AU2004100596A4

AU2004100596A4 - Blockage protection for sewer and stormwater pipe networks

Info

Publication number: AU2004100596A4
Application number: AU2004100596A
Authority: AU
Inventors: John Grundy
Original assignee: SOUTH EAST WATER Ltd
Current assignee: SOUTH EAST WATER Ltd
Priority date: 2004-07-23
Filing date: 2004-07-23
Publication date: 2004-08-26
Anticipated expiration: 2012-07-23
Also published as: AU2004100596B4

Description

P00o Section 29 Regulation 3.2(2)

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION INNOVATION PATENT Application Number: Lodged: Invention Title: BLOCKAGE PROTECTION FOR SEWER AND STORMWATER PIPE

NETWORKS

The following statement is a full description of this invention, including the best method of performing it known to us: BLOCKAGE PROTECTION FOR SEWER AND STORMWATER PIPE

NETWORKS

The present invention relates to a device, a system and a method of monitoring potential fluid rise in manholes providing access to a stormwater or sewer pipe network that may indicate a blockage or partial blockage in the network before such fluid banks up and flows out of the manholes into the general environment or possibly back into dwellings or other buildings causing environmental or property damage.

Stormwater and sewer pipe networks are from time to time subject to partial or complete blockage for various reasons including debris build up, tree roots infiltrating into the pipe network, deterioration of the pipe and possibly partial collapse of the pipes at a locality. Such events in the past have caused liquid build up behind the blockage (or partial blockage) such that the liquid may bank back into and out of manholes or back into dwelling and other buildings causing considerable damage. In many such cases, if the event is detected earlier enough, fluid flow might be diverted around the blockage or partial blockage and the blockage cleared or the pipe repaired to avoid the catastrophic outlet of sewer liquids and stormwater into the environment.

The objective therefore of the present invention is to provide a means and a method of detecting such potential events at a reasonably early stage in a reasonably economic manner such that remedial action can be taken before liquids are undesirably released into the environment.

According to a first aspect of this invention, a method is provided of detecting blockages in a stormwater or sewer pipe network having a plurality of manholes providing access thereto, said method involving installing fluid height sensing means in at least one said manhole for detecting fluid rising in the or each said manhole to a predetermined level indicative of a blockage in said pipe network downstream of a said manhole containing said fluid height sensing means, transmitting automatically the or each said fluid height sensing means to monitoring means, signals indicative of said fluid rise to said predetermined level.

In accordance with a second aspect, the present invention also provides a monitoring system for a stormwater or sewer pipe network having a plurality of manholes providing access to said pipe network, said monitoring system 2 including at least one fluid height sensing device having installation means enabling the or each said fluid height sensing device to be installed in a said manhole for determining, in use, fluid rise in said manhole exceeding a predetermined limit, said monitoring system further including transmission means operably associated with the or each said fluid height sensing device to transmit signals therefrom when said fluid height increases beyond said predetermined limit in a said manhole to a distant monitor of such signals.

Conveniently the or each said fluid height sensing device includes a float switch and said installation means is configured to, in use, locate said float switch in a said manhole at said predetermined height. Preferably the monitor includes a computer controller arrangement located at a site distant from the manhole.

According to a still further aspect, the present invention also provides a fluid level sensing device for installation in a manhole providing access to a pipe network of a stormwater or sewer system, said device including fluid height sensing means, installation means for installing said device in a said manhole whereby said fluid height sensing means is located at a predetermined height in said manhole, and said device further including signal transmission means for transmitting signal means indicative in use of fluid height exceeding said predetermined height in said manhole to monitoring means distant from said device.

By providing a fluid height sensing device or a plurality of such devices in at least selected manholes that provide access to the sewer or stormwater pipe network, it is possible to sense fluid rise in the manhole quickly at some distant centralised location such that remedial action can be commenced to prevent or at least limit the damage that might be caused by liquid back flow into the environment.

By the term "manhole" used throughout this specification including the annexed patent claims, it is intended, to identify any substantially vertical access hole, conduit, or the like that enables access to the underground stormwater or sewer pipe network.

A preferred embodiment will now be described with reference to the annexed drawings, in which: Fig 1 is a schematic illustration of part of a stormwater or sewer pipe network including access manholes and showing a device in accordance with a preferred embodiment of the invention installed in one of the manholes; Fig 2a is an illustrative side elevation view of a device in accordance with one preferred embodiment of the present invention installed on a manhole wall; and Fig 2b is a front elevation view of the device shown in Fig 2a.

Fig 1 illustrates schematically and by way of example a portion of an underground stormwater or sewer pipe network 10 comprising pipes 11 with manhole access means 12 suitably distributed at spaced locations in the network.

A plurality of drain pipes 13 will normally feed liquids into pipe network 10 from buildings 14 or other above ground localities as needed. Fig 1 further illustrates a blockage or partial blockage, in this case via a build up of debris 15 in the pipes 11, that may cause a back up of liquids in the pipes 11 including drain pipes 13 upstream of the blockage 15 and in manholes 12 upstream of the blockage 15. It will of course be appreciated that the blockage 15 does not need to fully block the pipes 11 for a back up of liquids to occur upstream thereof and depending on liquid flows in the pipe network 10, liquids may bank up and overflow back into buildings and generally into the environment via upstream drain pipes 13 and upstream manholes 12.

