Long Pond Flow Control Structure and Flood Mitigation

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The Rennies River watershed has been subjected to major flood events caused by river flooding. One of the earlier major flood events recorded was in 1986 when 110 mm of rainfall caused flooding along Leary’s Brook and Rennies River. Increasing urbanization in the Rennies River watershed, more frequent and intense precipitation events, and anticipated increase in precipitation frequency and intensity due to climate change are expected to result in an increase in risk of flood damage along Rennies River.

The Rennies River Catchment Stormwater Management Plan (RRCSMP) was completed in 2014. On May 26, 2014, Council Directive CD# R2014-05-26/5 recommended the below to address flooding in the area.

To reduce flood risk and take action to safeguard residential dwellings and community infrastructure, the City is proposing to construct a flow control structure across the outlet of Long Pond to help protect areas downstream of Long Pond from flooding as well as associated flood mitigation infrastructure. The additional infrastructure (cast-in-place wall and two earth berms) are intended to mitigate flood damage to nearby infrastructure.

The proposed structure will be located on the downstream side of the Allandale Rd bridge and will allow for pedestrians to cross over the structure via a 3.0m wide walkway.

The project registration documentation will be submitted to the Province to start the Environmental Assessment (EA) process. Work on the detailed design, tendering and construction will not start until after the undertaking is released from EA review.

The City of St. John's wants to inform the public of this proposed project and address any questions or concerns they may have. Please read the FAQs and post any questions or comments in our Discussion area.

Feedback gathered through this project will be included in the City's submission to the Government of NL.


A virtual public meeting is scheduled for December 7th at 7pm. Click here to register.

The Rennies River watershed has been subjected to major flood events caused by river flooding. One of the earlier major flood events recorded was in 1986 when 110 mm of rainfall caused flooding along Leary’s Brook and Rennies River. Increasing urbanization in the Rennies River watershed, more frequent and intense precipitation events, and anticipated increase in precipitation frequency and intensity due to climate change are expected to result in an increase in risk of flood damage along Rennies River.

The Rennies River Catchment Stormwater Management Plan (RRCSMP) was completed in 2014. On May 26, 2014, Council Directive CD# R2014-05-26/5 recommended the below to address flooding in the area.

To reduce flood risk and take action to safeguard residential dwellings and community infrastructure, the City is proposing to construct a flow control structure across the outlet of Long Pond to help protect areas downstream of Long Pond from flooding as well as associated flood mitigation infrastructure. The additional infrastructure (cast-in-place wall and two earth berms) are intended to mitigate flood damage to nearby infrastructure.

The proposed structure will be located on the downstream side of the Allandale Rd bridge and will allow for pedestrians to cross over the structure via a 3.0m wide walkway.

The project registration documentation will be submitted to the Province to start the Environmental Assessment (EA) process. Work on the detailed design, tendering and construction will not start until after the undertaking is released from EA review.

The City of St. John's wants to inform the public of this proposed project and address any questions or concerns they may have. Please read the FAQs and post any questions or comments in our Discussion area.

Feedback gathered through this project will be included in the City's submission to the Government of NL.


A virtual public meeting is scheduled for December 7th at 7pm. Click here to register.

CLOSED: This discussion has concluded.

Please post any questions (please check the FAQs first) or comments here and staff will get back to you as soon as possible.

  • Share At normal level your data shows Long Pond is at 53.2m. During and, I assume immediately following, a 1:100 AEP +30 % rainfall event , this level will rise to a maximum of56.0m. How long will it take the level to return to normal (53.2m)assuming no rain during the period between the achievement of the maximum height (56.0.) and the normal water level? What is that time today with no type flood mitigation structure in place? on Facebook Share At normal level your data shows Long Pond is at 53.2m. During and, I assume immediately following, a 1:100 AEP +30 % rainfall event , this level will rise to a maximum of56.0m. How long will it take the level to return to normal (53.2m)assuming no rain during the period between the achievement of the maximum height (56.0.) and the normal water level? What is that time today with no type flood mitigation structure in place? on Twitter Share At normal level your data shows Long Pond is at 53.2m. During and, I assume immediately following, a 1:100 AEP +30 % rainfall event , this level will rise to a maximum of56.0m. How long will it take the level to return to normal (53.2m)assuming no rain during the period between the achievement of the maximum height (56.0.) and the normal water level? What is that time today with no type flood mitigation structure in place? on Linkedin Email At normal level your data shows Long Pond is at 53.2m. During and, I assume immediately following, a 1:100 AEP +30 % rainfall event , this level will rise to a maximum of56.0m. How long will it take the level to return to normal (53.2m)assuming no rain during the period between the achievement of the maximum height (56.0.) and the normal water level? What is that time today with no type flood mitigation structure in place? link

