Stormwater harms Puget Sound, degrading its water quality, contaminating or recontaminating urban bay sediments, and harming fish and other wildlife. Stormwater also threatens public and private property and drinking water supplies. Much of the harm is attributable to the way we develop land and manage stormwater. Traditional techniques that rely on extensive land clearing and use of pipes and ponds to collect and control stormwater, have not proven effective thus far at preventing harm. Low impact development (LID) is a more environmentally-friendly way to develop land and manage stormwater. LID is a key piece in our approach to manage stormwater.
The Action Team was established in 1996 by the Legislature (Chapter 90.71 RCW) It is the successor to the Puget Sound Water Quality Authority, an independent state agency established in 1985. The chair and staff are part of the governor’s office The Action Team’s mission is to protect and restore the Sound and its diversity of life today and for future generations. The vision behind the founding legislation is to encourage agencies to work together to set goals and measurable outcomes, and carry out needed actions.
There are 3 key components of the Action Team: The Action Team itself – directors of state agencies, local governments, tribal governments, and federal agencies. The Puget Sound Council – representatives from a broad array of interest groups, local governments, and legislators. Finally, Action Team staff – about 19 individuals.
There are two main problems caused by stormwater runoff. First, studies show that after mature Pacific Northwest forest is converted to suburban development, surface runoff increases from about 1% to about 30% (LID Technical Guidance Manual for Puget Sound, 2005). This dramatic increase in surface runoff has led to flooding, property damage, and public safety concerns, and damage to stream channels needed by salmon and other wildlife. After development, much less water infiltrates, since rooftops, roads and other impervious surfaces prevent infiltration. This leads to lower in-stream flows during dryer months, and less water available to recharge aquifers and wetlands. This effects can have profound effects on the Sound’s fish and other wildlife.
Second, contaminants in stormwater have polluted the Sound, leading to restrictions or closures of many productive commercial and recreational beaches. As of 2006, harvesting at several beaches was restricted largely due to stormwater runoff: Lynch Cove, North Bay, Henderson Inlet, and North Dyes Inlet. In addition to these areas, stormwater contributes to restrictions at many other beaches around the Sound.
Stormwater harms fish, too. Recently, federal scientists from NOAA have drawn links between stormwater runoff and Coho dying before they can spawn in several Seattle creeks. The rate of “pre-spawn mortality” ranged as high as 80-90%. Stormwater contaminates, or re-contaminates, urban bay sediments. A multi-year clean-up of sediments in the Thea Foss waterway in Tacoma is now threatened by continuing stormwater runoff that contains pthalates (used in plastic products).
This diagram, from the Low Impact Development Technical Guidance Manual for Puget Sound, shows how water moves over and through the land before development. Before development, the vast majority of water is either taken up by plants or evaporates back to the atmosphere (called evapo-transpiration) or infiltrates (either to become interflow in shallow layers or deeper infiltration. Surface runoff is only about 1 percent, and surface runoff moves to streams, wetlands and other waters very slowly, taking days, weeks or even months to slowly recharge streams, wetlands and aquifers.
This diagram shows averages for suburban development. When forests are cleared, soils stripped away, and roads, rooftops, parking areas and other impervious surfaces are built, evapotranspiration and infiltration decrease and surface runoff increase dramatically. Note that surface runoff has increased from about 1% to about 30%. This is because so much rainfall is stored by trees, other vegetation and soils. These two graphics are representative of the Puget Sound lowlands. They were developed for the LID Technical Guidance Manual for Puget Sound by Curtis Hinman, WSU Extension Pierce County and AHBL of Tacoma. The numbers are approximate amounts, drawn from the collective research of Derek Booth, David Hartley, Rhett Jackson, Rich Horner, Chris May, and others.
Traditional methods to develop land, which still dominate development projects today, result in extensive clearing of trees and other native vegetation and compaction of soils by heavy equipment. Stormwater controls are then added at the end of the site design process to manage stormwater to mitigate the effects of development. Stormwater is managed through a centralized collection and conveyance process, and management occurs far from where the stormwater originated. Stormwater systems are varied, but in most subdivisions use storm drains, conveyance pipes, and stormwater ponds.
