Landscape Master Plan for the Ajo Plaza

Landscape Master Plan for the

Revitalization of the Ajo Plaza

INternational Sonoran Desert Alliance and Pima Neighborhood Investment Partnership Melissa Carll & HĂŠloĂŽse Chandless | The Conway School Ajo, Arizona | Spring 2011

Index Introduction..........................................................................................1 Goals and Objectives.........................................................................2 Site Context and History.....................................................................3 Existing Conditions..............................................................................4 Analyses

Slopes and Drainage................................................................5

Soils and Vegetation.................................................................6

Sun and Shade..........................................................................7

Views...........................................................................................8

Access and Circulation............................................................9

Legal.........................................................................................10

Historic District..........................................................................11

Summary Analysis....................................................................12

Alternatives

A: First Steps.............................................................................13

B: Bridging the Community....................................................15

C: A Break Through.................................................................17

D: Pedestrian Plaza.................................................................19

Final Proposal: Destination Ajo..............................................21

A: Green Infrastructure............................................................24

B: Palm Substitution..................................................................25

C: Plant Palette........................................................................26

Melissa Carll

Appendix

The Plaza park, Spring 2011

• Evaluate rainwaterharvesting potential

• • • •

South lot Access streets Warehouse Commercial spaces

Provide a vegetation plan for the Plaza • Phased palm tree substitution for Plaza park • Shade trees

Locate parking • 3 RV parking spaces

Implement components of the Sonoran Oasis: Food Security Plan • Site food production space

Melissa Carll, Héloïse Chandless | The Conway School

• Slow car traffic along Route 85

• Decrease irrigation of the Plaza park lawn

Suggest uses for vacant streets & buildings

Prepared for ISDA and PNIP

• Plaza as a visible destination

Address the water use on the Plaza

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Increase the number of visitors (residents and tourists) to the Plaza

Program and objectives

GOALS and OBJECTIVES

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Introduction

The Plaza is transformed into a busy social center during festivals.

The Plaza is a six-acre property in Ajo, Arizona. The town is located in southwestern Pima County, in the heart of the Sonoran Desert. It is 2 hours south of Phoenix and 2.5 hours west of Tucson, en route to Organ Pipe Cactus National Monument, and Puerto Peñasco, on the Mexican coast.

INTERNATIONAL SONORAN DESERT ALLIANCE (ISDA)

Central to the Plaza is its park, a formal lawn lined with palm trees.

Wide arcades run across the front of the commercial buildings surround the park. In addition, there is an undeveloped lot to the south, and a triangle park to the north.

Their vision for the restoration and revitalization of the Plaza is that “it will once again be a thriving economic center, a perfect stopping place for many of the more than a million cars that drive right by each year en route to Organ Pipe Cactus National Monument and the sea coast in Mexico.”

Melissa Carll, Héloïse Chandless | The Conway School

ISDA intends to regenerate the economy of Ajo’s Plaza by incorporating the community, as well as bringing people in from outside of town.

With ISDA’s vision in mind, the landscape master plan begins with the project goals that direct the revitalization of the Plaza.

Prepared for ISDA and PNIP

Susannah Spock

In 2008, the International Sonoran Desert Alliance (ISDA) purchased the Ajo Plaza. Previously, ISDA revitalized the town’s historic Curley School into artist’s live-work spaces, only a few blocks west of the Plaza. It is ISDA’s ambition to revitalize the Plaza area.

Founded in 1993, ISDA is a non-profit organization dedicated to ”working to preserve and enrich the environment, culture, and economy of the Sonoran Desert.”

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Jewel Clearwater

INTRODUCTION

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The Spanish arrived in the 1600s, bringing with them their religion and architecture, and by the 1850s white settlers began to mine the hills around Ajo, but it was not until the early 20th century when open-pit mining techniques reduced costs that a copper mine was opened in Ajo. The design of the town was commissioned by the New Cornelia Mining Company and was planned to house employees from the Tohono O’odham, Mexican and Anglo communities. The Native American population was segregated to “Indian Village” and the Mexicans to “Mexican Town,” while the Anglos lived in what is now the historic district neighborhood surrounding the Plaza.

With the town’s economic decline, it is ISDA’s mission to revive the economy of Ajo. They want to start by bringing the town’s heart, the historic downtown and Plaza, back to life.

Tohono O’odham man, c.1880

Ajo Plaza after completion, 1920s

Races on the Plaza, 1920s

Ajo Plaza, 1960s

Ajo Plaza, c.1939

The Sonoran Desert is an ecoregion that covers nearly 100,000 square miles.

Melissa Carll, Héloïse Chandless | The Conway School

The Tohono O’odham were the first known people to have adapted to the Sonoran Desert. For tens of thousands of years they subsisted by using a form of nomadic flood farming called “ak-chin,” which took advantage of the desert’s sporadic rainfall.

Indian Village and Mexican Town long are gone, and most of the town’s 3,300 inhabitants live in the historic downtown and the newer sections of town to the north.

Prepared for ISDA and PNIP

Temperatures in the desert range from 57 ºF in the winter (occasionally dropping below 32ºF) to 120 ºF during the summer months. The average record for annual rainfall is 7.5 inches, and yet the Sonoran Desert is lush, home to 2,000 plant species and about 500 animal species.

The mine closed in 1984, taking with it many of the town’s available jobs.

Today, around 55,000 square feet of a total 90,0000 square feet of retail space remains unoccupied.

Ajo’s commercial district has mostly relocated from the Plaza to newer commercial units on the town’s north along Route 85.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

The backdrop to Ajo’s story is the Sonoran Desert, a biome which covers approximately 100,000 square miles of southern Arizona, southeastern California, most of the Baja California peninsula, and most of the state of Sonora, Mexico.

