E.T. Seton Bridge Project Status

E.T. Seton Bridge Project.

Map Legend

Green: open trails (not plowed)

Red: wooden ramp removed, access extremely limited

Black: approximate placement of temporary fences

Blue: informal detour (use at own risk)

I visited the bridge replacement project site at the south end of E.T. Seton Park. It looks like the construction company has abandoned the site for the winter. Some fences are still up but all is not lost. The bridge across the railway tracks is still usable and if you are coming from Don Mills and Overlea (Flemingdon Park) you can still access the bridge via a narrow set of stairs. However the access ramp from E.T. Seton has been removed and is impassible except for the most intrepid of hikers. Getting a bike through here is next to impossible. There is an alternative informal path but it involves crossing the CN tracks and I can't recommend that but it appears that some people are using it. So despite the signs and fencing there is currently limited access. 

I heard through councillor Jaye Robinson's office that a metal ramp will be installed late February, early March. It was my understanding that the Bailey bridge crossing the tracks would also be replaced. There is no word on when this will happen.

 

Project sign. The recommended detours are laughable at best. I doubt anybody bothers with them.

The bridge is still up. The former wide wooden stairs at the north end have been replaced by a set of narrow stone stairs. Not very bicycle friendly.

The old wooden ramp has been removed. Cement foundations have been put in place in preparation for a new ramp which has yet to be installed.

A look at the bridge with some interesting graffiti/art on the right.

Milkman's Lane Closed

Just north of Castlefrank Subway station is a secluded but well used path that provides a way down into the Don Valley. From the bottom of this path you can access the Don Valley Brick Works and the Belt Line path. How Milkman's Lane got its start is something of a mystery but local legend has it that when milk was still delivered to homes in the morning, this path provided a back entrance for milk carts for the tony neighbourhood of Rosedale.

Regardless of its origins, this well used access path is under severe stress. Whenever it rains, water sluices down the middle of the path creating deep furrows. This creates a hazard for both cyclists and pedestrians as they try to navigate the path.

This fall the city has decided to do some repair work. A new path will be constructed. When completed, the path will be raised in the middle with drainage ditches on the side to collect runoff. Cedar rail fencing will delineate the path but also limit dogs to the path to protect the fragile forest slope on either side of the path. In addition, informal paths that lace the nearby slopes will be closed off to allow for natural forest restoration.

The path is set to reopen, barring unforeseen delays due to weather or site problems, by mid-December 2011. For further information on this project see this page on the city's website.


Milkman's Lane


Rain runoff is creating deep gullies in path

Pottery Road to Open by November 30

Unstable retaining wall on Pottery Road

Word has it that Pottery Road will be reopened for road traffic by November 30. The problem was due to an unstable retaining wall that was due to the fact that they cut away too much of the slope behind it which led to the possibility of the slope collapsing. The retaining wall as constructed would then have failed.

A engineering solution has been chosen. I don't whether it is a strengthened wall or some sort of slope stabilization (or both) but it should be complete in a month. Work on the rest of the road is nearly complete. In the meantime, the pedestrian/bike path is still usable. I advise caution in its use as construction activities are still on-going.

New Wetland in Taylor Creek Park

New wetland under construction

The Taylor Creek Park ravine is blessed with several areas of natural water discharge which has created marshy areas at the bottom of both sides of the ravines. These manifest themselves as cattail covered wet areas that are not too interesting from either an aesthetic or ecological perspective. One step up from a cattail fen is an open water pond. Ponds have a much greater diversity potential allowing habitat for mammals, birds, and amphibians. Since this ravine has been highly modified by human activities over the past 100 years, all of the natural ponds were filled in. From a natural environment perspective it makes sense to improve habitat by recreating them.

This has recently occurred just west of the O'Connor Bridge. A new wetland has been excavated in one of the cattail fens. The area is covered in natural water that flows into the nearby Taylor-Massey Creek. It doesn't look like much now but by next year this time it should look more like the new wetland further up the valley.