In the last 10-15 years, we’ve learned that once a development site’s native vegetation and soils are removed, it is extremely difficult (and costly) to mitigate all the impacts from stormwater runoff. Traditional approaches to stormwater management result in point source discharges from the site and the site’s natural hydrology (particularly the evapotranspiration and infiltration of rainfall) is significantly altered. And traditional BMPs often don’t clean stormwater sufficiently. All of these factors lead to previously discussed problems. Stormwater infrastructure is also costly to build, and costly and difficult to maintain. Often, stormwater facilities are not maintained properly. To manage greater amounts of stormwater, ponds recently are required to be much bigger. This results in often-valuable land being taken up by unattractive ponds surrounded by chain-link fences. Last, traditionally stormwater has been treated as a waste – something to get off of our properties as quickly as possible. This helps with flooding problems, but it doesn’t help protect the Sound.
Example: Here’s a stormwater pond in south Puget Sound. Stormwater here has been imprisoned behind a chain link fence. The pond is not attractive and does nothing for neighborhood, or community esthetics.
Low impact development, or LID, is a relatively new approach to land development and stormwater management. It’s used at the individual project scale. Equally important are broader watershed-wide or basin planning processes. It’s important to remember that LID is an overall approach that isn’t just a certain approach or two – it’s a suite of practices that, when combined, try to more closely approximate a site’s natural hydrology. LID planning protects and uses a site’s natural features: native vegetation, well-draining soils, topography, natural drainages, and so forth, Coupled with many small-scale, distributed stormwater controls, To manage stormwater as a resource close to where it started, on paved surfaces. The LID approach and individual practices can be applied on urban, suburban and rural sites.
Here are the key elements of low impact development: First, assess the site’s topography, soils, natural drainage patterns, sensitive areas, and other key elements. Integrate stormwater management into site planning and design at the very beginning. This often involves a meeting with the developer, builder, and planning, public works and fire and safety staff. Design the site to cluster buildings and other development in a reduced development envelope. Protect sensitive areas and a large percentage of the site’s native vegetation and soils. Understand and work with the site’s natural drainage features. Reduce impervious surfaces by reducing the footprint of buildings, reducing road widths and lengths, and using pervious pavement, minimal excavation foundations, rooftop rainwater harvest, and vegetated roofs. Disconnect impervious surface that is created by using bioretention or pervious pavement. Use multiple, small-scale stormwater controls to manage stormwater close to the source. Maintain the practices and educate landowners.
Although relatively new, LID has shown great promise for offering a better way to protect our water resources. For example, Seattle has been monitoring a project for several years (the SEA Street project) and has found that overall stormwater volume was reduced more than 97%. Several studies show that depending on the site, LID can actually be less expensive to use, especially with new requirements that ponds be much larger to try to provide adequate protection. (When determining the relative cost-effectiveness of LID, it’s very important to factor in the cost of alternative stormwater management and the full life cycle costs. For example, while vegetated roofs are more expensive to build, they’ve been shown to last twice as long, reduce stormwater volume by as much as 50%, reduce city temperatures, and provide recreational amenities to building tenants. Each of those benefits also has a value.) LID creates more attractive livable communities because they have more trees and other vegetation. Traffic studies show that narrower streets slow down traffic and are safer for kids and other pedestrians. LID can also enhance property values by making homes more attractive. The SEA Streets project in Northwest Seattle (117 th Street and 2 nd Avenue NW) is so popular that nearby residents and other visitors routinely walk or drive down it just to enjoy it’s beauty.
