DOLOMITE RISK MANAGEMENT PROCEDURE FOR IRENE GLEN HOMEOWNERS ASSOCIATION

Transcription

1 DOLOMITE RISK MANAGEMENT PROCEDURE FOR IRENE GLEN HOMEOWNERS ASSOCIATION INDEX 1. INTRODUCTION 1 2. INFRASTRUCTURE MANAGEMENT PLAN 1 3. RESIDENCE MANAGEMENT PLAN 3 4. EMERGENCY REACTION PLAN 6 5. MONITORING 6 6. DATA BANKING 7 7. REASSESSMENT 7 8. DETAIL DRAWINGS 8 7 MARCH 2002

2 IRENE GLEN HOMEOWNERS ASSOCIATION DOLOMITE RISK MANAGEMENT PROCEDURES 1. INTRODUCTION The purpose of this Dolomite Risk Management Procedure Report is to ensure that the following regulations are applied to minimize the possibility of subsidence in accordance with the Dolomite Risk Management Policy and also to establish an effective Emergency Reaction Plan in the event of an emergency. 2. INFRASTRUCTURE MANAGEMENT PLAN The Irene Glen Homeowners Association will manage and control the infrastructure regarding the following: 2.1 STORMWATER The natural surface runoff of stormwater should as far as possible not be altered substantially nor should it be obstructed and allowed to infiltrate into the ground especially at concentrated positions and over extended periods. All boundary walls shall have sufficient drainage holes such as 50 mm diameter holes at ground level, spaced at 1.0 m centre-to-centre, or alternative methods approved by the Irene Glen Homeowners Association. Any concentrated stormwater shall be dispersed to the natural surface drainage pattern as quickly as possible. The stone pitching on the outlet side of the culverts underneath the roads must be extended to disperse the stormwater in a sheet flow pattern as far as possible as the case was for the pre-development stage. All the stormwater culverts underneath the roads shall be inspected periodically and be cleaned of any obstructions such as silting, tree stumps etc. 1

3 2.2 SEWERAGE RETICULATION Since the sewerage reticulation is a Solids-Free Sewer System consisting of small diameter pipes, a camera inspection is not possible and it is therefore recommended that a visual inspection at surface level be performed periodically during peak times for blockages and leaks. The sanitation system shall not incorporate soak aways (french drains). All the septic tanks will be connected to the sewerage reticulation. 2.3 WATER RETICULATION The reticulation conforms to normal specified engineering standards for water reticulations. The Rand Water bulk meter must be reconciled with the individual property water meters at least once a month. Any water loss not accounted for must be investigated and rectified. A visual inspection to detect unnaturally wet areas indicating possible leaks must be done periodically along the entire water reticulation. All the meters must also be checked periodically where practical when there is no water usage for possible leaks in the system. Rand Water must inspect the Rand Water main across the eastern side of Irene Glen on a regular basis and these reports must be submitted to the Irene Glen Homeowners Association. 2.4 GENERAL All the holes drilled by the Geotechnical Engineer for the Dolomite Stability and Geotechnical Investigation are to be plugged according to the detail drawing to prevent the ingress of stormwater. The positions must be co-ordinated. The existing borehole on Portion 247 should be sealed and should not be used without prior detailed investigations by the necessary authorities. 2

4 3 RESIDENCE MANAGEMENT PLAN The homeowners of the houses already constructed must be made aware of the following regulations. Every effort must be made by them to comply with the following, however if this is not possible, it must be subject to the approval of the Irene Glen Homeowners Association. New homeowners should comply with the following: Any alterations after construction or deviations during construction must be approved by the Plan Approval Committee of the Irene Glen Homeowners Association. 3.1 PLUMBING A water meter and valve must be installed at all vacant stands. Water pipe entries into buildings shall be in accordance with the attached detail drawings. Sewer pipes through walls shall be sleeved to permit relative movements. All sewer and water pipes and fittings shall be provided with flexible, watertight joints. No plumbing or drainage pipes shall be placed underneath floor slabs or be encased in concrete. Only exceptional cases will be allowed where they are placed in sleeves and only with the prior approval from the Irene Glen Homeowners Association. WC pans shall be provided with a flexible connection at the junction with the outlet pipe. The minimum cover of water pipes shall be 500 mm. Wherever practical, service trenches shall not be excavated along the length of buildings within the first 3.0 m beyond the perimeter of the buildings. The fall of all the above service trenches shall be away from the buildings. Gardeners should be aware of all the positions of water, sewer and irrigation pipes. The wet-service as-built plans of each property must be lodged with the Irene Glen Homeowners Association for record and data banking purposes. 3