Mallard duck checking out the new pond

Pottery Road Open (for Bikes)

Pottery Road closed at Broadview Avenue

A recent article in the Toronto Star highlighted the recent makeover of Pottery Road which apparently isn't going all that well. Apparently the slope behind a new retaining wall is unstable and they can't guarantee that it won't collapse so they've put the reopening on hold until they figure it out.

While the article said that car traffic is disrupted, they neglected to mention that the new bicycle/walking path is complete and fully available for use. A sign at the top of the hill says the path is closed but you can safely ignore it. The path which is separated from the road by jersey barriers is about 2m wide and fully paved. Caution is still warranted as the railing on the hill side hasn't been fully installed.

So too bad about cars but cyclists and hikers can rejoice!


Sidewalk sign says closed, use other sidewalk but there is no other sidewalk (hint: ignore sign)


Looking down the hill - brand new pavement


Looking up the hill. Retaining wall in question on the left


Wide path beside road. Todmorden Mills on the right, Fantasy Farm on the left


Expanded path underneath the DVP


New connection to Lower Don trail


Intersection at Bayview now includes a pedestrian crosswalk. The other side leads to an narrow paved median which can be used (with caution) to access the Brick Works.


Another view of the intersection at Bayview

Earl Bales Stormwater Pond

Site of stormwater pond (click to enlarge)


Schematic of proposed pond in the valley. The light green area at the top right is the golf course.


A couple of schematic drawings of the pond. A path on a causeway will lead to a lookout and interpretive area.

This summer a major construction project will take place on the West Don at the southeast corner of Earl Bales Park. This project which is the culmination of several years of planning will create a stormwater management pond that will capture storm water before it enters the Don River. The pond location is at the base of two creeks, Earl Bales Creek and Dehavilland Creek. Both creeks used to run west towards the Downsview Park area but are now mostly buried in storm sewers. The remnants of their ravines are now confined to the park east of Bathurst Ave. Both of these ravines are severely degraded due to flash flooding from storm water.


Outfall from former DeHavilland Creek. This will be diverted into the new pond

The purpose of the pond is to capture the stormwater before it enters the river. Stormwater and its resultant pollution is the single most important environmental problem affecting the Don River today. When rain falls on a watershed, the water is either absorbed by trees and other vegetation or percolates into the ground. The water eventually enters the river at a steady rate. However, in an urban watershed like the Don, ground cover is dominated by roads and buildings. Water falling on these areas is quickly diverted into storm sewers where it floods into the river. These flash flood events tend to scour out the creeks and rivers. The water picks up dirt and mud and other things. All the suspended material including whatever pollutants from the roads (road salt, oil, grease, etc.) is washed into the river which severely degrades available habitat for fish and other water dwelling organisms. The Don River used to be a healthy river teeming with fish but not any longer. The "Muddy Don" got its nickname because we made it that way.

This stormwater pond is just one small aspect of the slow process of river restoration. Its main purpose will be to stop the stormwater from quickly entering the river. The water will be stored here until the suspended material has had a chance to settle to the bottom of the pond. It is estimated that 20% of the 35,000 cubic metres of silt annually dredged from the mouth of the Don River comes from the Earl Bales park area.



The pond site looking southwest toward the foot of Westgate Blvd.


Looking northeast

The pond will also act as a reservoir for two nearby water uses. The Don Valley Golf Course currently draws water from the river for its grass watering needs. The Earl Bales Ski Hill also does the same for snow making during the winter. After the pond is built the water will be taken from the pond instead.

The pond will provide limited habitat for some wildlife. However it will not be a fully functioning wetland since it will need to be periodically dredged which will cause major disturbances in the pond. Yet overall, the effect will be an improvement in the overall health of the river and the Don Valley. I hope to visit the site a couple of times this year to document progress on this project.


Notice of construction at entrance to the valley at Westgate Blvd.

Sewer Project Blocks Taylor Creek Road

Map of construction area

There is some unusual construction going on at the Forks of the Don. The road that leads to the western Taylor Creek Park parking lot is closed for the month of April. The reason for this is that the road underneath the Don Valley Parkway needs to be lowered to allow for some heavy machinery to access the construction site where they will dig a tunnel for a sewer project.

