Constructed wetlands are built to mimic natural wetlands for the treatment of wastewater, mostly for polishing. However, in certain rural areas, they have found applications in nutrient removal, BOD/COD reduction, sludge treatment and other applications as technology evolves.
Are there any special design features for sludge handling and biogas generation in constructed wetlands? What are the existing national/regional/international regulations on standardization of design and construction as this has been a major constraint over the years?
I am doing the same research, when I reach I will share with you. good luck
Bassey
The link below might give you some ideas.
As far as the use of biosolids (treated sewage sludge) in the construction of a wetland . I have seen biosolids utilized as the growth substrate in a newly constructed wetland. In the US to do this the biosolids must meet high level pathogen treatment(Class A), meet certain other pollutant requirements (low metals) and meet stability requirements.
Bob
https://www.epa.gov/wetlands/constructed-wetlands
I concur with the above response.
As far as permitting goes:
Typically, an artificial impoundment can be a reuse site (for the reuse of discharges from other treatment systems in addition to the biosolids reuse situation mentioned in the above response).
Discharges to the wetlands/artificial impoundment as a reuse (of reclaimed water) site: Constructed wetlands too have (in our case in NV) water quality standards (WQSs) established ergo discharges to/or use of these wetlands should comply with the WQS just like any other situation with specific attention given to Residual Chlorine, temperature difference besides other constituents (toxic pollutants) if fish and other aquatic life is expected to be not harmed. Often such discharges may also end up needing /opt for mixing zone considerations (still obligated to ensure the safety of the aquatic life (ex: safety of fish that may be present in the impoundment should be considered) as well as other designated uses of that specific impoundment . Also regulations/limits of expected standards vary depending on the access levels to the wetlands - as in if no human contact is expected then discharges to the wetlands can have little higher Fecal Coliform vs. Coliform levels have to be more stringent when human contact / use by live stock is expected. Requirement to NOT degrade the existing water quality (of the impoundment) is a default expectation too.
Assuming the question is about adapting/using an artificial wetland alone as a treatment option:By definition wetlands are aimed to support aquatic/wild life, then it follows that both the design and operations/maintenance should incorporate consideration/provisions for periodical Nutrient removal (especially P) etc,. too besides making a case for treatment and ensuring support for all the designated uses of that particular impoundment. Additionally one has to check whether the impoundment has a potential to be hydrologically connected to either the groundwater or nearby surface waters; and monitoring regimen should be chosen so as to ensure there is no negative impact (in the water quality) from such potential interference.
HTH
Not a design expectation source, but thought this would help in setting the design goals for an artificial wetland:
https://www.epa.gov/cwa-404/national-guidance-water-quality-standards-wetlands
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