RAIN CITY STRATEGY - vancouver.cavancouver.ca/files/cov/rain-city-engagement-boards-20180308.pdf · Vancouver’s water ... Most of the pollution in urban waterways is caused by our

vancouver.ca/raincitystrategy #RainCityStrategyGreen Infrastructure Implementation

March 2018

Welcome! The City of Vancouver is in the process of developing a Rain City Strategy. We envision a city where rainwater is embraced as a valued resource for our communities and natural ecosystems.

We invite you to learn about how we are developing this strategy. Chat with us and find out what you can do to improve and protect Vancouver’s water quality and help our city be more resilient to climate change. Please share your thoughts and ideas as we embark on this transformational project!

Project Timeline

Engagement Timeline

RAIN CITYSTRATEGY

Vancouver Citywide Integrated Rainwater Management Plan

Rain City Strategy

Implementation

Phase 1 Phase 2

Phase 2

Phase 3

Internal Engagement

with City Departments

Consultation with an Expert

Panel

Public Engagement

Industry Engagement

Writing the Rain City Strategy

Report

Rain City Strategy presented to

Council

2018 onwards2017- 20182016

June/July 2018

Ongoing Ongoing Ongoing UpcomingComplete Upcoming

Image: Wendy de Hoog

2RAIN CITY STRATEGY


March 2018

Why Manage Rainwater?

Most of the pollution in urban waterways is caused by our day-to-day activities in the city. For instance, every time it rains, urban rainwater runoff picks up street contaminants that can harm local ecosystems and have negative impacts on human health and recreation opportunities. Urban rainwater contaminants include:

WinterWe can expect warmer winters, with a 58% decrease in snowpack. Snowpack allows us to recharge our drinking water reservoirs after the rainy season ends.

Resilience

Livability

SpringOur springs will get warmer, with earlier snowmelt, a 72% decrease in frost days, and a 20% increase in April showers.

Sea Level RiseWe are likely to see 0.5m of sea level rise by 2050, which contributes to increased flood risk.

We need to be able to address changes to our climate in every season.

Water Quality

Every time you use the brakes on your car, small amounts of copper are released onto the road and taken up by rainwater runoff.

Did you know...?

With the amount of rain we get here in Vancouver, it may seem like we could never run out of water. However, with our dry summers, increasing population, and changing climate conditions, we are less water secure than we appear. By the year 2050:

93% of Vancouver residents live within a 5 minute walk of a park or greenspace.

Increased access to green space has been shown to counter many of the negative health impacts of city life. It has been shown to improve anxiety, depression, heart disease, and obesity, the risks of which are all higher for people living in urban areas. The benefits of green space are seen for people of all ages, increasing the quality of life for all urban residents throughout their lives.

Many rainwater management strategies proposed by the Rain City Strategy include additional trees, gardens, and other green space. This will help us achieve our many livability goals, and enhance livability for other species by providing habitat for local wildlife.

• 9% decrease in high blood pressure rates from a half hour walk in nature

• Half an hour in nature reduces the risk of depression by 7%

• Lower cortisol levels from green space views

• Decrease in ADD & ADHD symptoms for children with access to nature near the home

• 12% lower mortality rate for people living in greener areas

• Time in nature for pregnant women increases healthy birth weights of babies

Heavy metals

Hydrocarbons

Sanitary waste

Fertilizers

Pesticides

SummerOur summers are likely to be hotter, with 20% less rain, more frequent heat waves, and twice as many days above 25°C. This means more water restrictions and thirsty plants.

AutumnThe autumn months are likely to be wetter, with heavy rain events that are 35% more intense, and 21% more rain on the wettest days. This increases the risk of flooding.

including zinc, lead, copper, cadmium and mercury, in great enough concentrations can be toxic to aquatic life, harming important local species like salmon. They are often found in rainwater runoff.

like gasoline, lubricants, and oils from vehicles are picked up off of roads by rainwater, and carried into our local waterways.

reaches our waterways primarily through combined sewer overflows (CSOs) and can introduce pathogens, such as E. coli, and pharmaceuticals into our water and marine food sources.

add extra nutrients to the water, which use up all the oxygen as it decomposes.

remain in the food chain for a long time and can have negative effects on marine life.