    At normal level your data shows Long Pond is at 53.2m. During and, I assume immediately following, a 1:100 AEP +30 % rainfall event , this level will rise to a maximum of56.0m. How long will it take the level to return to normal (53.2m)assuming no rain during the period between the achievement of the maximum height (56.0.) and the normal water level? What is that time today with no type flood mitigation structure in place?

    David Winter asked over 2 years ago

    This will require further analysis to extract the information from the hydrology models. CBCL will include the existing and post construction durations to lower the pond level back to the 53.2m normal water elevation in the Environmental Registration documents to be submitted to the Province.

  • Share This newly proposed flood control “weir” and associated downstream berms and walls, is just not justifiable, monetarily, or environmentally. It is taking a hammer to squash a fly. Individual solutions for the small handful of homes at risk of flooding should be investigated instead, and assistance provided to the homeowners. This current plan will do nothing to mitigate groundwater flooding of their basements and ponding of water behind the berms; in fact, it’s likely to create and exacerbate those problems. Homeowners have options – landscaping and flood-proofing mitigations can help keep water out. The river and its fish, bird and mammal populations have no such options. I’m not aware of a single environmental group in favour of this project. All of the hard work and money that the QVRRDF and others have invested in our river ecosystem over the decades will have been for nought if this project goes ahead. We have lived adjacent the river for 25-odd years and notice that even ordinary rainfall now causes the river to rise quicker and higher (flash) than it ever did before during such rains. This has happened just since new housing and business developments in marsh land off Kenmount Road went in, and since the former marsh at the bottom of Winter Avenue was covered in new housing and pavement. It is the city’s own misuse of water-permeable land and floodplain that is the far greater cause of any increased local flooding we see on Rennie’s River. Naturally climate change effects will be piled on top of that. We can’t berm our way out of that dilemma. Berms can and do fail, and in any event, merely push the flood problem further downstream and across the river. You say the concrete and earth structure adjacent to Allandale Road is designed to reduce the height of planned downstream berms on Rennie’s River (from a previously proposed 2.2m height at one location!). Even at half that height it is still a ridiculous and destructive proposal, and the citizens won’t stand for it. You read the room tonight in the public meeting as well as I did. In a similar project in Cape Breton, some previously flooded homeowners opted to accept the continuing risk rather than lose their beloved natural areas to berms. Last I heard, the municipality shelved the project. St. John’s should do so as well. on Facebook Share This newly proposed flood control “weir” and associated downstream berms and walls, is just not justifiable, monetarily, or environmentally. It is taking a hammer to squash a fly. Individual solutions for the small handful of homes at risk of flooding should be investigated instead, and assistance provided to the homeowners. This current plan will do nothing to mitigate groundwater flooding of their basements and ponding of water behind the berms; in fact, it’s likely to create and exacerbate those problems. Homeowners have options – landscaping and flood-proofing mitigations can help keep water out. The river and its fish, bird and mammal populations have no such options. I’m not aware of a single environmental group in favour of this project. All of the hard work and money that the QVRRDF and others have invested in our river ecosystem over the decades will have been for nought if this project goes ahead. We have lived adjacent the river for 25-odd years and notice that even ordinary rainfall now causes the river to rise quicker and higher (flash) than it ever did before during such rains. This has happened just since new housing and business developments in marsh land off Kenmount Road went in, and since the former marsh at the bottom of Winter Avenue was covered in new housing and pavement. It is the city’s own misuse of water-permeable land and floodplain that is the far greater cause of any increased local flooding we see on Rennie’s River. Naturally climate change effects will be piled on top of that. We can’t berm our way out of that dilemma. Berms can and do fail, and in any event, merely push the flood problem further downstream and across the river. You say the concrete and earth structure adjacent to Allandale Road is designed to reduce the height of planned downstream berms on Rennie’s River (from a previously proposed 2.2m height at one location!). Even at half that height it is still a ridiculous