SITE CONTEXT AND HISTORY

SITE CONTEXT AND HISTORY

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Bandstand Parking

Existing Conditions Around the Site Ajo Regional School Triangle Park

Arcade Library H UT IAL SO ERC G MM DIN CO BUIL

Traffic Light ad

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Catholic Church

Detail of Plaza Park

Federated Church

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Chamber of Commerce Bank

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Restaurant Curley School

te ou

R Warehouse

Not for construction. This drawing is part of a student project and is not based on a legal survey

Flagpole

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Opposite the Plaza, across Route 85, are the Catholic and Federated churches. ISDA’s second property, the Curley School, lies an unshaded tenth of a mile, at the other end of Lomita Avenue.

Median

85

The Plaza has 60 parking spaces for cars. Traffic circulates one-way, clock-wise, around the park. Along the west side of the Plaza, Route 85 hugs the property boundary.

Parking

ute

The storefronts are shaded by a 16-foot-wide arcade, which runs the length of the commercial area, connecting across the eastern street to a former train depot.

Arcade

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Across the street from the south commercial building is the Chamber of Commerce, a bank, and a popular bar and restaurant, the 100 Estrella.

D.E.S.

South Lot

Small commercial building

100’

85

100’

Melissa Carll, Héloïse Chandless | The Conway School

The north or triangle park is in the process of becoming a wildlife garden. High walls at the back of the park will display murals and town history plaques.

H AL I RT NO ERC G M M DIN CO BUIL

Dance hall

Prepared for ISDA and PNIP

The park is flanked by two commercial buildings, in the past run by the mining company but now owned by ISDA. The Plaza’s active businesses include a cafe, a pharmacy, specialty stores, library, post office, and the Ajo Department of Economic Security (D.E.S.). These businesses occupy a third of the available commercial space.

Movie Theater

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

South of the Plaza is a large, mostly empty lot with an 80-foot-wide road along the east boundary. There are two buildings in the south lot: a vacant warehouse and a smaller vacant commercial building. The mine’s disused railroad and a wash cut the site off from the Ajo Regional School.

Post office Oasis Café

T PO DE

The 6-acre Plaza property forms the southeastern boundary of the National Register Ajo Townsite Historic District. The focal point of the Plaza is the Plaza park, a lawn transected by walkways and bounded by palm trees and historic bollards. A closedup, filled bandstand sits in the middle of the park.

Existing conditions

EXISTING CONDITIONS

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Analysis: slopes and drainage

RR

Wash

The Plaza park drops 4 feet from Route 85 to the train depot.

RECOMMENDATIONS It will be necessary to assess the viability of buried cisterns, pumps, and piping to create a rainwater harvesting system. Pollutants may be found in street runoff water, so testing will be required to establish the viability of using runoff water for irrigating food crops, as well as the Plaza lawn and green infrastructure.

In order to harvest roof runoff for use on food plants, the quality of the water would also need to be tested for pollutants. A cost evaluation for rainwater harvesting is recommended.

Drainage Patterns Through Town

Runoff flows from “A” Mountain through historic district toward the Plaza where it pools at the traffic intersection.

Depot

Drainage Patterns Around Plaza

water drainage water pooling

h

There is potential to capture runoff

Access road

Plaza park

s Wa

The impervious roof surfaces cause further complications, where runoff from the south commercial building pools along the access street.

Route 85

Wash

Melissa Carll, Héloïse Chandless | The Conway School

The park slopes 4 feet from one end to the other along its length. Drainage challenges arise because of the region’s precipitation patterns and the built environment in town. Average rain per annum is 7.5”, with light rains during the winter months, and sudden, dramatic storms in July and August, that can cause flash floods to run in the washes. Impervious town streets are channels for water run-off and during severe rain events flooding occurs where the streets converge at the Plaza, causing traffic problems.

water from the 70,000 square feet of roof-surface to irrigate some of the park’s lawn (currently, irrigation consumes 2,500,000 gallons of water per year), or to create green infrastructure, such as vegetated swales, which could be used to grow native shade plants. Captured stormwater runoff would need to be stored in tanks or cisterns.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Ajo lies on the northern edge of the Little Ajo Mountains, with open valley stretching to the north, with a 1,000 foot change in elevation (2,500 ft to 3,500 ft, respectively). The Plaza park is half a mile from “A” Mountain.

Section: Plaza Park

Prepared for ISDA and PNIP

slopes and drainage

“A” Mountain 0.25 miles

Not for construction. This drawing is part of a student project and is not based on a legal survey

100’

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RECOMMENDATIONS

Testing for soil contamination is needed to establish the viability of soils for food production, particularly around the depot.

Providing the soils are suitable for food crops, the application of organic matter would help the soil’s water retention capacity and should help reduce the pH levels. High nutrient levels suggest that no fertilization is required.

SOIL TYPES AROUND AJO

The Plaza park palms (especially the desert palms) are reaching the end of their lives, a lifespan that ranges 100 to 150 years.

The date palms contribute to the visual integrity of the Plaza, and provide shade.

Lack of vegetative shade in the Plaza may limit its use during hot days.

Jacaranda trees and pinyon pine are not plants on the historic planting plan, but they do provide some shade.

Non-native vegetation, or vegetation illadapted to the arid climate, struggles to survive. 2,500,000 gallons of water are used per year to maintain the appearance of the cool-season grass turf, and non-native plants.

RECOMMENDATIONS The opinion of an arborist should be sought to determine the viability of all the trees in the park.

New vegetation on site should be native or adapted to the climate. Substituting native plants for turf would reduce the irrigation requirements and cost.

