Barber Wastewater Lagoons - Boise
The Barber wastewater lagoons are located in Boise south and east of the historic town site of Barber, Idaho. The former town site began around 1904, and the lagoon property potentially contained the Barber Mill log pond, railroad spur, and related railroad structures. A blacksmith shop, round house, and coal bin may have also been on the site. The Barber Dam was constructed in approximately 1904 to create a log-holding pond and power generating facility for the Barber Mill.
According to aerial photos, it appears the lagoons were created around 1963. Adjacent development increased through the 1970s and the lagoons served as the primary sewage disposal for the Golden Dawn Estates subdivision, Idaho Shakespeare Festival, and Riverstone International School for decades before connecting to the Boise municipal sewer service. Once the facilities were connected to the city sewer, the wastewater lagoons were no longer needed.
The Idaho Foundation for Parks and Lands recently purchased the property and sought assistance from DEQ’s Brownfields Program. The property is approximately 12 acres. The foundation would like to convert the property to open space/park space for use by the public. Multiple reuse plans are being considered and include habitat restoration, walking paths, picnic areas, casting ponds, a potential stream from Barber Pool, and many others.
Site Investigation Process
Multiple site investigations have been conducted on the property. In October 2007, a Phase I environmental site assessment (ESA) found multiple recognized environmental conditions (RECs) associated with sewage effluent and potential related residues from pharmaceuticals and personal care products. The Phase I ESA recommended ground water well installation, ground water monitoring, and sampling of wastewater lagoon sludge and wastewater.
A Phase II ESA was conducted in October 2007 to evaluate the potential for contaminants of concern (COCs) that may be associated with the property’s use to store wastewater. COCs looked for as part of the investigation included emerging organic contaminants as well as biological, organic, and inorganic parameters.
Overall, ground water from the monitoring wells showed elevated levels of arsenic exceeding the initial default target levels (IDTLs) in all wells. There was also a detection of pentachlorophenol in the fifth monitoring well that slightly exceeded the IDTL.
After the lagoons were no longer in use in late July 2014, another Phase II ESA was conducted, installing new ground water monitoring wells. The old wells and new wells were sampled; in general, the detected COC concentrations have remained stable or even decreased since the 2007 monitoring event.
In addition to the ground water Phase II ESA, a soil and sludge Phase II ESA was conducted in October 2014 and focused on the primary and secondary ponds. Exceedances were found in the primary and secondary pond sludge and in the soil beneath the ponds. Exceedances in the soil included arsenic, selenium, mercury, nitrate, and ammonia.
The DEQ Brownfields Program assisted with preparing a decommissioning plan for the sewer lagoons. The plan outlined the findings from the assessment work and provided a schedule for the final decision on what to do with the sludge. The discussions included keeping the sludge in place and/or spreading out the sludge and planting crops to aid in the uptake of nutrients. This plan would take at least three years and was not a feasible option for the desired reuse of the property.
After discussions with multiple stakeholders, DEQ decided the Brownfields Program could assist with removing the sludge and funded the removal in September and October 2015. A portion of the in-flow piping in the primary pond was found to be Transite, an asbestos-containing material that had to be removed by a specialized company.
The lagoons are now permanently decommissioned and a final closure report provides details on how the closure and decommissioning complied with the approved lagoon closure plan.
- Total assessment funds expended (including 2007 assessment work): $ 65,014.11
- Foundation work: $177,873.58
- Acreage assessed: 12
The mission of the foundation in planning redevelopment of the property is to restrict activities (only noncommercial and nonprofit) so the focus can remain on open space and limited support facilities.
Collaboration was and is crucial to the success of this property. Stakeholders include the Idaho Foundation for Parks and Lands, Shakespeare Festival, Idaho Department of Fish and Game, homeowner associations, US Army Corps of Engineers, Ada County, City of Boise, Riverstone International School, Enel Green Power, private consultants, and citizens.
Various use and restoration ideas have been provided at the stakeholder meetings, including habitat restoration, recreation uses, interpretive kiosks, public art, and fly fishing practice facilities.
The following designs were created by Don Belts and consist of Approach A and Approach B in the master plan for restoration of the Barber Ponds.