and destructive proposal, and the citizens won’t stand for it. You read the room tonight in the public meeting as well as I did. In a similar project in Cape Breton, some previously flooded homeowners opted to accept the continuing risk rather than lose their beloved natural areas to berms. Last I heard, the municipality shelved the project. St. John’s should do so as well. on Twitter Share This newly proposed flood control “weir” and associated downstream berms and walls, is just not justifiable, monetarily, or environmentally. It is taking a hammer to squash a fly. Individual solutions for the small handful of homes at risk of flooding should be investigated instead, and assistance provided to the homeowners. This current plan will do nothing to mitigate groundwater flooding of their basements and ponding of water behind the berms; in fact, it’s likely to create and exacerbate those problems. Homeowners have options – landscaping and flood-proofing mitigations can help keep water out. The river and its fish, bird and mammal populations have no such options. I’m not aware of a single environmental group in favour of this project. All of the hard work and money that the QVRRDF and others have invested in our river ecosystem over the decades will have been for nought if this project goes ahead. We have lived adjacent the river for 25-odd years and notice that even ordinary rainfall now causes the river to rise quicker and higher (flash) than it ever did before during such rains. This has happened just since new housing and business developments in marsh land off Kenmount Road went in, and since the former marsh at the bottom of Winter Avenue was covered in new housing and pavement. It is the city’s own misuse of water-permeable land and floodplain that is the far greater cause of any increased local flooding we see on Rennie’s River. Naturally climate change effects will be piled on top of that. We can’t berm our way out of that dilemma. Berms can and do fail, and in any event, merely push the flood problem further downstream and across the river. You say the concrete and earth structure adjacent to Allandale Road is designed to reduce the height of planned downstream berms on Rennie’s River (from a previously proposed 2.2m height at one location!). Even at half that height it is still a ridiculous and destructive proposal, and the citizens won’t stand for it. You read the room tonight in the public meeting as well as I did. In a similar project in Cape Breton, some previously flooded homeowners opted to accept the continuing risk rather than lose their beloved natural areas to berms. Last I heard, the municipality shelved the project. St. John’s should do so as well. on Linkedin Email This newly proposed flood control “weir” and associated downstream berms and walls, is just not justifiable, monetarily, or environmentally. It is taking a hammer to squash a fly. Individual solutions for the small handful of homes at risk of flooding should be investigated instead, and assistance provided to the homeowners. This current plan will do nothing to mitigate groundwater flooding of their basements and ponding of water behind the berms; in fact, it’s likely to create and exacerbate those problems. Homeowners have options – landscaping and flood-proofing mitigations can help keep water out. The river and its fish, bird and mammal populations have no such options. I’m not aware of a single environmental group in favour of this project. All of the hard work and money that the QVRRDF and others have invested in our river ecosystem over the decades will have been for nought if this project goes ahead. We have lived adjacent the river for 25-odd years and notice that even ordinary rainfall now causes the river to rise quicker and higher (flash) than it ever did before during such rains. This has happened just since new housing and business developments in marsh land off Kenmount Road went in, and since the former marsh at the bottom of Winter Avenue was covered in new housing and pavement. It is the city’s own misuse of water-permeable land and floodplain that is the far greater cause of any increased local flooding we see on Rennie’s River. Naturally climate change effects will be piled on top of that. We can’t berm our way out of that dilemma. Berms can and do fail, and in any event, merely push the flood problem further downstream and across the river. You say the concrete and earth structure adjacent to Allandale Road is designed to reduce the height of planned downstream berms on Rennie’s River (from a previously proposed 2.2m height at one location!). Even at half that height it is still a ridiculous and destructive proposal, and the citizens won’t stand for it. You read the room tonight in the public meeting as well as I did. In a similar project in Cape Breton, some previously flooded homeowners opted to accept the continuing risk rather than lose their beloved natural areas to berms. Last I heard, the municipality shelved the project. St. John’s should do so as well. link