Plaza

23 Not for construction. This drawing is part of a student project and is not based on a legal survey

Information from USDA and NRCS, 2010

37

Review irrigation methods, times, and system, and plant warm-season grass to reduce water consumption on the lawn.

The south lot should be greened with native plants.

Designs should respect the historic planting plan to maintain the historic district’s integrity. A phased substitution plan for the palms will help sustain historic vegetation (see Appendix C).

Rainbow barrel cacti line the median by the depot. The cactus has hooked barbs, but attractive colors.

Oleanders are a historic component of the park, but they do not provide much shade, and are poisonous. New designs should replace this plant.

EXISTING VEGETATION: Phoenix dactylifera date palm Washingtonia filifera desert palm Pinus edulus pinyon pine Rhus lancea African sumac Jacaranda mimosifolia jacaranda Echinocactus grusonii barrel cactus Opotunia basilaris prickly pear Encelia farinosa brittlebush Parkinsonia aculeata palo verde Sphaeralcea angustifolia globemallow

Melissa Carll, Héloïse Chandless | The Conway School

The south lot has sparse vegetation.

53

40

70’ desert palms and 50’ date palms add a vertical accent to the Plaza. The palm trees provide shade, but the date palms are not native.

Sprinklers irrigate the lawn, often during the day when evaporation rates are higher.

Soil series 37: Gunsight-Rilito-Carrizo complex (62.9% of town) Soil series 40: Hyder-Gachado-Gunsight complex (12.1 % of town) Soil series 53: Quilotosa-Momoli-Carrizo complex (9.9% of town) Soil series 54: Quilotosa-Rock Outcrop complex (9.6 % of town) Soil series 23: Dumps-Pits Association (5.5 % of town)

54

Prickly pear cactus grows along the traffic median. This plant is a native food source, and has beautiful blooming flowers.

Prepared for ISDA and PNIP

The excessively-draining soils, the high pH levels, the arid conditions, and the extreme heat all limit the plants that will tolerate conditions on site.

The choice of vegetation should be native to the Sonoran Desert, or plants viable in alkaline soils in USDA Zone 10a.

Palo verde trees dot the south lot. Native and self-seeded, they survive unaided, demonstrating their viability as a source of shade on the property.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

The soil onsite is an extremely gravelly, sandy loam, low in organic matter, and is excessively-drained. Initial test results indicate extreme alkalinity, between 7.6 - 8.1 pH. All samples demonstrate high nutrient levels of phosphorus, potassium, calcium, and magnesium, which is beneficial for plant growth. Samples from the depot show high levels of copper and sulphur.

ANALYSIS: Soils and Vegetation

VEGETATION

SOILS

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ANALYSIS: Sun and Shade

SUN AND SHADE The Plaza experiences up to 14 hours of sunlight in summer. Temperatures have been known to reach 120 ºF at points in June and July. The winter months are generally mild and sunny.

RECOMMENDATIONS

The expansive town plan means that vegetation and buildings provide little shade: only the date palms provide shade in the park, and there is virtually no shade on the south lot.These conditions reduce visits to the park during hot weather.

Increased shade throughout Ajo will mitigate the heat island effect and reduce air-conditioning of buildings.

Lack of shade increases the transpiration rate of vegetation.

High transpiration rates increase the amount of irrigation neccessary for the lawn.

The high amount of sunlight makes the Plaza a great location for solar panels:

Shaded sidewalks and paths will improve the walkability of the town and park.

Shaded spaces for activities in the park will encourage people to use the Plaza.

9am

9am

12pm

12pm

5pm

3pm

• Excess energy can be sold back to the grid.

• Visible photovoltaic arrays may serve to educate visitors about the benefits of solar energy harvesting.

• Raised photovoltaic arrays can provide shade for parking or recreation areas.

The Ajo Improvement Company offers incentives to properties to install solar panels.

Left: The palm trees do not provide sufficient shade for people to want to spend extended amounts of time in the park.

Not for construction. This drawing is part of a student project and is not based on a legal survey

Above: During the summer months there is little shade on the park, except in the evening. ISDA programming and use of the Plaza during the daytime may be limited without increased shade, especially on the lawn.

Above: In the winter, shade stretches in wide patterns across the Plaza, and from the commercial buildings across the parking areas.

Midday use of the Plaza is cooler, making the site pleasant for outdoor eating or walking.

Melissa Carll, Héloïse Chandless | The Conway School

• The aspect toward which the south lot faces makes it an ideal location for solar panels.

Prepared for ISDA and PNIP

• Photovoltaic arrays on the Plaza buildings can provide energy for the site. PVs on the roofs would generate approximately 93,300 KWH/ month.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Ajo receives sunshine 300 days (or more) per year.

Winter Solstice - December 21

DRAWINGS NTS

Heat absorbent surfaces such as roofs, streets, and sidewalks take up heat and increase the temperature.

This heat island effect increases the need for buildings to be cooled, and may contribute to the absence of pedestrians and cyclists in the town and the domination of car use.

Summer Solstice - June 21

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RECOMMENDATIONS

Passers-by do not perceive that they are driving through the historic town center. The Plaza property along Route 85 lacks adequate signage or appropriate visual cues that signal the Plaza is a place where they want to stop.

Another challenge to the Plaza’s revitalization is that the commercial buildings do not have visible storefronts on Route 85.

Views to churches Undesirable views

The prominence of the axis to town history means that designs should not block views along the axis.

Wash

Mirroring the Plaza’s architectural elements (such as historic bollards) and vegetation on the west side of Route 85 will help indicate to cars driving through that the Plaza is a destination.