This particular project is meant to create a bypass around a damaged sewer pipe 60m below the ground that was discovered to be cracked. This pipe carries the sewage for 1/3 of Toronto's residents. If the crack becomes critical and the sewer fails, all the sewage would be diverted into the Don River - a manmade disaster for the Don and the harbour where the polluted water would end up. So repairing the sewer is a critical task. The project involves boring a bypass tunnel around the cracked section. Once the bypass is built the sewage can be rerouted and the damaged section can be drained for inspection. It is hoped that when it is dry it can be repaired.

This is part of a larger project to twin the sewer pipe because right now there is no alternative to the single pipe in use now. It was built in 1958 and it is close to capacity. The entire project (still unfunded) is expected to take another 5-10 years to complete.


Looking east underneath DVP bridge. The Elevated Wetland solar panel tower is on the left.


Looking west underneath bridge. The road has been lowered by about 1.5m.


Construction staging area at south end of parking lot

Construction at Todmorden Mills

Road and parking lot construction at Todmorden Mills

There is quite a bit of activity at Todmorden Mills these days. Construction has started on a new road access to the rear parking lot. This has been deemed necessary because the old bridge that was used to get to the parking lot has been condemned. The bridge was built in 1931 and used to cross the Don River when it ran through this part of the valley. When the Don Valley Parkway was built this section of the Don River was cut off and the bridge no longer served a major purpose. It has gone down hill ever since and now stands cut off and disused.

The new access road is being built next to the DVP embankment. Steps have been taken to protect trees near the construction site but other sizable trees were taken down that were in the way. I suppose it will look a lot better when it is finished. It's too bad they couldn't do anything with the old bridge since it is a part of the Don Valley's heritage and many of those are disappearing.


Tree protection fencing erected around large tree.


What the sign on the fence says


Straw bales have been placed to trap runoff from the parking lot during construction


Temporary catchment pond for water running from the pond and ditches.


The old bridge. On its way out?

Wicking Water

Just south of the Queen Street bridge some odd looking construction is occurring. There appears to be a forest of silver ribbons poking out of the ground. What are they doing? This technique is called wicking and it is used to remove moisture from the ground.

This area is the northwest corner of the future Don River Park and the western portion is being anchored by what is officially known as a "flood protection landform". This is a kind of levee or berm and is meant to protect the West Don Lands from serious flooding on the order of a Hurricane Hazel size storm. The construction of the berm requires that a large amount of earth be piled in one place. Before that can be done, the ground beneath it must be dried out and compacted. The easiest way to dry out the ground is to insert these silver coloured plastic strips into the ground. Using capillary action, the water in the soil travels to the surface where it evaporates into the air. Once the soil is dried out sufficiently then the new soil can be placed on top. Dry soil compacts easier and has less chance of shifting or moving later on, which is something you don't want to happen for a device that is meant to hold back large amounts of water.


Ribbon forest

Silver coloured wicking strips

The berm is expected to be completed sometime this fall. Once complete, construction of the park and the new neighbourhood to the west can commence.

Coxwell Sanitary Sewer Update

Sewer grate c1959. Located near the mouth of Taylor-Massey Creek and demarcates the merging of 3 sewer mains into the Coxwell Sanitary Sewer. Warning: the odour from this access tunnel is very strong and shouldn't be approached by those with a weak stomach!

After a flurry of fairly high profile news items earlier this year, the story of the Coxwell sanitary sewer problems has fallen off the radar. This does not mean that work has slowed down. Far from it. Toronto Water has been very busy with a wide range of activities from setting up monitoring devices to developing contingency plans in the event of a failure of the sewer to plans that will lead to eventual repair of the sewer.

There are two foreseeable outcomes. The first is that the sewer fails in the near future which would have dire consequences for the Don River. The second (and much more likely) course of events is that Toronto Water successfully completes repairs on the sewer main and everything works out OK.

