics, Permian Tanks, Dakota Mill & Grain and Superior Truss Systems

Inspection date, data: Last on-site inspection August, 2015. No recent violations. Clogged sewer line under Seventh Avenue led to wastewater spill in March, 2016. Emergency discharge February through March, 2015 led to release of 118 million gallons.

Other permits in city: No other local discharge permits.

Notes: Entire system jet-cleaned each year. Plans in place to replace lift stations and add another discharge wetland.

Tea Wastewater Treatment Facility

Location, population served: 600 E. First St., 5,032 people

Discharge waterway, amount: Nine Mile Creek, intermittent discharging, 10 discharges in 2014-15. Two discharges in 2017 totaled 44.8 million gallons, average of 125,000 gallons per day. System processes average of 295,000 gallons of wastewater per day.

Permit approval/expiration date: Approved Jan. 1, 2016, expires Dec. 31, 2020

System age, status: Built in 1968, upgraded 1988, 1999 and 2003. Fiscal 2016 expenses $344,200, revenues $454,100; stabilization pond treatment system with four holding cells.

Industrial wastes accepted: No significant industrial users.

Inspection date, data: Last on-site inspection June, 2017. Recent violations include failure to sample for ammonia in April, 2016; since 2010, five total suspended solids violations and one pH violation.

Other permits in city: No other local discharge permits.

Notes: Plans in place to begin sending sewage to Sioux Falls system for treatment in next few years.

Dell Rapids Wastewater Treatment Facility

Location, population served: Quarry Road and 474th Avenue, 3,705 people

Discharge waterway, amount: Big Sioux River, intermittent discharge, average of twice per year. December, 2015 discharge totaled 6.34 million gallons, average of 34,500 gallons per day. System processes average of 220,000 gallons per day.

Permit approval/expiration date: Approved Nov. 1, 2014, expires Sept. 30, 2019

System age, status: Built 1975, upgraded in 2001. Fiscal 2016 expenses $1.3 million, revenues $1.3 million; hybrid system with mechanical treatment, stabilization ponds and land application.

Industrial wastes accepted: Four non-significant industrial users; Dell Rapids Custom Trailers, Dells Materials, L.G. Everist, Troy’s Wood Specialties.

Inspection date, data: Last on-site inspection June, 2016. Recent violations include seven late reports 2014-15, ammonia violation May, 2015, unknown and unmonitored discharge in June, 2016. Some backups into homes reported in recent years. City is under sate construction compliance schedule to upgrade facility in order to accommodate growing population.

Other permits in city: No other local discharge permits.

Notes: Recent upgrade to sequencing batch reactor, some sewer lines replaced. One-third of sewer system cleaned annually. City allowed to apply treated wastewater to local municipal golf course.

Mobridge Wastewater Treatment Facility

Location, population served: 1401 Lake Front Drive, 3,570 people

Discharge waterway, amount: Lake Oahe (Missouri River), 350,000 gallons per day.

Permit approval/expiration date: Approved July 1, 2011, expired June 30, 2016

System age, status: Built 1958, upgraded 1976, 1990, 1998, 2005 and 2016. Fiscal 2014 expenses $462,000, revenues $486,000; mechanical treatment system.

Industrial wastes accepted: 11 non-significant industrial users, including West Side Meats, Mobridge Regional Hospital, Golden Living Center, Bridge City Publishing and Fabra-Tech Laundry.

Inspection date, data: Last on-site inspection September, 2017. Recent violations include E. coli exceedance August, 2017, two total coliform violations in September, 2015 and March, 2017. May, 2017 discharge report not filed. Lift station overflowing during inspection, alarm not functioning.

Other permits in city: No other local discharge permits.

Notes: Second clarifier added in 2017; recent upgrade to UV disinfection.


Notes: Discharge amounts are continuous on a daily basis unless otherwise noted; most population figures are from 2016 census; and information comes mainly from state surface water discharge permit documents. Most treatment plants must test for and remain within allowable limits of ammonia, biological oxygen demand, dissolved oxygen, nitrates, oil and grease, pH, total suspended solids and wastewater discharge temperature.