Low impact development is just one new set of tools to help us protect resources, but it’s not the only one. LID should never be used instead of the thresholds, standards, and minimum requirements of our region’s stormwater manual, the Stormwater Management Manual for Western Washington, or a locally-developed manual that is technically equivalent. LID is just another way to meet the minimum standards of this manual. LID never replaces effective, local land use planning. This means that jurisdictions should first determine where in each watershed sensitive resources and lands should be preserved, and where future growth will be directed. Once this is determined, LID can be used in designated development areas. Steep shoreline bluffs may not be appropriate for increased infiltration of water (a geotechnical engineer should be consulted). However, certain LID approaches, such as maintaining native vegetation and soils and reducing impervious surfaces, can always be used. LID should be only part of a local, comprehensive stormwater program.
The Puget Sound Action Team has many resources to help bring LID to communities. Action Team staff regularly provide presentations to local governments, community groups, tribal governments, and others. Periodically, the Action Team hosts or participates in education and training workshops. The Action Team web site has a wide variety of publications and links to information. The LID Technical Guidance Manual for Puget Sound, for technical audiences, is available for download or a copy may be requested from the Action Team. Every other year, the PIE (Public Involvement and Education) Fund provides funds on LID and other ways to help protect the Sound.
One of the region’s most important LID tools is the 2005 LID Technical Guidance Manual for Puget Sound . The manual provides the region with a common understanding of the goals and principles of LID, detailed specifications on the practices, and research findings. The manual was authored by Curtis Hinman of WSU Extension Pierce County, with input from an advisory committee and numerous contributors. The Action Team edited, designed, printed, promoted and distributed the manual. Ecology provided funding for its development. The manual is guidance only and is not required. It represents our best current thinking on LID, and will need to be updated as we learn more. It complements Ecology’s Stormwater Management Manual for Western Washington by providing detailed information on the effects of development on water resources and detailed information on LID.
LID uses numerous, small-scale practices throughout the site to manage stormwater. These are called “integrated management practices.” One of the most important practices is bioretention. This is a view of the SEA (Street Edge Alternatives) Street Project in Seattle (NW 117 th and 2 nd Avenue NW). This project uses open street conveyance (no curbs, gutters and storm drains) and long, linear bioretention swales to manage stormwater. UW researchers have monitored the site since 2000. This design has reduced overall stormwater volume by more than 97%. This project was a demonstration site, and Seattle was so impressed by its performance and cost-effectiveness that it’s now being replicated in numerous other Seattle neighborhoods. According to Seattle Public Utilities, this design is actually less expensive to build than a comparable street redesign with comparable treatment.
Amending soils with compost is a great way to build healthier lawns and landscape areas. Soils amended with compost infiltrate stormwater better, reduce watering needs, reduce the need for fertilizers and pesticides, and provide a healthier medium for grass and garden plants. Here you see compost-amended soils in the form of “compost blankets.” The compost blankets are used for erosion control during construction and bioretention swales after construction.
Permeable pavement acts just like regular pavement: You can walk on it, drive on it, and so on. But unlike regular pavement, permeable pavement allows rainwater to soak through, helping reduce surface runoff and replenishing aquifers. There are many different kinds of permeable pavements: Porous concrete (shown here, in Bellingham); porous asphalt, pavers, grass grid systems, and gravel grid systems. A six-year UW study of permeable pavement at a Kent parking lot showed that permeable pavement removes motor oil and dangerous metals: Motor oil was not detected in any samples that infiltrated through the permeable paving sections. (In the conventional asphalt parking spaces motor oil was found in 89% of the samples.) In the majority of samples from the permeable pavement, copper and zinc could not even be detected. (In the conventional asphalt researchers found toxic levels of those metals in 97% of samples.)
Vegetated roofs hold and slowly release rainwater much better than a conventional roof does. Studies in Portland and Europe have shown that a vegetated roof (or green roof or eco-roof) can reduce stormwater runoff volume up to 50%. Vegetated roofs also last much longer than do conventional roofs (2-2.5x longer), they reduce inner city temperatures, and they provide recreational amenities for building tenants.
