PEÑA BLANCA, NEW MEXICO

PROBLEM 

Outdated, neglected, or nonexistent wastewater systems posed a public health risk to the 800 citizens of Peña Blanca, New Mexico. Open cesspools and seepage pits emptied into yards and irrigation canals. Surveys revealed that 86% of the individual wastewater systems needed repair or replacement. Residents rejected a proposed centralized sewer system that would have cost $3.1 million.    


SOLUTION 

The community opted to repair or replace 133 of the existing 185 treatment systems with the water and sanitation district serving as the operator/manager of the upgraded and new facilities. 


RESULTS

"The decentralized wastewater option was less than half of the projected cost of central sewage treatment for the 133 homes served by repaired or replaced systems. Sewage surfacing and cesspool discharges throughout the community no longer occur. Post-construction groundwater monitoring found nitrate levels at 1 mg/L or less in the project area, far below the 10 mg/L standard for groundwater used as drinking water."

Learn More

EPA Case Study

OTTER TAIL LAKE, MINNESOTA

PROBLEM 

The community around Otter Tail Lake in western Minnesota saw a decline in lake water quality. An environmental assessment revealed that substandard wastewater systems, untreated sewage discharges to surface waters and intensive shoreline development contributed to high levels of phosphorus in the lake, causing elevated algae growth and an overall decline in water quality.   


SOLUTION 

The community formed a management district to identify and repair/replace malfunctioning systems and manage the wastewater treatment systems of four townships situated on six area lakes.


RESULTS 

After the program’s inception in 1984, the OTWMD upgraded 850 treatment systems. The district installed 16 clustered systems for 260 connections and repaired or replaced 590 other treatment systems. The district also serviced a total of 350 other systems, including full inspections, septic tank pumping and installation of new tank risers and covers. In the past decade, the district has replaced or repaired only 17 systems (out of nearly 1,500).  


The district’s actions resulted in documented water quality improvements. For example, surface water monitoring of the lake has revealed declining phosphorus and algae concentrations and overall improved water quality. Nitrate concentrations have dropped from 1 mg/L to approximately 0.2 mg/L; Secchi depth has increased from 2.4 feet to about 4 feet.

Learn More

EPA Case Study

KEUKA LAKE WATERSHED, NEW YORK

PROBLEM 

Approximately 20,000 residents in the Keuka Lake watershed rely on groundwater and the lake for their drinking water. Nearly all of the residents in the watershed also depend on individual wastewater systems that are densely positioned and that discharge to the soil for treatment. However, testing revealed that poorly maintained individual onsite systems were contributing excessive levels of bacteria to the lake and contaminating drinking water wells. 


SOLUTION 

Eight municipalities formed a regional watershed cooperative that implemented a uniform permitting and inspection program to identify and repair or replace malfunctioning treatment systems. As a result, Keuka Lake’s water quality ranks among the highest of the water bodies in the Finger Lakes region. 


RESULTS 

Water quality monitoring results indicate very good lake conditions, though runoff from stormwater and agricultural sources after storm events can result in high bacteria levels. The relatively clear water in the lake contains low nutrient levels and supports excellent fisheries. Monitoring results from 2005–2009 show lake water quality improving or holding steady for nearly all parameters. The local lake association attributes this progress, in part, to the septic system inspection program.  

Learn More

EPA Case Study