SEWAGE SYSTEM SOLUTIONS Current Issues in Ontario & Case Studies of Innovative Approachesto Remedy Failing Systems

Marie-Christine Bélanger Rick EsselmentDirector Vice-PresidentOntario Onsite Wastewater Association Ontario Onsite Wastewater Association

October 7th 2013Hamilton, Ontario

Content

Introduction Onsite sewage treatment Some statistics Problems encountered in the field Solutions Other jurisdiction – Case studies

Introduction

The idea of this presentation came after a tour of MMHA and MOE in the province of Qc to meet Qc MOE and the BNQ relative to the adoption of the CAN/BNQ in the OBC Part 8.

To protect and promote the benefits and value of onsite and decentralized wastewater

management through education, improved standards of practice and advocacy

for sound policies across the province

Onsite Sewage Disposal Systems?

Onsite Wastewater Treatment Systems

Some Statistics

0-1 1-22-7

7-15>15

5% 6%5%

70%67%

Failure rate of conventional systems

Ref: USEPA

55% of failures are related to poor maintenance

Conventional systems are not permanent infrastructures, but technologies can be!

Some Statistics

Poor design6%

Poor construction

9%Inaccurate

soil/site assessment

19%

Insufficient maintenance

21%

age > 10 years45%

Causes of Failure

Ref: USEPA

It is time for a change of context

We have an opportunity to do better

Distribution Boxes

If something doesn’t seem quite right…it usually isn’t, so keep looking

What are we waiting for?

What are we waiting for?

Case Study

3 bedroom

2200 sq ft home50 year old septic system

Challenge

No signs of bed failure

6 m from house to property line

Leaching field in this area

OBC requires 5 m to dwelling and 3 m to property line

Case Study

3 bedroom

1100 sq ft home50 year old septic system

Case Study

Outside of tank no connection to leaching field Septic tank has failed

Challenge

Leaching field is failed

10 m from house to property line

Leaching field in this area

No room for leaching field or mantle

Case Study

3 bedroom

1100 sq ft home 50 year old septic system

Case Study

Heavy clay soil

Failed leaching field Field envelope is 70 m²

Possible solutions under the current OBC

Holding tanks

Compliance alternatives (OBC 11.5) Same system w/o compliance with horizontal

setbacks Treatment unit with a reduced vertical clearance

and smaller footprint (area bed and shallow buried trenches)

Offering value-added solutions designed to perform and last

Protecting shared water resources

Ensuring a cleaner environment for communities

and families

What should we be seeking?

Case Studies from different jurisdictions

Cluster installation (St-Joseph-de-Kamouraska)

Small lots and sensitive zone (Lac-Beauport)

Case Study #1St-Joseph-de-Kamouraska

Alternative to Conventional Sewer and

Decentralized WWT Cluster Installation

St-Joseph-de-Kamouraska Municipality

Rural municipality in the Lower St-Lawrence region Population: 428 Territory: 86,5 km² Density: 5,1 inhabitants/km2

Case Study #1

Context

80 residences and businesses

(260 inhabitants serviced) 

Daily flow: 76 m3

Contaminated individual drinking

water wells (too small lots, failing septic installations)

Shallow bedrock and floodplain

Limited available space near the urbanized perimeter to implement a conventional approach

Cost of a conventional solution consisting of aerated lagoons connected to the municipal sewer system? 2 M$

Rivère-du-Loup river

St-Joseph-de-Kamouraska

Solution

Advanced treatment Biofilter

technology with effluent

discharge into the

Rivière-du-Loup river 

15 mg/L in TSS and in BOD5

50 000 CFU/100 ml in FC

Complete installation

1 septic tank with effluent filter per residence small diameter collection system (2,500 linear meters) 5 treatment sites spread out in the municipality for a total of

80 Biofilter units (↓ the costs of the collection system)

Rivère-du-Loup river

St-Joseph-de-Kamouraska

Project

Executed in the summer of 2001

Cost: $950,000 Collection work: $600,000

Treatment: $350,000 (septic tanks and Ecoflos)

Grant: Quebec’s Programme des eaux vives Non-subsidized portion assumed by the

municipality via a 20-year loan

Costs to citizens: $373/year

Site #1 (30 biofilters – 3 clusters of 10 units)