Roofs generate a lot of stormwater runoff. Rainwater collected from a rooftop can be used to irrigate landscaping, flush building toilets, and, with a proper treatment system, serve as potable water. This is a house on San Juan Island that directs roof runoff to a large cistern hidden underneath the deck. Homeowners in the San Juans have used rainwater harvest systems for years to help meet domestic needs. The King Street Center in downtown Seattle has an extensive rooftop rainwater collection system. The system provides water for the building’s 105 toilets and landscaping. The system saves an estimated 1.4 million gallons per year, meeting over 60% of the building’s estimated annual water needs.
Minimal excavation foundations reduce the excavation and land disturbance that normally occurs when a house or building goes in. Minimal excavation foundations use long pins driven into the earth to secure the foundation. This allows the natural, subsurface drainage patterns of a site to continue as they did prior to development. Tests in crawl spaces of houses with these systems shows normal humidity levels. This is a photo of a new medical complex being built in Olympia.
As one example, the principles of LID, and many of the preceding LID techniques, were applied at a new subdivision in Pierce County. The project is challenging: The soils don’t infiltrate particularly well, there’s a nearby salmon-bearing stream, Hylebos Creek, and an uphill (conventional) subdivision was at one point pouring stormwater onto the project site. The site is about 9 acres, will have about 36 housing units on it, and most of the site’s vegetation was either protected or is being restored.
LID really began on the East Coast, in Prince Georges County, Maryland. This is a subdivision that uses the overall LID approach, protects native vegetation, and uses the vegetation and bioretention to manage stormwater.
Here’s a shot of the King Street Center, in downtown Seattl. Three cisterns hold a total of 16,000+ gallons.
In Everett, Paine Field manages stormwater through the use of a grass pave system (shown here), a plastic grid system filled with soil and grass. This allowed the landowner to reduce the amount of conventional stormwater detention required.
Low Impact DevelopmentMaria Ignatieva
West Coast of the USA• Oceanic climate• Quite high rainfallaverages (920 mm)per year (Portland,Oregon)
Low Impact Developmentin Puget SoundWashington & PortlandOregon, USA
Paradigm Shift• View water as a resource instead of anuisance to contend with duringdevelopment– Replenish aquifers– Store & use rainwater– Remove some contaminants on site anddeliver cleaner water downstream
Overview• Stormwater has harmed, and continues to harm,Puget Sound’s resources (for example, several speciesof Northwest salmon face the threat of extinction,numerous shellfish-growing beaches are too polluted toharvest)• Traditional land development and stormwaterpractices have not proven effective at preventingharm (pollution threatens the health of urban water andunderwater sediments; runoff from stormwater contributessignificantly to these problems)• Low impact development is a key piece in overallapproach to managing stormwater
Effects of Stormwater onWater Quantity• Flooding andproperty damage.• Damage to streamchannels during wetmonths• Lower stream flowsduring dry months,less groundwaterrecharge.Photo courtesy Hans Hunger,Pierce County Water Programs
Effects of Stormwater onWater Quality• Restrictions onshellfishharvest• Harm to fishand otheraquatic life.• PollutedsedimentsPhoto courtesy Taylor Shellfish Farms, Inc.
Many Puget Sound species are harmedby stormwater runoffPhoto courtesy Al Latham,Jefferson Conservation District
Watershed Hydrology BEFORE Developmentevapotranspiration:40-50%interflow: 20-30%surface runoff: <1%
Watershed Hydrology AFTER Developmentevapotranspiration:~25%interflow: 0-30%surface runoff: ~30%
Traditional Approach toLand Development and StormwaterManagement• Most trees and other vegetation areremoved and native soils are compacted.• Management techniques are applied at theend of site design.• Relies on pipes, stormwater ponds andvaults.• Stormwater is managed far from source,after collection and conveyance.
Limitations of Traditional Approaches• Not all impacts can be mitigated.• Infrastructure is expensive.• Maintenance is expensive, often neglected.• Uses a lot of land, often not attractive.• Treats rainwater as a waste, not a resource.