    This newly proposed flood control “weir” and associated downstream berms and walls, is just not justifiable, monetarily, or environmentally. It is taking a hammer to squash a fly. Individual solutions for the small handful of homes at risk of flooding should be investigated instead, and assistance provided to the homeowners. This current plan will do nothing to mitigate groundwater flooding of their basements and ponding of water behind the berms; in fact, it’s likely to create and exacerbate those problems. Homeowners have options – landscaping and flood-proofing mitigations can help keep water out. The river and its fish, bird and mammal populations have no such options. I’m not aware of a single environmental group in favour of this project. All of the hard work and money that the QVRRDF and others have invested in our river ecosystem over the decades will have been for nought if this project goes ahead. We have lived adjacent the river for 25-odd years and notice that even ordinary rainfall now causes the river to rise quicker and higher (flash) than it ever did before during such rains. This has happened just since new housing and business developments in marsh land off Kenmount Road went in, and since the former marsh at the bottom of Winter Avenue was covered in new housing and pavement. It is the city’s own misuse of water-permeable land and floodplain that is the far greater cause of any increased local flooding we see on Rennie’s River. Naturally climate change effects will be piled on top of that. We can’t berm our way out of that dilemma. Berms can and do fail, and in any event, merely push the flood problem further downstream and across the river. You say the concrete and earth structure adjacent to Allandale Road is designed to reduce the height of planned downstream berms on Rennie’s River (from a previously proposed 2.2m height at one location!). Even at half that height it is still a ridiculous and destructive proposal, and the citizens won’t stand for it. You read the room tonight in the public meeting as well as I did. In a similar project in Cape Breton, some previously flooded homeowners opted to accept the continuing risk rather than lose their beloved natural areas to berms. Last I heard, the municipality shelved the project. St. John’s should do so as well.

    mdm asked over 2 years ago

    Thank you for your comments. They are duly noted.

  • Share Can you show the flood mapping as it is today with no flood control infrastructure in place? on Facebook Share Can you show the flood mapping as it is today with no flood control infrastructure in place? on Twitter Share Can you show the flood mapping as it is today with no flood control infrastructure in place? on Linkedin Email Can you show the flood mapping as it is today with no flood control infrastructure in place? link

    Can you show the flood mapping as it is today with no flood control infrastructure in place?

    David Winter asked over 2 years ago

    This info is in the document library.

  • Share I'm wondering why not have the structure on the Upstream side, as it is part of the Long pond trail. The existing sidewalk there is too narrow for the active traffic there now. My experience is that I commonly meet people walking, biking, with strollers and with dogs and often you have to wait on one side for the people to pass the bridge section before proceeding yourself. In keeping with the active transport promise, shouldn't this structure be able to hold bicycle traffic as well? )Or should the bicycle traffic compete on the 4 lane 50kms hour highway at that bridge.) Thank you, Coleen Dunn on Facebook Share I'm wondering why not have the structure on the Upstream side, as it is part of the Long pond trail. The existing sidewalk there is too narrow for the active traffic there now. My experience is that I commonly meet people walking, biking, with strollers and with dogs and often you have to wait on one side for the people to pass the bridge section before proceeding yourself. In keeping with the active transport promise, shouldn't this structure be able to hold bicycle traffic as well? )Or should the bicycle traffic compete on the 4 lane 50kms hour highway at that bridge.) Thank you, Coleen Dunn on Twitter Share I'm wondering why not have the structure on the Upstream side, as it is part of the Long pond trail. The existing sidewalk there is too narrow for the active traffic there now. My experience is that I commonly meet people walking, biking, with strollers and with dogs and often you have to wait on one side for the people to pass the bridge section before proceeding yourself. In keeping with the active transport promise, shouldn't this structure be able to hold bicycle traffic as well? )Or should the bicycle traffic compete on the 4 lane 50kms hour highway at that bridge.) Thank you, Coleen Dunn on Linkedin Email I'm wondering why not have the structure on the Upstream side, as it is part of the Long pond trail. The existing sidewalk there is too narrow for the active traffic there now. My experience is that I commonly meet people walking, biking, with strollers and with dogs and often you have to wait on one side for the people to pass the bridge section before proceeding yourself. In keeping with the active transport promise, shouldn't this structure be able to hold bicycle traffic as well? )Or should the bicycle traffic compete on the 4 lane 50kms hour highway at that bridge.) Thank you, Coleen Dunn link

    I'm wondering why not have the structure on the Upstream side, as it is part of the Long pond trail. The existing sidewalk there is too narrow for the active traffic there now. My experience is that I commonly meet people walking, biking, with strollers and with dogs and often you have to wait on one side for the people to pass the bridge section before proceeding yourself. In keeping with the active transport promise, shouldn't this structure be able to hold bicycle traffic as well? )Or should the bicycle traffic compete on the 4 lane 50kms hour highway at that bridge.) Thank you, Coleen Dunn

    Coleen10 asked over 2 years ago

    Construction of the flow control structure downstream of Allandale Road is less challenging, and less intrusive to aquatic life in Long Pond, than if the structure was to be built upstream of Allandale Road bridge. A walkway over top of the flow control structure (3m width) is sized to accommodate an active transportation connection if needed in the future.