Depot

Increasing visible commercial activity along Route 85, providing parking areas, and improving store fronts and signage will draw in more people.

Catholic Church

Clarlifying the different functions and spaces of the south lot (eg., defining the road and sidewalks) will improve the arrival experience into Ajo from the south.

Providing vegetative and structural shade will make the south lot more enticing to people traveling along Route 85.

Federated Church Curley School

View into South Lot

100’

The vacant south lot is the first impression of Ajo for visitors arriving from the south.

Section Along the Axis

View Along Town Axis

Not for construction. This drawing is part of a student project and is not based on a legal survey

The view from Plaza to Curley School along the axis is a highlight of the property.

A Mountain (cross on top)

Ajo Historic Townsite

Curley School

Church

Plaza park Depot

Prepared for ISDA and PNIP

The first views of the Plaza from Route 85 are of the two prominent churches, attracting attention away from the Plaza, and reducing the liklihood that tourists will see the Plaza and stop.

View along central axis

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

The character-defining view in Ajo runs from “A” Mountain, through the Curley School, to the historic train depot. The view follows the town axis, an imaginary line along which the historic district was designed.

ANALYSIS: VIEWS

Views Around The Plaza

Melissa Carll, Héloïse Chandless | The Conway School

VIEWS

Wash

Ajo was designed along the town axis—an imaginary line running from “A” Mountain to the train depot. The views along the axis are important to the community.

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Traffic Light

Shaded connections between town and the Plaza will encourage pedestrians to walk or cycle to the site. Shading both the park and south lot will encourage use of the park and improve pedestrian access between businesses and through the space.

G

CIRCULATION

Traffic light

South lot

100’

Far Left: The back street, a local cut-through, on the south lot could become a more prominent route into the Plaza, but its current lack of definition can be confusing, especially for people from out of town.

Not for construction. This drawing is part of a student project and is not based on a legal survey

Left: Park sidewalks are lined with new benches, but little shade and lack of businesses leave the park under-used.

Melissa Carll, Héloïse Chandless | The Conway School

SB

ad

Informational signage will help make visitors aware of atrractions around the town.

ING

D UIL

Prepared for ISDA and PNIP

SIGNAGE

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Signs placed along the Plaza’s street frontage can encourage people to stop at the businesses.

Ajo Regional School

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Limited business activity and lack of shade in the park does not encourage pedestrian traffic around the Plaza.

IN ILD

U

NB

There is potential to change the location of the traffic light, amend traffic patterns, and increase business visibility to encourage visitors to stop.

Connecting the school to the Plaza will improve pedestrian access.

ANALYSIS: Access and Circulation

Pedestrian Circulation

SHADE

There are few signs indicating access to and commercial activity around the Plaza.

Hot, unshaded streets discourage pedestrian or bicycle journeys to the Plaza. Students walk along Route

Minimal Traffic

h

Local cars and students cut through to the Plaza via the south lot.

RECOMMENDATIONS

Major Car Traffic

s Wa

The most direct access to the Plaza is from Route 85. Traffic circulates one-way around the park. Despite the slowing of traffic at the light, south-bound traffic on Route 85 cannot turn into the Plaza. Locals are aware that other access points exist: by the triangle park or by the south lot. However, there are no signs to indicate these turns to visitors, and furthermore the south lot is not visually encouraging to passing traffic.

85 to get to the site because the railroad and wash prevent them from crossing at the shortest distance.

85 ute Ro

One million cars per year pass along Route 85, Ajo’s major road, but few cars stop in the Plaza, even though the road hugs the entire western property line.

Access to and Circulation Through Plaza

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Access and Circulation

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ANALYSIS: LEGAL

Zones Around the Plaza

The Plaza’s lenient zoning restrictions give it the potential to grow in a number of ways: it can attract a variety of businesses from restaurants, boutiques, child care or elder care facilities to a small production, such as an aquaponics (fish farm) in the warehouse.

Additional parking spaces could be placed along Route 85. Any changes in parking along the route would require the county engineer to come and study the condition, width, and average traffic load of Route 85 along the Plaza property.

The engineer’s recommendations would need to pass approval at the county level court (10.40.040 Recommendation of engineer, Pima County Planning Code).

Two other zones, CB-1: Local Business zone, and CR-4: Mixed Dwelling Type zone surround the Plaza site, but they do not affect potential changes made on the property.

Plaza

Curley School

N

0.25 miles

Zoning Designations in Ajo

Currently, commercial businesses on the Plaza property surround the park.

However, if businesses expand to the vacant buildings, or into the south lot, there may be need for parking along Route 85.

Plaza

CB-2: General Business Zone CR-4: Mixed Residential

The Plaza is zoned CB-2: General Business ,which allows ISDA to use the space as a place for commercial entities, mix-used residential, or small scale industry business.

Not for construction. This drawing is part of a student project and is not based on a legal survey

Prepared for ISDA and PNIP

The Plaza property is surrounded by several other zones. The two churches are both part of the TR: Residential transitional zone, which allows for residences or businesses such as child day care or community centers. Another CB-2 zone stretches along Route 85 in the north section of town—this is where many of the commercial businesses are now located.

Recommendations

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

The Plaza is zoned CB-2: General Business Zone. This is Pima County’s most lenient business zone, allowing for a variety of commercial activities mixed with residential use. Businesses are allowed to sell wares inside or outside their commercial building space. Small industrial units are allowed to operate within CB-2.

Setbacks for potential new building construction around the property must adhere to the 15’ from the roadway. ISDA’s Curley School is also zoned CB-2.