Photo by Stuart Glasoe,Puget Sound Action Team
Low Impact Development• Uses suite of site design elements andpractices.• Mimics site natural hydrology.• Protects and uses site’s natural features.• Uses many small-scale stormwatercontrols.• Manages stormwater close to the source.• Applies to urban, suburban & rural sites.
Key Elements of LID• Assess the site thoroughly.• Integrate stormwater management into sitedesign from beginning.• Design site to cluster development andconserve vegetation, soils, and naturaldrainage features.• Reduce and disconnect impervious surfaces.• Use small-scale practices to disperse andinfiltrate.• Maintain practices and educate landowners.
Benefits of LID• Can better protect water resources.• Can reduce infrastructure costs.• Creates more attractive, livablecommunities.• Can enhance property values.• Helps meet stormwater requirements.
Integrated Management Practices:Bioretention• Bioretention (raingardens and swales):shallow, landscapedareas composed of soiland variety of plantsrain gardens: stand alonefeature-small depressionsnear homes and otherbuildings that collectrunoff from a roof,driveway or yard andallow it to infiltrate into theground.swales: part of aconveyance systemHigh Point, Seattle: SwaleBioswales are shallow depressions created asopened storm water conveyance systems thatare generally not as elaborately landscapedas bioretention systems and are primarlydesigned for transportation and infiltration ofstorm water
Applying LID Principles & PracticesGraphic courtesy AHBL Civil and Structural Engineers
tree conservation • soil amendmentsnarrower streets • open drainage • rain gardenson-site detention, storage and infiltrationPhoto courtesy LID CenterApplying LID Principles & Practices
Example of using LID practice : HighPoint Public Housing Redevelopment inSeattle• 120 acre• Higher density• Mixed-used• Narrow street• Swales• Big retention pond• Pervious pavementHigh Point: Retention Pond
LID examples• 2000-2003 the SeattleStreet Edge Alternatives-SEA Streets project-Seattle Public UtilitiesDepartment• Prevented all dry seasonrunoff and 90% of wetseason runoff• Help protect nearbysalmon streams byreducing stormwatervolume by 99%
Welcome to the virtual tour of SEA Street, a Seattle Public Utilities Natural Drainage Systems (NDS) project located in northwest Seattle. This prototype project, the first NDS project in Seattle,shows a range of unique drainage and street design innovations.The tour begins at the intersection of 2nd Avenue NW and NW 117th Street, and moves north along 2nd Avenue NW to NW 120th Street. At each stop in the tour, labeled on the map of the projectsite below, youll learn about the goals of this pioneering project:Drainage Water Quality Landscape Mobility Community EducationNextPhoto Courtesy Seattle Public Utilities
SEA Street Before….Photo Courtesy Seattle Public Utilities
SEA Street AfterPhoto Courtesy Seattle Public Utilities
Example of LID practice: rain garden inPortland, Oregon
Sustainable Construction Practices inUSALeadership in Energyand EnvironmentalDesign (LEED)• US Green BuildingCouncil ratingsystem for designing,constructing,operating andcertifying greenbuildings.
LEED BuildingsLeadership in Energy and EnvironmentalDesign:• 11 buildings inSeattle: City Hall andCentral Library
US Green Building: Chicago Center forGreen Technology1999 Chicago Department of Environment• Clean-up process of the site• Feature: Increasing Energy Efficiency:1. Window, light fluorescent bulbs2. Smart lights: maximum natural sunlight3. Heating and Cooling Feature: Reducing vehicle emissions Feature: Electric outlets for cars Feature: Public transportation Feature: Bike parking Feature: Local materials
Chicago Center for Green TechnologyOutside: Rain Cisterns- use for watering plants
Chicago Center for Green TechnologyOutside: Solar Energy: Solar Panels
Low Impact Urban Design andDevelopment in New Zealand
New Zealand Low Impact Urban Designand Development ProgrammeLIUDDFRST subcontract: Landcare ResearchNew Zealand Limited, a New ZealandCrown Research Institute2003-2009
New Zealand Urbanization87 % of New Zealand population live in an urbanenvironmentBiggest Cities: Auckland,Wellington,ChristchurchThe fastest growing urban areas by 2021:Auckland (population growth of 36%) and SelwynDistrict (south of Christchurch, 42%).
