WHEN LANDSCAPE ARCHITECTShear the term “stormwater man-agement,” what springs to mind:A regulatory demand? A systemof pipes and ponds designed to be

unobtrusive? Whatever the response,

thanks to revisions to the Clean Water Act,virtually every landscape architect mustaddress stormwater management in virtu-ally every project. As a result, designers aredeveloping many useful strategies for ad-dressing stormwater quantity and quality

on site, but these strategies are typicallygray infrastructure, a simple means tomanage excess runoff. Rarely are these fa-cilities conceived as places for people.

We contend that this growing necessityto manage stormwater on site poses an in-triguing opportunity to transform storm-water management into an on-site designfeature. We call this strategy “artful rainwa-ter design”—design that combines the util-ity of stormwater management with theamenity of rich placemaking focused on therainwater itself. Some creative landscape ar-chitects are seizing this opportunity to createbetter stormwater management systemswhile exploiting the placemaking potentialof rainwater. To help foster this approach, wehave undertaken a selective nationwide casestudy of 30 projects that are acclaimed foraddressing rainwater in ways that are bothenvironmentally responsible and artful. Weare finding that the most inspirational de-signs present a thoughtful and innovativecombination of utility and amenity. By “util-ity” we mean comprehensive and thoroughmanagement of excess runoff rate, volume,frequency, and quality. By “amenity” wemean rich placemaking that intrigues, en-gages, and even educates the visitor aboutrainwater—a landscape that encourages thevisitor to explore what the water is doing,discover how it is being managed on site, andlearn about its environmental importance.

Two exciting award-winning projectswith entirely different strengths can in-form and inspire designers in their ownartful rainwater design efforts. One is10th@Hoyt, an urban apartment court-yard in the Pearl District of Portland, Ore-gon, designed by landscape architect SteveKoch, ASLA. This courtyard captivates thevisitor with its artful display of water con-veyance in a quiet, oasislike space, but itaddresses the utility of rainwater manage-ment less extensively than it could. Theother is the Outwash Basin at Massachu-setts Institute of Technology’s new Rayand Maria Stata Center in Cambridge,Massachusetts, designed by the Olin Part-nership in collaboration with JudithNitsch Engineering. The design presentsa highly innovative rainwater management

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A central water channel on axis with the entry gate combines with bilateral symmetry at the 10th@Hoyt courtyard in Portland, Oregon.

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S T O R M WAT E R S P E C I A L :

RainArt

ART FOR RAIN’S SAKEDesigners make rainwater a central part of two projects.

By Stuar t Echols and El iza Pennypacker, ASL A

ART FOR RAIN’S SAKEDesigners make rainwater a central part of two projects.

By Stuar t Echols and El iza Pennypacker, ASL A

ART FOR RAIN’S SAKEDesigners make rainwater a central part of two projects.

By Stuar t Echols and El iza Pennypacker, ASL A

strategy and breaks new ground in raingarden aesthetics, but it doesn’t engage thevisitor in its exciting on-site rainwater story. The strengths and weaknesses ofthese two designs offer the reader a rangeof ideas to inform future artful rainwaterdesign.

10th@Hoyt CourtyardWalking along a comfortably scaled streetin Portland’s recently gentrified Pearl Dis-trict, one glimpses a broad opening in theotherwise continuous building wall. Abronze-colored gate with a motif of rushesoffers access to an enticing courtyard. Uponentering the small (8,500 square feet) spaceone is struck by the simple clarity of the or-thogonal composition on axis with the en-try. That axis is marked by a vertical copperline running down the face of the five-story building. A seating area of stylishbenches is arranged symmetrically aroundthe axis, establishing an air of serene ele-gance. Oversized black pots surround theseating, each planted with a single shrub;their quiet rhythm defines the central spacewithin the courtyard.

Once the foreground has been absorbed,the visitor’s eye goes to the edges—especial-ly up the faces of the building—where in-triguing surprises reveal the courtyard rain-

water story. The copper line is a rainwaterdownspout from the roof leading to a tall,thin, concrete structure that looks like a skin-ny ziggurat, which in turn steps down to can-tilever over a raised concrete basin filled withround river rocks. The system is designed sothat rainwater from the downspout runsdown the stepped aqueduct and plunges into the rock-filled basin. Other downspouts,tucked into two corners of the courtyard, dis-charge rainwater to similar stepped aque-ducts. Unlike the formal, axial composition

of the first, these two structures zig and zagboth horizontally and vertically, looking likerefined Rube Goldberg contraptions. Rain-water flows down the runnels of these twoaqueducts to wash over Cor-Ten steel levelspreaders, which are perforated by coloredglass dots and perched over rectangularbasins also filled with river rock. The spread-ers are lit from below so that the glass dotsglow at night. Plantings throughout thespace, spare and geometric in arrangementbut varied in hue and texture, offer a lush foilto the hardscape. The whole scene presents aninward-oriented, private oasis where one canwatch rainwater flow.