Melissa Carll, Héloïse Chandless | The Conway School

LEGAL

CB-1: Local Business Zone TR: Transitional Zone

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Spatial Organization and Land Patterns Topography Vegetation Circulation Water Features Structures, Furnishings, and Objects Accessibility Health and Safety Environment Energy Efficiency

Vegetation and Energy Efficiency The lawn is a character-defining feature of the park, but it requires substantial irrigation (2.5 million gallons/year).

Recommendation Consider a balance between historic precedent and environmental considerations—small portions of the lawn can be removed to cut energy costs and replaced with native plants.

Recommendation Reopening the bandstand will help restore the“feeling” (the quality of integrity) of the Plaza.

Health and Safety The original planting plan for the park includes oleanders— however, current considerations allow for the removal of vegetation that may be cause for health concerns (oleanders are poisonous).

Changes can be made to a historic cultural landscape, as long as they do not harm the integrity of the characterdefining features.

Not for construction. This drawing is part of a student project and is not based on a legal survey

Recommendation Vegetation may be substituted with plants that provide the same aesthetic function, and new vegetation should maintain the spatial arrangement of the original planting plan.

Melissa Carll, Héloïse Chandless | The Conway School

According to the Secretary of the Interior’s Guidelines, there are seven qualities that determine historic integrity of a place. The Plaza is missing one: “feeling.”

Considerations for Cultural Landscapes • • • • • • • • • •

Recommendation New pathways can be added to improve pedestrian movement across the park. They should be made of a different material (preferably pervious pavers, or packed local gravel) to distinguish them from historic walkways, and their design should complement the original symmetrical organization of paths.

Structures, Furnishings, and Objects The bandstand was an original component of the park, but it was closed and filled with concrete.

Qualities of Integrity Location Setting Feeling Association Design Workmanship Materials

Spatial Organization and Land Patterns and Circulation Walkways around the Plaza park were designed in accordance with the City Beautiful movement, and as such their spatial organization is an important part of the historic designed landscape.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

characteristics that existed during the property’s history” (Secretary of the Interior’s Guidelines). Integrity is broken down into seven qualities, and the “significance” of a property is determined by its qualities.

Currently, the Plaza and park are missing the quality “feeling”—this intangible quality relates to the sense or perception of the space. The Plaza no longer operates as a town center or central commercial district A historic district contains buildings and landscapes that are “character- with the sight and sound of many people enjoying the Plaza on a daydefining features,” elements that add to the significance of the district, to-day basis. such as the Plaza and park. Special The integrity of the landscape of the considerations should be taken Plaza and park can be improved. when making changes to these The character-defining features of components so that the integrity of the district can be rehabilitated to the entire historic is maintained. help fulfill ISDA’s vision of a revitalized Plaza property.

Historic integrity is “the authenticity of a property’s historic identity, evinced by the survival of physical The Plaza and park are part of the National Register’s Ajo Townsite Historic District (#01000877). The park is a historical landscape designed as part of the City Beautiful movement, and falls under the Secretary of the Interior’s Guidelines for the Treatment of Cultural Landscapes, that protect special historical and cultural landscapes.

• • • • • • •

Analysis: historic district

Considerations and Recommendations for Plaza Landscape

Prepared for ISDA and PNIP

historic district

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Legend Major car route Minimal traffic Pedestrian circulation View to churches View along axis ute Ro

Undesirable view

85

Water pooling

Ajo Regional School

Ra ad

ilro

ING

ILD

U SB

Federated Church

Traffic Light South lot

Curley School

e

t ou

R

85

Sun and Shade: • The Plaza is sunny much of the year.

• The Plaza park receives shade mornings and evenings during summer, and increased shade in the winter.

• South lot is exposed to sunshine year round.

Design Directive: Increase shade (vegetation and structures) in areas designed for public recreation.

Melissa Carll, Héloïse Chandless | The Conway School

h

t

Not for construction. This drawing is part of a student project and is not based on a legal survey

Design Directive: Reduce cool-season grasses to minimize irrigation, increase native vegetation, and plan for the substitution of the aging, historic palm trees.

po

Catholic Church

Drainage and Slopes: • Water drains from “A” Mountain to the wash.

• Water pools on the south side of the Plaza park and the south commercial building.

Design Directive: Assess rainwater catchment systems to diminish excess water runoff.

Consider harvesting rainwater for food production or irrigation of the lawn.

De

Design Directive: Draw tourists attention to the Plaza instead of the churches, to increase the number of people who stop.

Design similar street frontage on both sides of Route 85 to suggest to drivers that they have come to a destination.

Highlight the view along the town axis.

ING

ILD

U NB

Vegetation: • Cool-season Bermuda grass turf • Historic palm trees (native and nonnative) • Sparse vegetation in south lot

s Wa

Views: • Views from Route 85 north and south face churches, not the Plaza.

• Town’s most compelling view is along the axis.

Prepared for ISDA and PNIP

Design Directive: Reroute traffic to create a more recognizable and intuitive entrance into the Plaza (especially to encourage tourists to stop).

Design Directive: Shade trees in the park and where possible along roads and streets will encourage pedestrian access, as will improved crosswalks. Sidewalks on the Rt 85 end of the park will improve safety.

Drainage

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Traffic Circulation: • The heaviest traffic is along Route 85 (a million cars pass through Ajo on this route each year, but few cars stop).

• One-way traffic does not enter the Plaza at the traffic light, but at the north commercial building.

Pedestrian Circulation: • Lack of shade prohibits the number of pedestrians willing to walk to, and circulate around the Plaza site.

• Lack of connections (especially crosswalks) do not encourage foot traffic to cross roads and streets.

• There is no sidewalk at the west end of the park, on Route 85.

Summary Analysis

Summary Analysis

100’

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ISDA’s tents line the lawn, and can be moved for a variety of programming.