Urban ecology in New Zealand:Biodiversity of the urban environment• Major concern: loss ofindigenous biodiversity• Problems with naturalizedexotic species (plants,birds and animals)• New Zealand vascular flora:• 2500 indigenous (native)vascular species,• 2500 completely naturalizedalien plants• Over 20,000 exotic vascularplant species• 10% of which have escaped intothe wild• 13 more becoming naturalisedevery year• Native flora gets pushed backinto inaccessible areas• Similar for wildlife
Urban biodiversity and design:New Zealand Low Impact Urban Design andDevelopment (LIUDD)• Apply differentsustainable devices(similar to the USA):swales, rain gardens,green roofs, impervioussurfaces. Compactdevelopment principles.• The key goal is to protectand enhance nativeurban biodiversity• (LIUDD) associated withspecifically employingnative plants andattracting nativespecies of wildlife
“Low Impact Urban Design and Development:Making it Mainstream”• Interdisciplinaryapproach: socialresearchers,environmental scientists,planners, engineers,landscape architects andecologists
LIUDD• Planning & design for physicalsustainability and biodiversity• Relevance (sense of place) andeffectiveness will depend on visibility tothe bulk of the population – in the urbanenvironment
LUIDD: Stormwater best sustainablemanagement practices at catchment scale• Follows the treatment train principle – slowing andlengthening the passage of water moving through theurban catchment from roof to sea or groundwater.• Main roads and secondary roads provide for biofiltrationusing vegetated swale systems. Swale design details from“Stormwater treatment devices from Low Impact Design”manual for Auckland Area• Permeable pavement (less paving areas, shareddriveways)• Detention Pond• Rain gardens, rain cisterns, green roofs for an individualproperty (optional)• Permeable ecological surfaces (driveways) for individualproperties (optional)• Ecological protection, restoration, design at local tolandscape scale
LIUDD• Involve principles of landscape and urbanecology• Alternative, cost-effective design anddevelopment approaches that involve designingand working with nature - creating communityenvironments that respect, conserve, andenhance by or with natural processes• Creating systems of ‘stepping stones’ and greencorridor systems, that can lead native birds backinto cities.• Reintroduction of native biodiversity in urbanenvironment
LIUDD: Overall planning principles of subdivision• Spatial resource survey toidentify significant valuesthat must be protected• Respect existingtopography, landforms andnative vegetation as part ofthe legible landscape• Open green spaces(including native patches);emphasis on theorganisation of commonopen spaces with nativereserves and pedestrianlinkages rather than cul desacs.Concept plan for Regis ParkSubdivision. DJ Scott, Auckland,New Zealand, 2003
2005: Aidanfield (Christchurch)Analysis and developing scenario for LIUDDDesign: Frazer Baggeley, 2005
Ecological Design in Lincoln VillagePropose a System ofGreen Corridors forLincoln Village andsurrounding landscapesPossible connectionsbetween Lincoln Villageand surroundingecosystems such asLincoln University,Landcare Researchcampus, Liffey River andeven Port Hills.Design: James Rea, 2006
Clustaring Houses: saving energy and spacefor habitat• Localised high density;mixed-use subdivisionscan allow larger areas ofpublic open or greenspace• These creates moreopportunities for coresanctuary habitat, ratherthan small fragmented orlinear features withinadequate buffer zoneVegetatedSwaleJ.Collett (2007). Proposal forLiffey Spring Subdivision
LUIDD principles• Provide forpedestrian/bikerecreational loops(public walkways) andlinks from all subdivisionroads. Narrow walkablestreet layout with morespace for pedestrians andplanting (swale planting,street trees, green space)Cross section of walkable narrowstreet for new Liffey Springsubdivision in Lincoln Village,New Zealand. Design: SimonMultrie, 2007
Narrow Roads and StreetsNarrow Road. Lincoln,Christchurch. Photo: RobynSimcockNarrow Road, Talbot Parksubdivision, Auckland. Raingardenon right treating road runoff andforming a traffic-calming feature
LUIDD principles: Formation of storwatertreatment trains• Series of elements or devices linked togetherfrom the top to bottom of the urban catchment(roof to gardens, swales and streets toponds, groundwater and rivers to the ocean)that lengthen and slow the passage of water
Green RoofsA green roof is a roof partially or fully covered by plants.