Visitors are intrigued by the rainwatersystem, their curiosity engaged to follow thewater trail from one structure to another.One of the great strengths of this design isthat people can understand the water pathwhether it is raining or not—thanks to the“chutes and ladders” conveyance system, onecan easily deduce that rainwater movementis the focus of this courtyard. At the sametime, the final chapter of the rainwater sto-ry appears to be missing at 10th@Hoyt. Af-ter its elaborate journey down and into thespace, rainwater simply disappears withouta trace into the river rock-filled basins. Thisvanishing act eliminates open water, oftenconsidered a hazard to small children in un-supervised areas, but leaves one wondering,“What happened to the rainwater?”

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After flowing down the central stepped runnel, rainwater is pumped over sculptural Cor-Ten foun-tains studded with button glass and lit from within, above. This particular conveyance system, be-low, plays hide-and-seek with the plantings, arousing the visitor’s curiosity to follow the water.

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What visitors do not know is that, afterthe system collects rainwater from the build-ing roof and conveys it through the court-yard, the water is then stored in a cistern be-low grade. The cistern holds up to 4,000gallons of rainwater for up to 30 hours andslowly releases the runoff to the citystormwater system through a small valvethat can be adjusted by hand. At the sametime, rainwater detained in the cistern is also recirculated back up to elegant Cor-Tensteel fountains in the courtyard. After circu-lating through the fountains, water drainsback into the cistern, creating a closed loopthat runs as long as there is water detained inthe cistern. When the cistern is empty, thefountains shut down (and consequentlydon’t run at all during periods without rain).By holding excess runoff up to 30 hours, thesystem functions as an extended detentionfacility, allowing time for some sediment tosettle out before excess runoff is discharged.

Although the 10th@Hoyt rainwater man-agement system reduces the excess runoffrate, additional stormwater objectives mighthave been addressed to make its rainwatermanagement even more comprehensive. Ifrainwater had been used to irrigate the lushcourtyard plantings, three other stormwatermanagement issues (runoff quality, frequency,S

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MThe diagram here illus-

trates the rainwater trailsequence from copper

downspout to corrugatedrunnel to Cor-Ten weir

and finally to river rockbasin, below, where water

disappears from view.

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and volume) could also be addressed. Theseplanted areas could be used to filter recir-culated rainwater by simply pumping itto the planting beds, then allowing waterto drain back into the cistern. The soil andplants would absorb water, reducing boththe volume and frequency of water dis-charged to the municipal system. The run-nels and chutes of the captivating con-veyance system could even be directed tothese planting beds so that residents andvisitors could see rainwater being used tosustain the plantings. In addition to thesetreatment opportunities, one more stepcould help tell visitors the whole rainwaterstory: Some diagrammatic signage or visi-bility into the cistern would allow curiousvisitors to comprehend the rainwater storyfrom start to finish. In other words, with afew small changes, this project could more

effectively manage runoff and celebrate howits artful design helps protect Portland’sprecious rainwater resources—a strategy intune with the city’s environmental com-mitment and the growing ethos of its citi-zens. In all, though, the 10th@Hoyt court-yard offers an example of artful rainwaterdesign that is particularly strong in address-ing the idea of rainwater as an amenity andis quite innovative (though limited) inmanaging stormwater.

Stata Center Outwash BasinThe Outwash Basin at the Ray and MariaStata Center on the MIT campus is asunken garden of native plants, river grav-

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Native riparian vegetation, river gravel, and granite boulders abstract a New Englandriverbank in the Stata Center Basin.

el, and granite boulders that control excessrunoff rate, volume, frequency, and qualitywhile reusing rainwater in the building. Itis by far one of the most innovative andcomprehensive stormwater managementsystems we have encountered to date.

The basin is located in a rectangular, asphalt-coated vehicular and pedestrian cor-ridor—a seemingly leftover campus spacesurrounded on three sides by multistorycampus buildings, where one end opens toan ill-defined parking area and green space.Visitors pass quickly through this outdoorcorridor, rarely lingering. Within this grayhardscape, the sunken rectangular OutwashBasin reads as a green object, not as a space.Two adjacent sides of the basin are lined bystepped gabions while the rest of the slopedand sunken garden abstracts a New Englandriverbank: Planted mounds rise above a curv-ing tumble of granite boulders bordereddownslope by a sinuous line of perennials,shrubs, and—in the lowest zone—ripariangrasses. Many of the plantings are arrangedin strong geometric patterns, contrastingwith the naturalistic jumble of boulders andclarifying that this is a human-contrivedlandscape. Overall the design offers an ele-gantly presented river abstraction whose ma-jor strength is its fresh take on rain gardenaesthetics. Rather than the typical profusionof massed plantings found in many rain gar-dens, this design makes a “water” statementthrough the river’s edge theme.

With regard to stormwater manage-ment, this system is multifaceted and thor-ough. Rainwater from the Stata Centerroof and plaza drains through water qual-ity inlets (drop inlets with filters), where itis filtered and discharged into the sunkenOutwash Basin. Two rainwater manage-ment systems are at work in the basin.