Let me start with the bad news scenario. Since the damage to the sewer was discovered, the city has taken steps to make plans in the event of a failure. No one knows when the damage to the sewer occurred or how extensive the damage is. Nor are they sure how long the sewer will last. It could fail today or it could last another 60 years. Given this situation city staff have to plan for the worst. In the event of a failure the plan is to divert the sewage into the Don River. The flow in the pipe is about 6 m³/s or about 4 times the normal flow of the Don River. The effluent would flow all the way down the river to the harbour. The plan calls for the effluent to be treated in the Keating Channel which would remove the worst of the flow but the remaining water would be highly polluted.

The effect of this would be catastrophic. All oxygen would be removed from the river and everything now living in the river would die. Water in the harbour would be highly anaerobic and E. coli levels would be through the ceiling. The combined sewer and river flow would be contained in the river channel but a rainstorm during this flow would likely cause the river to overflow the banks causing sewage laden waters to flood the lower Don Valley. No matter how you look at it, a collapse would be a major environmental disaster.

In the meantime work is underway to build a bypass around the damaged pipe. Two options are being evaluated, a temporary bypass and a permanent bypass. The temporary bypass would involve constructing one or more pipes above ground. The pipes would extend from the bottom of the valley near the mouth of Taylor-Massey Creek up to the corner of Coxwell and O'Connor. A shaft would be dug at that corner back down to the pipe. The sewer contents would be pumped up the side of the valley and back down the shaft to reenter the pipe downstream from the damaged section.

The permanent bypass solution would tunnel underground roughly parallel to the existing pipe and create a diversion around the damaged section. Either solution would allow engineers to enter the existing pipe to initiate repairs. The timeline for both options is 9-12 months and would cost about $30 million. The temporary would take a little less time but would be more damaging to the natural landscape of the valley. Also the temporary solution allows for only one oppotunity for repairs. Since the cost for both options is roughly similar and the timelines are not that far apart, city staff are leaning towards the permanent solution.

It is good to know that the city is taking the situation very seriously and I am confident that the plans in place are sufficient to produce a positive outcome. I rate the possibility of failure of the sewer to be very low. I am reasonably certain that by the end of this project we will again have a working sewer and the Don River will continue to flow without the added complication of input from the Coxwell sewer.

For anyone who wants additional information on this subject, you can view Toronto Water's slideshow presentation to the Public Works Committee from January 2009.

Greenwashing Parking Lots

Parking lot newly resurfaced. Asphalt surface allows for zero infiltration of rain.

Last year the city announced with some fanfare the creation of green standards for parking lots. These standards give guidelines for building parking lots that will reduce their impact on the environment. Current construction methods are simple and cheap but add to a host of environmental problems. Black asphalt bakes in the sun. The cumulative effect of all the parking lots in the city along with other urban structures increases the urban heat island effect. When rain hits an asphalt surface, it heats up and quickly runs off into the nearest sewer. This warm water runoff in downtown Toronto is quickly routed toward watercourses such as the Don River. The flush of warm water along with all the grit, oil, and other pollutants it picks up along the way is the major cause of habitat degradation in our river systems.

The green standards seek to reduce these effects with a number of design changes. Foremost is the inclusion of permeable paving surfaces. This type of surface allows for infiltration of rain water into the underlying soil. Another consideration is to break up the expanse of asphalt by planting trees within the parking lot. Additionally swales can be added to capture runoff from the surface before it hits the sewers.

All this sounds great but it has apparently fallen on deaf ears when it comes to actually applying these methods. This past winter a parking lot in Stan Wadlow Park at the edge of Taylor-Massey Creek was resurfaced. The parking lot was completely resurfaced with asphalt. Only one small island around a hydro pole was left for planting. On the south side of the parking lot a swale was dug but this will have next to no effect because the asphalt surface has been graded to slope away from it toward the middle where there are two storm drains. This means that less than 1% of the total parking lot runoff will flow into the swale.


Storm drains in centre of parking area. Asphalt is sloped down toward them which collects all the runoff.


Swales are meant to trap runoff but this one will capture none. Curb stones prevent most runoff reaching the swale and the asphalt is sloped away from it.