Rain tanks for an individual property• These and rain barrelsreduce runoff to waterwaysand provide water forirrigation without tappinginto finite aquifers or potablesupplies.• New plantings may needirrigation for the first fewsummers. Rainwater tanksand the retention ofvegetation on uppercatchment large lots are amandatory requirement invarious northern districts ofNZNorth Shore City. Photo: PennyLysar
Permeable ecological surfaces (driveways) forindividual properties• One of the mosteffective means ofameliorating rapidstormwater runoff isto minimise hardsurfaces and to usepermeable materialswhen needed for hardwearing or vehiclestanding.Example of permeable pavingwith grass, Morning StarApartments, Auckland, NewZealand.
Courtyard with four different permeablesurfaces: wooden decking, gravel, permeablepebble pavers (around tree) and grass, atWaitakere Civic Centre, Auckland
LIUDD: Swales and filter stripsMown grass swale, (drainage gate atfront pipes into inflitration bed)
LIUDD: Swales and filter strips• Unmown Carex cv and(Lower) - prostrateCoprosmabioretention/infiltrationstrips at WharewakaTaupo (at least 1 m depthof non-consolidatedmaterial). Note stonedetention dams used toreduce flow strength.Photo: Robyn Simcock
Detention PondVegetated swale and overflow detention pond,Aidanfield, Christchurch, Photo: Colin Meurk
Enhancing biodiversity in the homegarden and public space• We have dealt with the hydrological andecological service function of plants andsuggested a number of indigenous species thatcan be used for these roles.• Under this heading we consider the specificintrinsic values of biodiversity, why we shouldpromote it and how we can integrate it into theurban context.• In particular we focus here on the urban matrix ofprivate gardens and public parks and otherspaces.
Enhancing biodiversity in the homegarden• Trees• Shrubs• Hedges• Rock gardens• Native lawns• Green walls• Herbaceous borders Green wall for private house at LiffeySpring Sbdivision, Lincoln. Design:Jason Collett, 2007
Native lawnGnaphalium audax in a Christchurch Lawn. Photo:Colin Meurk
Rock GardensRock Garden. The Bush City. Te Papa, Wellington
LUIDD in Urban Public Spaces: Parks.Street trees and avenuesNative plants for traffic islands. Wellington
LUIDD principles in action: Waitangi Park,Wellington• LIUDD principles:stormwater treatment andusing native plants ashighly visible and keydrivers of the overalldesign• Representation of raingardens, wetlands, andcoastal vegetation• Designer: M.Wreight
Ecological protection, restoration, designat local to landscape scaleRevegetation of pasture blocks during rural residentialsubdivision at Owhanake, Waiheke Island. Photo:Marjorie van Roon
New Zealand LIUDD practical applications: themanual• How to Put Nature intoOur Neighbourhood:Application of Low ImpactUrban Design andDevelopment (LIUDD)Principles, with aBiodiversity Focus, forNew Zealand Developersand Homeowners
Demonstration Gardens in ChristchurchBotanic Gardens “Design with IndigenousPlants”• Showcase ways toappropriately apply nativespecies in particular settings• Gardens display at a realisticscale of private house situation• How principles of Low ImpactUrban Design andDevelopment can beimplemented into an individualresidential property toimprove sustainability andbiodiversity and reduce costsat both a site, and widerregional scale.
Demonstration Gardens in ChristchurchBotanic Gardens “Design with IndigenousPlants”, May 2008