The upper system comprises a sunkenbioretention wetland—the visible “river-bank” landscape of planted mounds andboulders sloping down to the sunken zoneof wetland grasses. Retained water lies hid-den below the landscaped surface, visibleonly in the largest of storms. A liner retainsthe rainwater in this upper system, allow-ing water to be absorbed by the plantings.

Excess water overflows into the lowermanagement system through holes in theliner (overflow vents). This lower system isan underground water storage vault madeof sheets of plastic honeycomb grid, stacked

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to create structural voids. Thevault accepts water from both theupper system and adjacent build-ings. A small solar-powered recir-culation system pumps filteredwater from the vault back up tothe bioretention wetland, whereit is discharged beneath the grav-el on the planted mounds. It thendrains, below the surface, downthrough the wetland system andback to the vault. This recircula-tion loop provides continuouswater filtration while it irrigatesthe plants. The vault also servesas a water harvesting system,pumping filtered water back upto the Stata Center for use in uri-nals and toilets.

Last but not least, the entireOutwash Basin sits three feet be-low the elevation of the munici-pal storm sewer system; conse-quently, in large rainfalls excess runoff ispumped up to enter the city system. Thesepumps are used in conjunction with thestorage vault to control discharge rates, vol-umes, and frequencies.

The stormwater utility aspect of this de-sign is extraordinary. Its facilities, work-ing in combination, control the 25-yearexcess runoff rate at the 2-year predevel-opment runoff rate, reduce the volume and

frequency of overflow to thestormwater sewer, control non-point source pollution, and har-vest rainwater for reuse in thelandscape and building. Thestormwater management systemof the Outwash Basin at the Sta-ta Center does it all—a compre-hensive and innovative systemaddressing rainwater quality, vol-ume, rate, and frequency.

Unfortunately, all of this excit-ing activity occurs underground,where it is both out of sight andout of mind. Indeed, the Out-wash Basin design offers no visi-ble water at all—as stated earlier,the rainwater management sys-tem leaves all water below grade(except in the case of a huge rain-storm). Here lies the missed op-portunity of this rainwater de-sign: The fascinating story ofon-site rainwater management iswholly invisible. This artfullycontrived river abstraction doesn’tpresent any facet of the elaborate

hydrological system. And even if the sys-tem were revealed, the basin design doesnot invite interaction: Visitors are not en-ticed to enter this sunken garden. To do so,one either would have to invade the planted

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A steel bridge spans the sunken wetland garden,above, to further emphasize the river concept. Thediagram here illustrates the Stata Center’s subter-

ranean rainwater management system.

areas or hazard the sharp-edged stainlesssteel wire encasing the gabions. Nor arepeople encouraged to sit and ponder thislandscape. In fact, there is no obvious seat-ing provided in the design. Instead, thedesign invites pedestrians to simply walkacross a steel mesh bridge over the “river,”the bridge element helping to emphasizethe river theme. In sum, the elegantlyconceived Outwash Basin neither in-trigues nor engages visitors through itson-site rainwater story, nor does it edu-cate them about the comprehensive andthoughtful way that rainwater is man-aged on this site.

According to MIT campus landscapearchitect Talitha Fabricius, ASLA, whenMIT facilities personnel explain the treat-ment system on guided campus tours,visitors are intrigued, but few visitors tothe site are lucky enough to learn this information. This truly is a missed op-portunity—especially at a technology-focused place like MIT. We acknowledgethat revelation of the stormwater systemmay not have been a goal of the OutwashBasin design, but the rich rainwater sto-ry on this site deserves to be told andcould be accomplished through a rangeof strategies. Visible water runnels couldconvey water to the basin from the build-ings, the recirculation system could beexposed on the surface so that filteredrainwater would be seen drainingthrough the garden continuously, visiblewater could flow in the wetland basin, or,simplest of all, a sign diagramming the

extensive water treatment system couldbe mounted on the pedestrian bridge.

The 10th@Hoyt courtyard and theOutwash Basin at Stata Center have wonmultiple awards for their design innova-tions. Both provide inspirational ideasfor artful rainwater design, with con-trasting strengths in terms of the defin-ing combination of utility and amenity:The 10th@Hoyt design performs an ex-emplary job as a rainwater-focused ame-nity while accomplishing only a portionof the potential range of hydrologicalutility, while the design of the OutwashBasin at Stata Center accomplishes a re-markably thoughtful and thoroughrange of hydrological utility but doesn’tcelebrate the exciting on-site stormwatermanagement story. We propose that art-ful rainwater design can do both, pro-viding utility and amenity to effectivelyunite two critical facets of landscape ar-chitecture: stewardship of water andland and the creation of engaging,meaningful places for people to experi-ence rainwater. LAMLAM

Stuart Echols is a registered landscape archi-tect and an assistant professor of landscape ar-chitecture at Penn State University. ElizaPennypacker, ASLA, is a professor of landscapearchitecture at Penn State. S

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While the rain garden elements suggest an environment shaped by water, the entirerainwater management system functions underground, hidden from view.

R A I N A R TR A I N A R T