  • Share Thanks for the reply. I appreciate it. Thanks as well for the photos. Looking at the photos, I just wanted to seek further clarification. You said the finished upper floor is at 56.3 m but in the picture, you labelled the lower door/floor of the facility at 56.3 metres. The upper part is about 2 metres higher than that. So I wanted you to confirm which part of the building is truly at 56.3 m since that's critical to my/our understanding of the current flooding risk and potential effects of this project. When you answered, "The anticipated flood level during the 1:100 AEP climate change + 30% event is 56.0 m" is that with or without the flood control structure in place? If it is without the flood control structure in place, can you please give an estimate with it in place? Thank you. on Facebook Share Thanks for the reply. I appreciate it. Thanks as well for the photos. Looking at the photos, I just wanted to seek further clarification. You said the finished upper floor is at 56.3 m but in the picture, you labelled the lower door/floor of the facility at 56.3 metres. The upper part is about 2 metres higher than that. So I wanted you to confirm which part of the building is truly at 56.3 m since that's critical to my/our understanding of the current flooding risk and potential effects of this project. When you answered, "The anticipated flood level during the 1:100 AEP climate change + 30% event is 56.0 m" is that with or without the flood control structure in place? If it is without the flood control structure in place, can you please give an estimate with it in place? Thank you. on Twitter Share Thanks for the reply. I appreciate it. Thanks as well for the photos. Looking at the photos, I just wanted to seek further clarification. You said the finished upper floor is at 56.3 m but in the picture, you labelled the lower door/floor of the facility at 56.3 metres. The upper part is about 2 metres higher than that. So I wanted you to confirm which part of the building is truly at 56.3 m since that's critical to my/our understanding of the current flooding risk and potential effects of this project. When you answered, "The anticipated flood level during the 1:100 AEP climate change + 30% event is 56.0 m" is that with or without the flood control structure in place? If it is without the flood control structure in place, can you please give an estimate with it in place? Thank you. on Linkedin Email Thanks for the reply. I appreciate it. Thanks as well for the photos. Looking at the photos, I just wanted to seek further clarification. You said the finished upper floor is at 56.3 m but in the picture, you labelled the lower door/floor of the facility at 56.3 metres. The upper part is about 2 metres higher than that. So I wanted you to confirm which part of the building is truly at 56.3 m since that's critical to my/our understanding of the current flooding risk and potential effects of this project. When you answered, "The anticipated flood level during the 1:100 AEP climate change + 30% event is 56.0 m" is that with or without the flood control structure in place? If it is without the flood control structure in place, can you please give an estimate with it in place? Thank you. link

    Thanks for the reply. I appreciate it. Thanks as well for the photos. Looking at the photos, I just wanted to seek further clarification. You said the finished upper floor is at 56.3 m but in the picture, you labelled the lower door/floor of the facility at 56.3 metres. The upper part is about 2 metres higher than that. So I wanted you to confirm which part of the building is truly at 56.3 m since that's critical to my/our understanding of the current flooding risk and potential effects of this project. When you answered, "The anticipated flood level during the 1:100 AEP climate change + 30% event is 56.0 m" is that with or without the flood control structure in place? If it is without the flood control structure in place, can you please give an estimate with it in place? Thank you.

    TALoeffler asked over 2 years ago

    "Looking at the photos, I just wanted to seek further clarification. You said the finished upper floor is at 56.3 m but in the picture, you labelled the lower door/floor of the facility at 56.3 metres."

    It is in fact the upper level of the facility that has a finished floor elevation of 56.3 m. The incorrect photo was labeled. Please see photo below.

    "...is that with or without the flood control structure in place? If it is without the flood control structure in place, can you please give an estimate with it in place?"

    The anticipated flood level during the 1:100 AEP climate change + 30% event is 56.0 m with the flow control structure in place.