Icons: The Noun Project

3RAIN CITY STRATEGY


March 2018

What’s up with the Water Cycle?

Vancouver is famous for its rain. On average, it rains over 160 days and 1.2 - 1.6 metres a year, and the rain has become part of our identity as a city. The rain is also what enables the incredible natural ecosystems of the Vancouver area, supporting the lush, temperate rainforests of the Pacific coast.

Around 70% of our rainfall volume arrives as light showers, and another 20% as larger storms. The last 10% of our annual rainfall arrives as extreme storms, which are predicted to increase in intensity due to climate change. In the summer, we have a different situation- our summers are dry, and predicted to become even more so as the climate changes. Our rainwater management strategies need to take this seasonality and predicted increase in water volume into account.

Vancouver’s sewer and drainage system provides essential public health and safety services. Over the last 120 years, a complex system of pipes and pumps has been constructed to move rainwater and sewage away from buildings to treatment or discharge in the waters surrounding Vancouver.

About half of the city is served by combined sewers, which is where one pipe carries both rainwater and sanitary sewage. During dry conditions this mixed combined sewage is sent to a treatment plant. When it rains, the combined sewers fill up and overflow a mix of rainwater and sanitary sewage into the waters surrounding Vancouver. This is called a combined sewer overflow (CSO). The rest of the city is served by separated sewers, where sanitary is sent to treatment and the rainwater is discharged directly into our waterways. The City is obligated to eliminate CSOs by 2050.

Vancouver’s drinking water comes from three reservoirs: the Capilano and Seymour Reservoirs in the North Shore mountains, and the Coquitlam reservoir, located just north of the City of Coquitlam. The water in the reservoirs comes primarily from rain and snowpack, which is collected by various rivers and streams into the reservoir lakes. These reservoirs are managed by Metro Vancouver.

The water is treated, and then sent through pipes that pass from the North Shore and over from Coquitlam, providing drinking water to 2.5 million residents of the Metro Vancouver area. Because we rely on rainwater and snow for our drinking water supply, changes to the climate could have significant impacts on our water supply.

Our Rain Sewer System Drinking Water

The water cycle is the journey water takes around the world. When it rains, some of the rainwater is absorbed by plants. Some infiltrates through the soil into groundwater. Some flows along the surface and joins streams, rivers, lakes, and oceans. Eventually, the water evaporates becoming a gas, and gathering in the sky to form clouds, which bring rain, and begin the cycle again.

In urban areas, this cycle is changed. There are fewer plants or soils to absorb the water, and as the water flows along paved city surfaces, instead of collecting in streams, it collects in pipes. It is then conveyed underground into receiving waters, like English Bay, the Fraser River, and Burrard Inlet.

The Water Cycle

In Vancouver, it rains an average of 1200 to 1600 mm a year. That’s the equivalent

of 46,000 Olympic swimming pools!

We depend on rain for our drinking water.

Vancouver’s sewers are complex and evolving.

Our winters are wet, but our summers are dry.

Image: iStock, Icons: The Noun Project

4RAIN CITY STRATEGY


March 2018

Watersheds of Vancouver

A watershed is an area of land where surface water and rain collects, often a stream or a river. Watersheds are usually determined by topography, or the shape of the land, as water flows downhill. In urban areas, streams have often been paved over or put into pipes underground, and water is collected into catch basins. In Vancouver, our 19 watersheds run mostly through our pipes, and drain into False Creek, English Bay, the Fraser River, and Burrard Inlet.

The Rain City Strategy will include recommendations for how to move forward in the implementation phases of our rainwater management plan. One of these recommendations will be to plan and coordinate green infrastructure projects on a watershed scale. Each of the 19 watersheds has unique characteristics and neighbourhood dynamics. Planning by watershed allows us to address these unique needs, while also considering the downstream and cumulative impacts of each project.

Downstream impacts can be hugely important, but aren’t always intuitive, especially in urban watersheds where much of the water moves around underground. Because of the shape and size of a watershed, water quality problems or flooding in one place could be caused by a failure to manage rainwater fairly far away. Planning by watershed means we can take a wider view of our rainwater flow patterns, and address issues at their source. We can also work to ensure water is filtered and cleaned before it reaches the bottom of the watershed, and flows into our local receiving waters.