Vegetated swales hug the top of the Plaza, drawing attention to the space, and capturing stormwater run-off.

Ajo Regional School

Community gardens line the property along the railroad tracks where they receive ample sun, and food stands attract both visitors, and school students to the south lot.

Pedestrian walk and outdoor eating space

g

a

rci

e mm

ld lB

o

NC Shade Tents

New vegetation helps shade the back street and the top of the Plaza. Traffic circulation remains unchanged. The entire Plaza site becomes a gathering space for the community.

Vegetated swales Shade trees to Curley School

ial

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g Bld

Tree-lined parking

A’

om

Concept Drawing

A

SC

RV parking

Parking

Food production

Vegetation Pedestrian Area

Curley School

Bar/Cafe Food stands

Traffic Circulation 100’

Shade

Section A-A’: People relaxing at prominent outdoor eating areas entice others to stop at the Plaza. A 100’ crosswalk from the arcade to the park slows traffic and creates a pedestrian-friendly area on the street. Vegetated swales capture rainwater.

NTS

A’ Not for construction. This drawing is part of a student project and is not based on a legal survey.

Parking

Pedestrian walk and eating area

Parking

Swale

A

Melissa Carll, Héloïse Chandless | The Conway School

New crosswalks provide a balance between vehicular circulation and pedestrian activity. The wide pedestrian crosswalks also has room for umbrella-shaded tables.

Community gardens

Parking for the warehouse business sits along its south facade, with RV parking along the street.

Prepared for ISDA and PNIP

Alternative A focuses on revitalizing the Plaza as a community space, and meeting ISDA’s goals for the Plaza property with minimal infrastructure changes.

Fewer parking spots around the Plaza park make room for 100’ wide, shared pedestrian pathways that cross vehicular traffic. New shaded parallel parking spaces are added south of the depot.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Overview

Alternative A: FIRST STEPS

Alternative A: First Steps

13 /26

CONS

• Wide pedestrian crosswalks connect commercial businesses to the park and have shaded outdoor seating areas.

• Vegetated swales along top of Plaza capture runoff.

• Food stands along south lot bring in tourists, or students from regional school.

• There are over 12,000 square feet for food crops and community gardens.

• The current confusing traffic pattern remains the same.

• Parking spaces are limited on the Plaza.

• The lawn is not reduced, and irrigations requirements remain the same.

Wikicommons

Bandstand

PROS

A mixed-use street space in Holland. The street around the Plaza park can function in a similar way with pedestrians and cars having equal importance within the space.

A “kiosco” or shaded cover over a bandstand is found in many Spanish plazas. Once the Plaza bandstand is reopened, people can enjoy sitting in the middle of the park under the cool awning.

Outdoor eating area

ldg

B ial

erc

m om

C

Shade tents

Raised pedestrian walk

al rci

me

Traffic light

Not for construction. This drawing is part of a student project and is not based on a legal survey.

S

m Co

g

Bld

Melissa Carll, Héloïse Chandless | The Conway School

Semi-permanent shade structures on the Plaza create a welcome cool place to sit. They can be modular units allowing for flexible division of the park’s space, and for a variety of uses.

Prepared for ISDA and PNIP

Shade: Tents Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

N

Alternative A: Details

Alternative A: Details

14 /26

Overview Alternative B addresses connections to the Plaza from the surrounding community.

Pedestrian walkways connect to Plaza businesses, and a new path with a bridge over the wash incorporates the regional school.

The park is shaded with structures, as is as the alleyway behind the south commercial building.

Traffic circulates two-way through the Plaza, enabling visitors to turn down either of the Plaza street. The traffic is slowed by two pedestrian crossings between the commercial buildings. Additionally, the parking is single-loaded along the commercial buildings. Pomegranate trees help shade parking along the property

perimeter, and provide food for the community.

B

Town residents visit the Plaza to put their feet in the new water feature or to sit under beautiful ramadas.

Pomegranateshaded parking

A pollinator garden on the rim of the bandstand’s paved area reduces the lawn without disrupting the appearance of the park.

Increased physical connections to the Plaza—such as the bridge across the wash, or an enlarged pedestrian walkway around the top of the Plaza—make walks to the space enjoyable.

Community members can sell their crops at the farmers market that operates out one half of the warehouse, while there is room for RV parking inside the other half.

r

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N

Ajo Regional School

g

Bld

m Co

Alternative b: Bridging the community

Alternative B: Bridging the Community

B’ Bridge B ial

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Shade trees to Curley School

S

m Co

Toldo: street shade

ldg

B

Farmers market

Library

Community gardens

Curley School

Pedestrian Area

Food stands

Traffic Circulation

100’

Shade

Section B-B’: A shaded bridge creates a walkable connection between the regional school and the Plaza, and allows students to visit the Plaza during their lunch break.

NTS

Not for construction. This drawing is part of a student project and is not based on a legal survey.

B’

Regional School

Wash

Mine Railroad Tracks

Depot

B

Melissa Carll, Héloïse Chandless | The Conway School

Vegetation

RV parking

Prepared for ISDA and PNIP

Parking

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Concept Drawing

15 /26

Toldos: Street Shade

CONS

The library can use the adjacent vacant building (west of the warehouse) as a breezy, shaded, outdoor, reading-room. The rear of the south commercial building is converted into more live/work/retail units with street frontage along the currently unused access street.

me

N

m Co

Toldos shade busy commercial streets, providing agreeable microclimates, in Madrid.