5 3.2 STORMWATER DRAINAGE If temporary ponding of stormwater is inevitable, the area affected shall be lined with a permanent impervious membrane such as a concrete lining with sealed joints or other alternative methods approved by the Irene Glen Homeowners Association. Any natural pond or water feature shall be rendered impervious with a permanent reinforced concrete lining without joints and be monitored for any loss of water. As for the Infrastructure Maintenance Plan, all boundary walls shall have sufficient drainage holes such as 50 mm diameter holes at ground level, spaced at 1.0 m centre-to-centre, or similar approved by the Irene Glen Homeowners Association. Rainwater down pipes shall discharge into concrete lined drainage channels (with sealed joints), which discharge the stormwater at least 1.5 m away from the buildings. If gutters with rainwater down pipes are not provided, a 1.5 m wide concrete apron (minimum) shall be provided (or alternative methods approved by the Irene Glen Homeowners Association). The ground immediately against the building (or concrete apron) shall be shaped to fall in excess of 75 mm away from the building over the first 1.5 m (minimum) beyond the perimeter of the building in order to drain stormwater freely away from the building (or alternative methods approved by the Irene Glen Homeowners Association). Retaining walls shall either have weep holes if exposed to the outside or if this is not possible a subsurface drainage system must be installed to prevent the built-up of groundwater, and must be connected into the sewerage reticulation downstream from the septic tank, since no underground stormwater system exists. All stormwater channels within 10 m of a building shall be lined with a permanent impervious membrane such as an engineered Bentonite clay lining or any other approved alternative method. This is specifically applicable to the natural drainage course of the region on the western side of Irene Glen. 4

6 3.3 SWIMMING POOLS The suitability of the area for a swimming pool as well as the immediate surroundings must be investigated prior to construction. It is the Homeowners responsibility to ensure that the construction of the swimming pool is of premium strength and integrity considering possible ground movement in dolomite areas. Backwash from swimming pools shall be discharged into the sewerage reticulation downstream from the septic tank. A subsurface drainage system shall be installed according to the detail drawings, which must be connected to the sewerage reticulation downstream of the septic tank where practical. This is only applicable to new swimming pools, since this is not possible for existing swimming pools. Any air entering the pipe system of the swimming pool or excessive refilling of the swimming pool level could indicate a leak and must immediately be inspected and the leak must be repaired. All water pipes, pumps and connections should be installed either in the open, on the surface, in service canals or other approved methods where these may be inspected or repaired without access problems..4 GENERAL All the holes drilled by the Geotechnical Engineer for the foundation investigations of the individual properties are to be plugged according to the detail drawing to prevent the ingress of stormwater. The positions must be co-ordinated. Blasting of rock pinnacles for foundation purposes should not be allowed without the necessary investigation and report by an appropriate qualified person. 5

7 4 EMERGENCY REACTION PLAN In the event of an emergency, any one of the current directors must be contacted immediately with the relevant details such as: Locality of occurrence Stand number Injuries sustained and number of people Damage to infrastructure and houses Possibility of further collapse to structures The originator or contacted person as above, can contact the required emergency reaction teams who could be any of the following: Fire Department Centurion Ambulance Services Hospitals Unitas Police The appropriate professionals will be contacted to determine the remedial measures required. Possible emergency measures could be: 5 MONITORING The closing-off of water valves to the affected area. Demarcation and fencing-off of the affected area Diversion of the traffic Necessary instructions to nearby houses Cut-off electricity supply to the affected area. The Irene Glen Homeowners Association should investigate the affected area before the services are reconnected All the prescribed inspection and control requirements must be monitored on a regular basis. These reports must be tabled at the Homeowners Association board meetings for analysis and remedial measures to be proposed where necessary. An independent consultant may be appointed to audit the Dolomite Risk Management Policy and Procedures when necessary. 6

8 6 DATA BANKING All the data from the specified inspections and tests must be recorded and kept in a safe archiving system for both the infrastructure and residences. 7 REASSESSMENT It is recommended that this Dolomite Risk Management Report together with all the inspection and test data be evaluated on a regular basis and that the necessary adjustments be made based on reassessments regarding aspects such as new technologies and inventions. 7

9 8. DETAIL DRAWINGS 8