Before Vancouver’s development, many streams flowed across the peninsula. Over the 19th and early 20th centuries, Vancouver’s development advanced with little regard for the watersheds and watercourses that dissected it. Most streams were culverted, and ravines were filled for development. The map above shows where our lost streams used to be.

Today, only two watersheds have retained surface streams: Still Creek and Musqueam Creek. Plans are being developed to daylight more streams, returning them to the surface to manage rainwater runoff and provide habitat and park space. However, most of the area of Vancouver has fully developed urban conditions where all the drainage is piped, so opportunities for daylighting are limited.

Planning by Watershed

What is a watershed?

Historic Streams

Watersheds

Lost historicstreams

Parks

19

50+

264

We can customize strategies to fit the needs of each watershed.

Vancouver’s watersheds are now almost entirely underground.

False Creek Bridge, 1893 (Present day Main Street, looking north toward Mt. Pleasant)

Diagram of a watershed

Watersheds

Parks

Historic Stream

Sketch: Yette Gram, Photo: VPL Archives

5RAIN CITY STRATEGY


March 2018

Regulatory Requirements

Supporting CityStrategies

Vancouver Flood Strategy (2013)Urban Forest Strategy (2014)Healthy City Strategy (2014)Biodiversity Strategy (2016)Complete Streets Policy (2017) … and many more!

Green BuildingsPolicy for Rezonings

Rezoning Policy for Sustainable Large

DevelopmentsThis bylaw requires that buildings applying for rezoning must, among other things, manage the site’s rainfall using integrated rainwater management and green infrastructure, as described in the city-wide IRMP.

This policy applies to rezoning applications for large development sites, and requires a defined rainwater management plan.

Vancouver Citywide IntegratedRainwater Management Plan (IRMP)

This management plan is mandated by the Metro Vancouver ILWRMP, and primarily targets the quality of water being released into the environment through storm drains and other city pipes. This IRMP also led to the creation of the Green Infrastructure team, who are responsible for developing the Rain City Strategy as the next step of implementation.

The target of the Rain City Strategy is to capture and clean 90% of the rainwater that falls in Vancouver.

RAIN CITY Strategy

Metro Vancouver Integrated Liquid Waste and Resource Management Plan (ILWRMP)Federal and Provincial government water quality guidelines led to thedevelopment of this regional implementation strategy, which sets newregulations and requirements around water quality management.

The City’s plan to be the most sustainable city in the world requires anintegrated rainwater management plan, and supports efforts to reducewater consumption. The Rain City Strategy will help meet theseGreenest City goals.

Greenest City Action Plan

This strategy aims to prepare Vancouver for the realities of a changingclimate. Adaptation actions include continuing work on rainwatermanagement, water conservation actions, and flood-proofing policies;all of which are part of the Rain City Strategy.

Climate Change Adaptation Strategy

2016

Updated 2016

2012

2010

Climate Change Icon: The Noun Project

6RAIN CITY STRATEGY


March 2018

Developing Vancouver’s Plan

Embracing Vancouver’s rainwater as a valued resource for our communities and natural ecosystems.

Goals

Resilience Water Quality

Livability

Objectives

Remove pollutants from water and airGreen Infrastructure removes pollutants by harnessing natural processes and restoring ecosystems in the city. Plants and soil work together to filter pollutants, sequester carbon, and clean stormwater.

Harvest and reuse waterRainwater is a resource which will be increasingly concentrated in the winter months. Harvesting and reusing rainwater reduces our demand for potable water, and allows other types of water to be used for non-potable purposes, like irrigation.

Increase managed impermeable areaVancouver is a highly built-up urban area filled with hardscape. Increasing the management of impermeable area allows for more integrated rainwater management, that will help capture and clean urban rainwater runoff.

Reduce volume of water entering pipesGreen Infrastructure practices slow down the movement of water, allowing more to infiltrate into the ground and evapotranspire into the atmosphere.This results

in reduced water volume entering our stormwater system.

Increase total green areaThe city’s parks and green spaces provide a host of environmental, physical, and mental health benefits.

Mitigate urban heat island effectUrban areas are significantly warmer than surrounding areas. Green

infrastructure solutions help provide localized cooling by increasing the tree canopy and reducing hardscape, thereby mitigating this effect.