Warehouse: Shaded Community Space or Farmers Market

Pollinator habitat

Shade structures

Children’s play area

Fountain

Ramadas al rci

Walkway

g

Bld

me

S

m Co

Library

Not for construction. This drawing is part of a student project and is not based on a legal survey.

se

ou

W

h are

France,Voyages

Toldo: street shade

Above: The warehouse has an open interior; dividing the space improves its rentability. By removing the walls from the eastern end, the remaining structure can become: • an open-sided market-place, or shaded community venue (east end).

• a sizeable retail space with street frontage and parking (west end).

Left: A covered market in France dating back to the middle ages.

Melissa Carll, Héloïse Chandless | The Conway School

g

Bld

Prepared for ISDA and PNIP

al rci

Sara Matthews

• A bridge connects the Plaza • A potential need for a second traffic light to to the regional school. mitigate two-way traffic • Increased shade across site.

• A new commercial area is turning from or onto Route sited on the access street.

85.

• Improved two-way car access • The local vehicular cutthrough street in the south through the Plaza park. lot is blocked for food • A farmers market is sited in the warehouse. production space.

• The gathering area at center • Pedestrian circulation improved is improved with an of park may be hot and expanded sidewalk around sunny during the afternoon. top of Plaza.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

PROS

Alternative b: Details

Alternative B: Details

16 /26

The Plaza integrates green infrastructure such as vegetated swales planted with native trees to help reduce the urban heat island effect, and capture runoff. A vegetated median on Route 85 helps slow the traffic, encouraging drivers to turn into the Plaza along the south commercial building.

A nature walk in the south lot represents the plants found in the Sonoran Desert, and brings pollinator species to the Plaza site.

Vegetation along adjacent creates a sense of place, letting visitors know they are in Ajo’s town center.

Shade structures line the center of the park and echo the rows of palms around them.

Ajo Regional School

al rci

g

Bld

me

Mixed-use pedestrian walks

N

m Co

Shade structures C

Artist gallery

C’

Shade trees to Curley School

l cia

Shaded path

g

Bld

er

m om

Traffic light

PV shaded parking

SC

Concept Drawing Parking

Vegetation

Curley School

Nature walk

Pedestrian Area Traffic Circulation

100’

Shade

Section C-C’: Vegetated swales on Route 85 serve several functions: slowing cars and making pedestrian crossing safer; capturing rainwater draining toward Plaza intersection during storms; and helping to reduce the heat-island effect around the Plaza.

C Not for construction. This drawing is part of a student project and is not based on a legal survey.

Catholic Church

Route 85

Swale

NTS

Route 85

Plaza park

C’

Melissa Carll, Héloïse Chandless | The Conway School

Traffic turns into the Plaza at the light, and drives across the mixed-use pedestrian walk, or enters the Plaza along the tree-lined back street.

New parking area

The interior of the south commercial building is opened to make an intimate, shaded commercial area (housing live/work/retail units), which also serves as a cool and enjoyable shopping space and a shaded connection between the south lot parking area and Plaza park.

Prepared for ISDA and PNIP

Alternative C looks to draw in people from outside Ajo, while still maintaining a community feel to the Plaza property.

Solar panels create shaded parking areas for RVs and cars in the south lot, and generate energy for the site.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Overview

Alternative C: a Break through

Alternative C: A Break Through

17 /26

Alternative C: Details

Alternative C: Details Pedestrian Crosswalk and Outdoor Eating Space

PROS

CONS

• A shaded path connects the south lot and Plaza.

• Solar panels shade parking.

• Improved pedestrian access between the park and south lot with building cut-through.

• Nature walk showcases vegetation of the Sonoran Desert.

• Vegetative swales slow traffic and capture rainwater runoff.

• Indoor commercial space may impact the historic designation of the buildings.

C

Outdoor eating area

Shade: Parasols

Vegetated swale Shade parasols Native planting

Vegetated median

Broad pedestrian walk ial

Traffic Light

rc me

S

m Co

g Bld

Live/work/ retail units

Shade structures can be single units, modular or linear. The proposed shade structures for the park resemble parasols that mimic the appearance of the palm trees.

Melissa Carll, Héloïse Chandless | The Conway School

N

Prepared for ISDA and PNIP

erc

m om

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Broad raised pedestrian crosswalks connect commerce to park, and serve as places for umbrella-covered tables. The seats, out from under the arcade, look appealing to people driving along Route 85.

ldg

B ial

Outdoor eating area

Not for construction. This drawing is part of a student project and is not based on a legal survey.

18 /26

Events, like the new Axis Art Walk (an art walk between the former depot and Curley School), are attractive because people can walk unimpeded by cars. The train depot at the end of the walk is a restaurant, serving Tohono O’odham food, samples of which are grown in

Concept Drawing

Alternative D moves outside of the Plaza property to explore how changes in the neighborhood surrounding the Plaza can positively impact the revitalization of the site.

Vegetation shades neighborhood sidewalks, and new parking lots for the Plaza use a vacant space adjacent to the south lot. Pedestrians are given priority in the park, and a strong visual and physical connection is made to the Curley School.

Ajo Regional School

al rci

Seating for resturant

g

Bld

me

N

Pedestrian only zone

m Co

Native culinary garden

Botanical garden ’

D

Shade trees to Curley School Vegetated swales

ial

rc me

D

om SC g Bld

Raised pedestrian crossing

Connection through commercial business PV panels shade park

Parking

Vegetation

Tree-shaded parking

RV parking

Curley School

Pedestrian Area Traffic Circulation

100’

Shade

Section D-D’: The Axis Art Walk incorporates Curley School artwork along a path following the historic town axis. After people stroll through an art show, they can enjoy dinner at the depot restaurant.

NTS

D’ Not for construction. This drawing is part of a student project and is not based on a legal survey.

