290 likes | 425 Views
Status Quo Assessment of Wastewater Ponding Systems. Presentation Road Map…. 1. Background 2. Study Methodology 3. Study Findings 4. Why Ponds. Background…. Free State Act. sludge, trick. filters, RBCs and Ponds Complaints relating to the failure and/or poor condition
E N D
Presentation Road Map… 1. Background 2. Study Methodology 3. Study Findings 4. Why Ponds
Background… • Free State • Act. sludge, trick. filters, RBCs and Ponds • Complaints relating to the failure and/or poor condition • Locality and operation – unacceptable and create environmental and health risks • Insufficient information wrt operational status & effectiveness of management thereof by WSAs • Circumstances in other parts of SA??? • ID and understand status of pond systems in SA • Develop Practical Guidelines
Management Meetings… • Management questionnaire • Included queries related to: • Effluent source • Population served (size and status) • Records of pond system design • Understanding of the status of the pond system • Safety aspects (e.g. fence, location, clothing) • Monitoring • Staff availability and skills, basic needs met (water)
Site Visits… • Assessment of pond system using modified/updated questionnaire • Collection of GPS co-ordinates (location) • Photographing the site • Number of ponds, shape of ponds, type of ponds and flow patterns • Location relevant to nearest housing • Capacity – measured either by a measuring tape or the foot method • Measurement of sludge depth • Maintenance aspects – screenings, grass on linings or within ponds • Safety aspects – enclosure, vandalism, etc • Origin of effluent – nightsoil: bucket washing, connection • Final effluent – discharged, irrigated, recycled/re-used • Water quality – systems discharging or irrigating
Wastewater Pond System Assessment Tool… • WSAs Self Assessment of the Wastewater Pond System • Assist in planning (short/medium or long term needs) • Identify areas of risks and needs (short/medium or long term needs) • Assist in identifying and tracking emergency issues • Assist in understanding of required maintenance
Tool Components… • General Assessment • Standardized assessment • Can be completed by range of people with same outcome • Allows for comparative assessments • Guides proactive intervention • Risk Assessment • Looks at Key Areas of Risk • Guides attention to Proactive Intervention (i.e. prevent incidents before they arise) Tool has been modified to make easier to use
Allocation of Weights/Score… If the issue may/will lead to:
Weighting Score Consequence of the Risk Risk Orientated Weighting… • Weighting scores
Wastewater Pond Assessment Tool… Effective & Sustainable Wastewater Pond Systems Safety Maintenance Water Quality Monitoring Operation and Performance Supervision and Management Design
Assessment Categories… • Design (lining, depth, etc) • Maintenance (screenings removal/handling, housekeeping, etc) • Operation and Performance (flow rates, population served, etc) • Water Quality Monitoring (parameters, frequency, effluent standards, etc) • Supervision and Management (assigning responsibilities, checks, etc) • Safety (fencing, “no entry” signs, etc)
Tool Users… • Likely to be completed by: • Supervisor • Superintendent • Could be completed by process controller BUT may not be able to read/write (can still provide info to supervisor/superintendent) Responsibility ultimately lies with Head of Water/Water Quality Manager or Technical Manager
General Findings… • Design • Systems well designed • Lack of knowledge regarding upgrading options • Operation and Performance • Desludging not done poor performance • Some systems discharging to rivers and/or environment • Maintenance • Poor
General Findings (cont)… • Water Quality Monitoring • No monitoring • Supervision and Management • No records • Safety • Not well secured, vandalism • Community awareness problematic • Operator basic need (e.g. drinking water, shelter) and sanitary facilities
Animals drowning within ponds Pond near dwellings Sludge layer measurement Final Effluent flowing to a dam
Challenges • Urbanisation • Bucket eradication • More capacity required • More possible overflow pollution • More protection costs • More management costs
Why consider Ponds? • Remove organic matter and solids • Simple construction with relatively low capital • High level of disinfection achievable • Simple process operation – an appropriate technology • Solar powered aeration/disinfection
Why consider Ponds • Minimal (or nil) mechanical/electrical equipment • Minimal labour requirement without requirement for sophisticated technical training • Simple process operation – an appropriate technology