Increase Vancouver’s resilience through sustainable water

management

Improve and protect Vancouver’s water

quality

Enhance Vancouver’s livability by improving

urban and natural ecosystems

Icons: The Noun Project

7RAIN CITY STRATEGY


March 2018

Green Infrastructure

Green infrastructure is an approach to water management that protects, restores, or mimics the natural water cycle. It uses soils, plants, trees, and built structures such as green roofs, swales, and rain gardens, to capture, store, and clean rainwater before returning it to our waterways and atmosphere. It increases the city’s resilience to climate change, and supports neighbourhood livability and biodiversity. Green infrastructure delivers several co-benefits in addition to simply managing our rainwater.

What is Green Infrastructure?

Benefits

Clean Air & WaterClimate Change Adaptation

Biodiversity &Habitat

Infrastructure CostSavings

Community Building

Physical & Mental Health

Due to sea level rise and an increase in extreme rain events, climate change will lead to greater risks of flooding. Green infrastructure approaches to rainwater management help reduce and control flooding. They also provide important cooling benefits by increasing green space.

Increased green space and beautification of public space with green infrastructure can encourage people to spend more time outdoors in their communities, providing opportunities for social interaction and community building.

Green infrastructure features like constructed wetlands and rain gardens provide important habitat for bird and insect species. Adding more native plants also supports more pollinators, which can increase the health of other green spaces in the city as well.

Green infrastructure can, over the lifecycle of the project, save money on rainwater management practices, and contribute to other savings through co-benefits, including health care and building energy costs.

The plants and soils found in many green infrastructure practices filter pollutants out of the water and soil, cleaning rainwater as it passes through. Plants also help remove pollutants from the air.

Proximity to nature and green space has been proven to have significant positive effects on mental and physical health. Green infrastructure can help reduce stress, depression, ADD and ADHD in children, heart disease, obesity, and respiratory illnesses.

Green infrastructure leverages tax dollars to deliver multiple benefits and amenities.

Bioswale, UBC Buchanan Complex

UBC is using landscaping and green infrastructure, like this

bioswale, to manage their rainwater and provide beautiful

public space for students.

Icons: The Noun Project, Photos: Wendy de Hoog

8RAIN CITY STRATEGY


March 2018

Green Infrastructure Tools I

A

B

C

Holes filled with gravel in concrete for drainage

Drainage sand

Crates filled with earth and low maintenance ground cover

A

B

C

ARTERIAL STREET

GREEN STREETCAR

TRACKS

PERMEABLEBIKE PATH

SOIL CELL STRUCTURE

Dome Grate

Plantings

Soil

Concrete Walls

Rock LayerPipe

BIORETENTIONPLANTER

Catch basin with distribution pipe

Sidewalk with tree pits

LOCAL STREET

BIORETENTIONBULGE

PERMEABLE PAVEMENTPARKING LANE

Soil

Concrete Curb

RockPipe

Pavers

Gravel Base

Gravel Sub Base

Pipe

PARK

CONSTRUCTED WETLAND

DAYLIGHTED STREAM

TURFFIELD

Arterial StreetsBioretention Planters are planting boxes designed to use rainwater for their watering needs. These planters collect and filter rainwater and provide an aesthetic function in beautifying our streets.

Street Car Tracks are often paved, but could be vegetated or covered with other surfaces that can absorb rainwater between the tracks and store it below the ground.

Permeable Bike Paths can be paved with porous asphalt, which allows rainwater to pass through it and infiltrate into the soil below.

Soil Cells are carefully designed soil below sidewalks where trees are planted. The structures within the soil allow the roots to grow wide and large enough to support a full grown tree, while also retaining water.

Local Streets Biorentention Bulges are a traffic calming technique that also manage rainwater. They are designed to collect rainwater from the street and catch basins and slowly infiltrate into the soil.

Permeable Pavement can be put in parking lanes, using pervious pavers, similar to cobblestones, which allow rainwater to pass through and infiltrate into the soil below.

ParksDaylighting streams is a practice of bringing paved-over urban streams back to the surface. This allows rainwater to flow more naturally across the landscape, instead of through pipes hidden underground.

Constructed wetlands are purpose-built marshy areas with enormous capacity to store and filter rainwater. They provide important wildlife habitat and can make unique park spaces.