  • Share Looking again at the improved flood plain map and trying to understand the difference in what level the lake will be during flood mitigation, it appears that flood level water could advance as high as MUN's Splash facility. Is this correct or have I read the mapping incorrectly? It appears that the shading there goes beyond the current flood plain to through the middle of the building (unless that's not shading-rather the building in satellite view. Can you confirm that the new lake level with flood control in place won't flood that building? on Facebook Share Looking again at the improved flood plain map and trying to understand the difference in what level the lake will be during flood mitigation, it appears that flood level water could advance as high as MUN's Splash facility. Is this correct or have I read the mapping incorrectly? It appears that the shading there goes beyond the current flood plain to through the middle of the building (unless that's not shading-rather the building in satellite view. Can you confirm that the new lake level with flood control in place won't flood that building? on Twitter Share Looking again at the improved flood plain map and trying to understand the difference in what level the lake will be during flood mitigation, it appears that flood level water could advance as high as MUN's Splash facility. Is this correct or have I read the mapping incorrectly? It appears that the shading there goes beyond the current flood plain to through the middle of the building (unless that's not shading-rather the building in satellite view. Can you confirm that the new lake level with flood control in place won't flood that building? on Linkedin Email Looking again at the improved flood plain map and trying to understand the difference in what level the lake will be during flood mitigation, it appears that flood level water could advance as high as MUN's Splash facility. Is this correct or have I read the mapping incorrectly? It appears that the shading there goes beyond the current flood plain to through the middle of the building (unless that's not shading-rather the building in satellite view. Can you confirm that the new lake level with flood control in place won't flood that building? link

    Looking again at the improved flood plain map and trying to understand the difference in what level the lake will be during flood mitigation, it appears that flood level water could advance as high as MUN's Splash facility. Is this correct or have I read the mapping incorrectly? It appears that the shading there goes beyond the current flood plain to through the middle of the building (unless that's not shading-rather the building in satellite view. Can you confirm that the new lake level with flood control in place won't flood that building?

    TALoeffler asked over 2 years ago

    The finished floor of the upper level of the MUN splash facility is at elevation 56.3 m. The anticipated flood level during the 1:100 AEP climate change + 30% event is 56.0 m. Therefore, the upper level of the  splash facility will not be flooded. However, the boat storage area of the splash facility is at a lower elevation and therefore will experience flooding during the design event. The flooding at this lower level is pre-existing and will occur without addition of the flow control structure at Long Pond during a 1:100 AEP climate change + 30% event. Please see the following photos for reference.

     

  • Share Will the structure affect fish migration? If so, how will it be mitigated. on Facebook Share Will the structure affect fish migration? If so, how will it be mitigated. on Twitter Share Will the structure affect fish migration? If so, how will it be mitigated. on Linkedin Email Will the structure affect fish migration? If so, how will it be mitigated. link

    Will the structure affect fish migration? If so, how will it be mitigated.

    Mech_Engineer asked over 2 years ago

    The structure will not affect fish migration as the natural channel will not be altered.

  • Share Sorry, but the maps are very difficult to read. Please, work with colors and the design. Also, you say, "The proposed changes to the Long Pond water level will have a marginal impact on the extent of new trail locations that flood." Could you please make a map with the "new trail locations"? Could you please make an assessment of what exact areas of the trail will be affected? How much are they affected now, and how much will be affected after construction? Honestly said, the difference between existing and post-construction conditions is very little. Then, what is the point of doing it if almost nothing is changing? Could you provide some cost analysis? Thanks! P.S.: Please, make the orientation of .pdf pages horizontal next time if you have horizontally oriented maps. on Facebook Share Sorry, but the maps are very difficult to read. Please, work with colors and the design. Also, you say, "The proposed changes to the Long Pond water level will have a marginal impact on the extent of new trail locations that flood." Could you please make a map with the "new trail locations"? Could you please make an assessment of what exact areas of the trail will be affected? How much are they affected now, and how much will be affected after construction? Honestly said, the difference between existing and post-construction conditions is very little. Then, what is the point of doing it if almost nothing is changing? Could you provide some cost analysis? Thanks! P.S.: Please, make the orientation of .pdf pages horizontal next time if you have horizontally oriented maps. on Twitter Share Sorry, but the maps are very difficult to read. Please, work with colors and the design. Also, you say, "The proposed changes to the Long Pond water level will have a marginal impact on the extent of new trail locations that flood." Could you please make a map with the "new trail locations"? Could you please make an assessment of what exact areas of the trail will be affected? How much are they affected now, and how much will be affected after construction? Honestly said, the difference between existing and post-construction conditions is very little. Then, what is the point of doing it if almost nothing is changing? Could you provide some cost analysis? Thanks! P.S.: Please, make the orientation of .pdf pages horizontal next time if you have horizontally oriented maps. on Linkedin Email Sorry, but the maps are very difficult to read. Please, work with colors and the design. Also, you say, "The proposed changes to the Long Pond water level will have a marginal impact on the extent of new trail locations that flood." Could you please make a map with the "new trail locations"? Could you please make an assessment of what exact areas of the trail will be affected? How much are they affected now, and how much will be affected after construction? Honestly said, the difference between existing and post-construction conditions is very little. Then, what is the point of doing it if almost nothing is changing? Could you provide some cost analysis? Thanks! P.S.: Please, make the orientation of .pdf pages horizontal next time if you have horizontally oriented maps. link