Fig 1 further illustrates a liquid height sensing device 16 in accordance with this invention installed in at least one access manhole 12 with self contained signal processing equipment 17 and transmission means 18 including an antenna means for transmitting a signal to a monitoring arrangement 19 indicative of the liquid height in the manhole 12 reaching a predetermined height indicative of a downstream blockage (partial or complete) in the pipe network 10. In the situation where multiple devices 16 with associated signal processing and transmission means 17, 18 are installed in different manholes 12, the information transmitted when a predetermined liquid height level is sensed in a particular manhole 12, includes information indicative of the manhole 12 itself.

Conveniently the signal processing means 17 includes a mobile phone modem which can convert a digital input signal (the output of the float switch or liquid height sensing device 16) into a text string compatible with the GSM mobile phone network short message service (SMS). The transmission means 18 conveniently includes a mobile phone antenna suitable for transmitting and receiving signals in a totally enclosed underground environment such as an access manhole 12 leading to an underground pipe network 10. As is apparent from Fig 1, the monitoring arrangement 19 may simply be a suitable mobile phone 20 configured to receive the transmitted signals which is then acted upon by a trained operator 22. The monitoring arrangement 19 may alternatively (or in addition) be a dedicated computer system 21 to process incoming signals, particularly where multiple signals might be expected from different access manholes 12 to establish the likely site of a potential blockage. The monitoring arrangement 19 may also include visual or audible alarm means.

Figs 2a and 2b illustrate one preferred form of a liquid height sensing device 16, contained signal processing equipment 17 and transmission means 18, including a mounting arrangement 23 for installing same in a manhole 12.

The illustrated equipment includes a bracket 24 mounted to a wall 25 of the manhole 12, the bracket 24 being configured to receive a leg of an L shaped bracket 26 -secured to a back plate 27 supporting a container 28 for mounting the signal processing equipment 17 and protecting same against externally applied damage including ingress of undesirable liquids. The equipment further includes a float switch 16 supported by a cable 29 that transfers signals from the float switch 16 to the signal processing equipment 17 supported within the container 28. The float switch 16 is activated by liquid reaching the oval float container such that it topples over from the illustrated vertical position towards a horizontal position supported on the rising liquid surface. Such action triggers the switch and conveys an indicative signal via cable 29 to the processing equipment 17.

The bracket 24 is positioned on the manhole wall 25 at a desired height and the length of the cable 29 is selected to position the float switch 16 at a desired height in the manhole 12 such that activation of the float switch 16 will be indicative of a probable blockage or partial blockage in the pipe network 10. Preferably hand grip bars 30, 31 are provided secured to the back plate 27 to assist with lifting and manoeuvring the equipment into an operative position (as illustrated) or out of the manhole 12 when servicing might be required.

Conveniently, the signal processing equipment includes software which enables the system to function as desired as well as performing health checks such as communication signal strength, battery capacity, as well as being able to receive incoming status requests from the user. The equipment is preferably powered by a self contained battery having sufficient capacity to operate the system for at least six months and preferably at least twelve months before replacement or recharge.

Claims

1. A method of detecting blockages in a stormwater or sewer pipe network having a plurality of manholes providing access thereto, said method involving installing fluid height sensing means in at least one said manhole for detecting fluid rising in the or each said manhole to a predetermined level indicative of a blockage in said pipe network downstream of a said manhole containing said fluid height sensing means, transmitting automatically the or each said fluid height sensing means to monitoring means, signals indicative of said fluid rise to said predetermined level.

2. A monitoring system for a stormwater or sewer pipe network having a plurality of manholes providing access to said pipe network, said monitoring system including at least one fluid height sensing device having installation means enabling the or each said fluid height sensing device to be installed in a said manhole for determining, in use, fluid rise in said manhole exceeding a predetermined limit, said monitoring system further including transmission means operably associated with the or each said fluid height sensing device to transmit signals therefrom when said fluid height increases beyond said predetermined limit in a said manhole to a distant monitor of such signals.

3. A monitoring system according to claim 2 wherein the or each said fluid height sensing device includes a float switch and said installation means is configured to, in use, locate said float switch in a said manhole at said predetermined height.

4. A monitoring system according to claim 2 or claim 3 wherein the monitor includes a computer controller arrangement.

5. A fluid level sensing device for installation in a manhole providing access to a pipe network of a stormwater or sewer system, said device including fluid height sensing means, installation means for installing said device in a said manhole whereby said fluid height sensing means is located at a predetermined height in said manhole, and said device further including signal transmission means for transmitting signal means indicative in use of fluid height exceeding said predetermined height in said manhole to monitoring means distant from said device. DATED this 23rd day of July 2004 SOUTH EAST WATER LIMITED WATERMARK PATENT TRADE MARK ATTORNEYS 290 BURWOOD ROAD HAWTHORN VICTORIA 3122 AUSTRALIA UIP1079AU00 SKP/JC