Turf Fields can be designed to allow water to pass through the turf, to be collected in a storage layer. The water can then be infiltrated into the soil, or slowly released into the pipe system after a major rain event has ended.

ARTERIAL STREET

LOCAL STREET

PARK

Illustrations: Nadia Chiu

9RAIN CITY STRATEGY


March 2018

Green Infrastructure Tools II

Light Substrate

Vegetation

Drainage Layer

Protection Layer

INTENSIVEGREEN ROOF

EXTENSIVEGREEN ROOF

PARKADE

HIGH DENSITY

RAINWATER CISTERN

Re-use watergoing into atoilet

Rainwater harvest and reuse

MEDIUM DENSITY

Plants grow in modular casettes attached to the wall.

GREEN WALL

Drainage Layer

Protection Layer

BLUE ROOF

A

A Flow Regulator

BIORETENTIONPLANTER

SIDEWALK

Downspout

Vegetation

Soil

Concrete

RockPipe

LOW DENSITY AND LANEWAY

RAIN GARDEN

DOWNSPOUT DISCONNECT

CISTERN/RAIN BARREL

SOAKAWAY

ABSORBENTLANDSCAPE

PERMEABLEPAVEMENTLANEWAY

LANEWAYHOUSE

High DensityExtensive Green Roofs are layers of plants and absorbent soils on tops of buildings that keep rainwater from flowing down into our storm drains.

Intensive Green Roofs have thicker soil layers that allow larger plants, like trees, and are better suited for use as rooftop park space for people to enjoy.

Rainwater Harvest and Reuse systems collect rainwater and store it to be filtered and reused for things like flushing toilets.

Medium DensityBlue roofs collect water and hold it in a storage layer. Rainwater can then be slowly released into the pipe system after a rainstorm.

Green Walls are plants grown up a wall, either inside or outside of a building. They can insulate a building, and provide important air filtration services.

Bioretention Planters are planting boxes designed to use rainwater for their watering needs. These planters collect and filter rainwater, and provide an aesthetic function by beautifying our streets.

Low Density & LanewaysRain Gardens are gardens designed to collect and filter rainwater before releasing it slowly into the pipe system or letting it infiltrate back into the soil.

Downspout Disconnect programs redirect the water flowing off of roofs from the pipe system to raingardens or other landscaping designed to absorb and use the water.

Cisterns/ Rain barrels are one of many ways to capture and store rainwater for later use, for such as watering your garden, or washing your car.

Absorbent Landscapes are vegetated areas designed to absorb and store rainwater, often in their topsoil. This practice is often used in larger areas, like parks or entire yards.

Soakaways collect water from small drainage pipes, like roof downspouts, into holes filled with small stones that allow water to soak into the surrounding soil.

Permeable Pavement describes forms of pavement, like porous asphalt, that allow rainwater to pass through, and infiltrate into the soil below.

HIGH DENSITY

MEDIUM DENSITY

LOW DENSITY AND LANEWAYS

Illustrations: Nadia Chiu

10RAIN CITY STRATEGY


March 2018

Priorities

Each Vancouver watershed has different assets and different needs. To determine areas of priority, we are proposing a data-driven approach that takes into account various factors, including the six below. Through this process we will develop a sense of each watershed’s needs for new rainwater management practices, and better understand what kinds of practices are most appropriate and effective in addressing each watershed’s needs.

Vancouver’s sewers were originally built to combine both sanitary sewage and rainwater drainage. During higher precipitation periods, the combined volume of rainfall mixed with sewage can overwhelm the capacity of the pipe. This causes a combined sewer overflow (CSO), a mix of sewage and rainwater that flows into our local water bodies. Green infrastructure can supplement sewer separation programs to eliminate CSOs.

Urban areas are typically warmer than their surroundings, a phenomenon known as the “urban heat island effect.” As cities adopt more dense forms of development, vegetation is lost and surfaces are paved or covered with buildings. The change in ground cover results in less shade and moisture to keep urban areas cool. Mapping urban heat can help us determine areas where green infrastructure on the surface would have the most benefit.

A tree canopy of a city is an area covered by the crowns of trees. A denser tree canopy provides important environmental benefits in urban areas, like cooling the area through evapotranspiration, intercepting rainfall with their leaves, and absorbing water at their roots. Areas with a low tree canopy could benefit from having more green infrastructure on their surface. Increasing the tree canopy is also part of the Greenest City Action Plan.