    Sorry, but the maps are very difficult to read. Please, work with colors and the design. Also, you say, "The proposed changes to the Long Pond water level will have a marginal impact on the extent of new trail locations that flood." Could you please make a map with the "new trail locations"? Could you please make an assessment of what exact areas of the trail will be affected? How much are they affected now, and how much will be affected after construction? Honestly said, the difference between existing and post-construction conditions is very little. Then, what is the point of doing it if almost nothing is changing? Could you provide some cost analysis? Thanks! P.S.: Please, make the orientation of .pdf pages horizontal next time if you have horizontally oriented maps.

    Maria_Yulmetova asked over 2 years ago

    The orientation has been changed. There are no new trails to be constructed as a part of this project.  There will however be new areas that will flood due to the higher water elevation.

    The length of the trail around Long Pond is approximately 2,905m.  The table below summaries the existing trail length and new trail length to be inundated during the three design storms.


    Flow Event

    Length of Long Pond Trail Flooding (m)

    Existing Conditions

    Post Flow Control Structure Construction

    1:20 AEP CC

    670

    760

    1:100 AEP CC

    935

    1,030

    1:100 AEP CC + 30%

    1,110

    1,395


    The flow control structure at Long Pond does not eliminate the need for flood protection measures along Rennies River downstream of Long Pond. The major benefit of the flow control structure is that the peak flows downstream of Long Pond will be reduced, resulting in reduced costs associated with the implementation of flood control options at locations downstream.

  • Share What steps are being taken to design - or re-design - upstream development to limit the pressure of future flooding? Is consideration being given to retaining existing wet lands and native tree cover, or to replanting areas already damaged by development? on Facebook Share What steps are being taken to design - or re-design - upstream development to limit the pressure of future flooding? Is consideration being given to retaining existing wet lands and native tree cover, or to replanting areas already damaged by development? on Twitter Share What steps are being taken to design - or re-design - upstream development to limit the pressure of future flooding? Is consideration being given to retaining existing wet lands and native tree cover, or to replanting areas already damaged by development? on Linkedin Email What steps are being taken to design - or re-design - upstream development to limit the pressure of future flooding? Is consideration being given to retaining existing wet lands and native tree cover, or to replanting areas already damaged by development? link

    What steps are being taken to design - or re-design - upstream development to limit the pressure of future flooding? Is consideration being given to retaining existing wet lands and native tree cover, or to replanting areas already damaged by development?

    p.houlden asked over 2 years ago

    The proposed flood mitigation works are designed given consideration to the upstream development limits and zoning.  The existing wetlands are protected by zoning and wetland overlays.  The City requires new development to incorporate stormwater management measures as per its Stormwater Detention Policy. The policy states that the post-development runoff rates cannot exceed the pre-development runoff rates; this negates the downstream impact of a development. Developers can achieve this by storage or by retention methods such as bioswales, rain gardens, etc.

  • Share Looks like a nicer way for pedestrians and bikers to cross the water... other than the existing very narrow sidewalk on the very busy bridge! on Facebook Share Looks like a nicer way for pedestrians and bikers to cross the water... other than the existing very narrow sidewalk on the very busy bridge! on Twitter Share Looks like a nicer way for pedestrians and bikers to cross the water... other than the existing very narrow sidewalk on the very busy bridge! on Linkedin Email Looks like a nicer way for pedestrians and bikers to cross the water... other than the existing very narrow sidewalk on the very busy bridge! link

    Looks like a nicer way for pedestrians and bikers to cross the water... other than the existing very narrow sidewalk on the very busy bridge!

    BES asked over 2 years ago

    Thank you for the feedback.

Page last updated: 30 Jan 2024, 04:20 PM