Operations

Operational cost: $300/residence per year

(including filtering media replacement)

Low energy: 450 kWh/month ($30-35/month)

No intervention needed on the network

No water infiltration

Performance

True average flow: 53 m3/d – 70% of the design Q

Parameters InfluentSummer effluent (T > 7oC)

Winter effluent(T < 7oC)

Discharge criteria

MES (mg/L) 47 ± 12 5 ± 3 3 ± 2 15

DBOC5 (mg/L) 157 ± 42 3 ± 2 5 ± 2 15

NH4 (mg/L) 39 ± 6 2,6 ± 2,5 5,7 ± 1,7 --

CF (UFC/100 ml) 1 600 000 18 000 22 000 50 000

n 29 73 20 s. o.

Treatment Performances (2002 to 2012)

Case Study #2Lac-Beauport

Highly Treated Effluent to Allow Direct Surface Discharge

Lac-Beauport

Regional municipality located 20 kilometers from downtown Quebec City

Population: 6145 Territory: 64 km² Density: 98 habitants/km2

Case Study #2

Context

Currently 9 high-value properties, some lakefront, with failing conventional septic systems

Runoff waters to Beauport Lake No possibility of installing a new leaching field on any

of the properties (small lots and shallow rock) – only option was holding tanks

Limited space between residences Older residences with extensive existing landscaping

Context

Quebec regulation only allows holding tanks as a last recourse

Municipality desperate for a different solution –

concerned about impact of holding tanks on property value and the complexity of their maintenance

Quebec regulation allows for direct discharge for septic system conditional to disinfection and/or P removal depending on the sensitivity of the receiving environment

Project started in the Fall of 2012

Solution Phosphorus Removal Unit

with direct surface discharge

to ditch ending in Beauport

Lake

 <10 mg/L in TSS and in BOD5

<0.3 mg/L P

<200 CFU/100 ml in FC

Complete installation per residence

1 primary reactor + 1 DpEC Unit + Biofilter + DiUV Bypassed the existing disposal field Modularity allowed for greater flexibility regarding distances

to respect

System Installed

Ptot: 0,4 mg/L Ptot: 0,1 mg/L

Ptot: 0,1 mg/L

Tertiary treatment level BIV, DII, PII

Average Performance

Parameters Septic tank effluent DpEC effluent Ecoflo effluent DiUV effluentTSS (mg/L) 50-90 17 2 2

CBOD5 (mg/L) 120-200 62 2 2P tot (mg/L) 5-14 0.3 0.03 <0.03

FC (UFC/100 mL) 500k-2M 18254 224 <0.3pH 6-9 8.2 7.5 7.5

Other possible configurations

System costs

Cost for phosphorus removal unit: $8,995 (Primary reactor and

EC unit)

Excavation work: Average of $10,000

Complete treatment chain: $15,000 (including Biofilter,

phosphorus removal unit and all systems components)

System installed

Light system requiring regular machinery

Single-day installation for each treatment plant

Remediation Costs – Holding Tank

Average cost of septic tank: $3,000

Average cost of excavation work: $2,500

Average cost of pump-outs: $500 to 800 per

pump out/month (to treatment plant)

Holding tank should be a last resource and temporary solution – not a long-term sustainable solution

Electricity and replacement of the aluminum plates

Operation & Maintenance Costs

20$ / month

12$ / month

<10$ / month

Conclusion

Highlight of existing problems and applicable solutions

Need to start talking about how to bring them (problems and solutions) together

Come to OOWA conference to continue the discussion on how to implement these solutions

Thank you!Questions?

Treatment classes

Basic level (B)*

TSS CBOD5

B-I 100 150

B-II 30 25

B-III 15 15

B-IV 10 10

* In mg/L

Treatment Classes

Treatment classes

Disinfection (D)UFC/100 mL

Phosphore (P)

mg/L

Nitrogen (N)

FC ou E. Coli* P total N total

D-I 50 000

D-II 200

D-III ND (median < 10)

P-I 1,0

P-II 0,3

N-I 50%

N-II 75%

Summary of CAN/BNQ Standard