Highly impervious areas, like industrial zones and parking lots, do not allow water to infiltrate into the ground. The presence of these areas has a strong correlation to indicators of poor watershed health, including water temperature, total suspended solids.

Low-lying areas at risk from sea level rise and protected with dikes and pump systems will be susceptible to backwater flooding from upland sources. This makes it especially important to use green infrastructure to control rainwater related flooding in and upstream from these areas.

Areas with especially high levels of pollution will have greater downstream impacts if their rainwater runoff is left untreated, as their pollutants can be carried downstream to affect a wider area. By measuring levels of contamination in catch basins, we can understand which areas have the greatest need for rainwater treatment strategies to be integrated into their rainwater management plans.

Combined-Sewer OverflowsUrban Heat Island Effect

Tree Canopy

Highly Impervious AreasSea Level Rise Vulnerability

High Pollutant Load Areas

Urban heat is more pronounced in the eastern and southern parts of the city.

Significant portions of Vancouver’s coastal areas are at risk of coastal flooding due to sea level rise.

The downtown core and adjacent neighbourhoods have the highest pollutant loads.

Roadways and central neighbourhoods are the most impervious areas of the city.

Vancouver’s tree canopy is concentrated in the western parts of the city, with Stanley Park in the northwest and Killarney in the southeast as exceptions.

Combined sewer outfalls are shown on the map in pink, while the grey line and arrows show Vancouver’s “ridgeline” or high point, and direction of water flow.

How can we prioritize?



March 2018

Quick Start Projects

Action While PlanningThe City of Vancouver is actively integrating modest green infrastructure strategies in a range of transportation and street redesign projects, sewer projects, parks, and private site developments to test their performance. Implementing and monitoring these practices provides City staff and construction and maintenance teams with hands-on experience. Tracking performance lets us learn more about the intensity of green infrastructure practices that will be needed to meet our rainwater management goals. Having these visible and working examples of green infrastructure help create understanding and increase acceptance for these functional landscapes throughout the city.

Quick Starts in the Works

This restoration of Tatlow Creek includes two rain gardens and a constructed wetland that will filter rainwater collected from the surrounding neighbourhood and convey it into the ocean.

Status: Public consultation and design review

The boulevard was identified as an opportunity for green space in the Marpole Community Plan. Boulevard improvements include a rain garden that will manage rainwater using native plants, grasses, and trees.

Status: Under construction

63rd Ave & Yukon St

Tatlow Creek

A series of bioinfiltration trenches are being installed below the bike lane to collect street runoff from the hospital precinct, and allow it to infiltrate into the soil.

Status: Under construction

Two bioinfiltration trenches are being installed below the newly constructed Arbutus Greenway route to remedy a drainage problem, and to treat the rainwater runoff.

Status: Planning

W 10th Ave Bikeway

Arbutus Greenway

There are 23 quick start projects in the works across Vancouver. Some are just beginning the initial proposal phase, others are being designed, under review, or beginning construction. This map shows where you’ll be able to find the projects once they have been completed.

Quick Starts in the City

Look

for the decal!

Water distrubuted through the trench, then slowly released into existing storm sewers, if necessary.

Uptake by roots

Infiltration

Distribution Pipe

Large existing trees

Stone storage

Catch basin

These decals will mark green infrastructure projects as they are built. They will help maintenance workers recognize the projects and give them the appropriate care. It also allows you to find the rainwater management practices in your neighbourhood, and see how the Rain City Strategy is progressing. Keep an eye out!

Illustration: Sam Khany, Sketch: Cameron Owen, Rendering: Kerr Wood Leidal, Photo: City of Vancouver



March 2018

Kitsilano/South Granville

Dunbar

China Creek Still Creek

Balaclava

Angus

Cambie/Heather

Manitoba

Point Grey

South Hill

Vivian

Fraserview

Hastings Sunrise

MarpoleChamplain

Grandview Woodlands

Terminal

Downtown North

Downtown South

Place a sticker on the watershed where you live.Where are you joining us from?

Documents

RAIN CITY STRATEGY - vancouver.cavancouver.ca/files/cov/rain-city-engagement-boards-20180308.pdf · Vancouver’s water ... Most of the pollution in urban waterways is caused by our