So, it seems that on the surface the city has tried to apply the new standards but the application here is paper thin. The city needs to set a higher standard when redesigning its own parking lots. How do they expect private parking lot builders to do better when they fail so miserably?


One small area left open. Since it's next to a hydro pole there won't be any shade trees, just decorative shrubs.

Don Path Reroute

Bank erosion

Just south of the forks of the Don, the river runs through a relatively deserted section of the valley. Apart from a hydro corridor and the Leaside bridge there is not much to see other than the path and the river. This actually makes it a good place to view the river because there is nothing else to distract your attention. The path parallels the river and at times is right beside it. Unfortunately this causes problems when the river decides to do something like move its banks.


Erosion starting to cut into path

Last summer the river started cutting into the bank near a willow tree which was anchoring the bank. This cut became enlarged during a heavy rainstorm. The city put up a fence but it was obvious that the path would start to collapse into the river.


New path is to the left, the old path ran along the fencing. The asphalt has already been removed.

So early this spring a crew came in to close down the path next to the river and move it about 10m away. The detour is very smooth riding but you can't see the river as much in this section.



I took a short video while riding along the new section. Since the audio is not very interesting (wind and traffic noises) I found some 'riding' music and used that instead. The track is from SomaFM, an internet radio station that streams a variety of techno music. This track is from the stream called Groove Salad, one of my favourites.

Another Sewer For the Don

New sewer outlet near mouth of East Don

Travelling in the lower Don is tough in early spring. The paths are lined with frozen mush so it is hard to walk or bike. But I managed anyways yesterday given some unusual mild weather. My goal was to see for myself some recent work being done in the valley. And I was not disappointed. Just up from the forks of the Don near the Elevated Wetlands, there is a small site which has seen some furious construction activity. Toronto Water has built a new sewer outlet which will empty out directly into the Don River.

It is of course their fervent hope that it will not be used but recent discoveries in the trunk sewer beneath the valley led to this construction. As reported in the news early January, cracks were discovered in a Coxwell Trunk sewer pipe that services nearly a million Toronto residents. The city does not know the full extent of the damage nor do they know if or when the pipe will fail. But being sensible people, they need to plan for the worst case. This worst case scenario would mean that the sewage water flowing through the pipe would need to flow somewhere and right now that means directly into the Don River.

Other contingency plans are also in the works. The main plan is to build a diversion pipe around the damaged pipe so that the flow can be directed into a parallel pipe around the damaged section. This will cost between 7-30 million dollars and take 12-18 months to build. In the event that something occurs in the interim there are a couple of emergency options:

1. Pictured above. Divert the flow into the Don River. Allow it to flow down to the harbour where a PVC curtain will be anchored stopping the effluent from reaching the lake. The water will be pumped out and directed toward Ashbridges Bay Treatment Plant.
2. Direct the flow to the North Toronto Treatment Plant. This plant now services parts of Leaside and the Yonge Eglinton area. There is an overflow pipe from this plant to the damaged trunk sewer. It would be possible to reverse the flow in this pipe back to the treatment plant. The NTTP is way too small to handle the complete flow from the Coxwell Trunk Sewer but could do primary treatment before sending into the river
3. Build a temporary pipe above ground around the damaged section. This could be built along the Don Valley or above ground on Coxwell Avenue. This one doesn't sound very palatable and would cause major disruptions in traffic and pedestrian flow in this neighbourhood.

Toronto Water is also doing due diligence with the rest of the system and so far they have investigated pipes in downtown Toronto and the rest of the Don. They are happy to report that no other major problems have been found, although they still have to investigate systems in Scarborough and Etobicoke.

Additional construction will start later this spring when they start to bore a hole underneath the valley for the diversion pipe. It is is hoped that this can be done with a mininum of disruption to the natural environment. Let's all cross our fingers and hope that this is a successful project.


Toronto Water built a temporary bridge across mouth of Taylor-Massey Creek


Barbara Crescent is an unassuming street in East York. The damaged sewer pipe is directly beneath this line of markings on the street

Ominous street markings indicate what lies beneath