To Curley School

Pedestrian crossing

Art walk

Bandstand

Art walk

D’

Melissa Carll, Héloïse Chandless | The Conway School

Pervious pavers along Plaza park reduce water pooling, and the former traffic lanes can be opened to cars when festivals occur, if extra parking is needed.

Tree-shaded parking

A cut through the warehouse to the back of the commercial space, allows people to walk from the south lot parking areas to the Plaza in airconditioning.

Prepared for ISDA and PNIP

A pedestrian-only Plaza is an attraction to town visitors and residents, alike.

a demonstration garden outside the restaurant.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Overview

Alternative D: Pedestrian Plaza

Alternative D: Pedestrian Plaza

19 /26

PROS

Alternative D: Details

Alternative D: Details

Perspective of Pedestrian Crosswalk Along Axis

CONS

• The Plaza is a pedestrian-only • Parking is situated farther from the commercial spaces. space.

• Pedestrian access is improved • Car circulation is limited w/building cut-through. and may reduce number • Axis art walk recognizes town of people who stop at the Plaza. history, and draws people through the Plaza.

• Pervious pavers reduce water pooling around the park.

• PV panels shade parking.

The physical connection from the Plaza to the Curley School is lined with pervious paving on pedestrian crossings, and shade trees in vegetated swales reduce water pooling at the intersection.

Seating for resturant r

l cia

me

Pedestrian only zone Botanical garden

Art walk

Vegetated swales

r

me

S

m Co

l cia

g

bld

Cars park outside of the central area. The trees that line the parking spots also shade sidewalks and serve part of ISDA’s food production goal. Solar panels shade parking areas in the south lot, and provide energy for the Plaza buildings.

Not for construction. This drawing is part of a student project and is not based on a legal survey.

Melissa Carll, Héloïse Chandless | The Conway School

Perspective of “Destination Ajo”

Prepared for ISDA and PNIP

N

m Co

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Restaurant

g

bld

20 /26

Newly developed stores

Outdoor eating patio Cultural center and restaurant

The southwest section of the park, surrounding the now-opened bandstand (A), is a pollinator garden (B), which grows flowering plants native to the Sonoran Desert.

N

The facades of the commercial buildings on Route 85 have been refitted as attractive, glass-fronted stores with colorful awnings, to draw the attention of traffic travelling along the road.

Not for construction. This drawing is part of a student project and is not based on a legal survey.

m Co

Food Stands

C Pollinator Garden

H

Vegetated Swales

F D

E A

B

Extended 15’ Sidewalk Crosswalk

J

Traffic light Newly developed stores

al

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I

ing

B

d uil

mm

o SC

s

nit

e

/R

rk Wo

lU tai

e/

Liv

60

Melissa Carll, Héloïse Chandless | The Conway School

Car traffic enters the Plaza at the light (I), and circles one-way around the park. Sixty parking spaces remain on the Plaza, and new crosswalks are added at the top of the park (J) to provide easier access to the Curley School.

Native culinary garden

me

The northeast portion of the park retains most of the lawn (E), though a 20’ walkway demarcates the town axis, and allows for the Axis Art Walk (F). The walkway is covered with beautiful shade sails that do not interrupt the historic view.

The historic depot is transformed into a restaurant and cultural center with an umbrella-shaded outdoor seating patio on the shady north side of the building (G). Land to the south of the restaurant entrance becomes a 400-square-foot culinary garden—its native food plants are served on the menu (H).

i

Bu

Prepared for ISDA and PNIP

A new 15’ sidewalk runs along the top of the park, providing a place for people to walk and for food stands (C) to set up. The sidewalk is extended to provide vegetated swales (D) to mitigate stormwater runoff from neighboring streets. The sidewalk reduces the width of the roadway so that passing motorists slow down, notice, and stop at the Plaza.

al rci

G

ng ldi

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

The final design details community and tourist components that are needed as part of a revitalized Ajo Plaza park, which is rehabilitated to meet the current needs of town residents and tourists alike.

Final Proposal: Destination Ajo

Final Proposal: Destination Ajo

21 /26

PV-shaded parking

The warehouse space is divided in two, and the walls are removed from the east end, creating a shaded community space and farmers market (L). The front of the business is enhanced with native vegetation, and three parallel parking spaces are added along Route 85 for convenience.

K

me

N

m Co

Ajo Regional School

P

ial

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Shade trees around town

S

Q Farmers market and community space

/

ork

w e/

ai ret

s

nit

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Liv

K

g Bld

L

K

K N

Curley School

M

J

O

PV-shaded RV parking Pomegranate trees Garden center Community garden

Melissa Carll, Héloïse Chandless | The Conway School

Along the historic district neighborhood streets, running out from the park, trees offer fruit and seeds in season and shade streets for a walkable neighborhood (Q).

g

Bld

Prepared for ISDA and PNIP

The final proposal looks outside of the Plaza property to show that changes effected off-site can impact the Plaza positively. A boardwalk runs over the railroad tracks and wash to connect to the regional school (P).

Education about Tohono O’odham “ak-chin” farming takes place in the wash with school groups and ISDA programs.

al rci

ng mi far tion hin tra -C ns Ak emo d

Part of the south lot is given over to community gardens and food production (M). The small building on the site (N) becomes the garden center, selling supplies to residents and native plant and seed information to tourists. It also houses the tools needed for the garden plots. Pomegranate trees shade the 20’ gathering space in the center (O).

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

New parking, shaded by PV-bearing structures, are sited to the northeast of the cultural center and restaurant. Further parking areas in the south lot are covered with solar panels (K), which provide energy to businesses on the Plaza property. Excess energy is sold to the grid.

Final Proposal: Destination Ajo

Final Proposal: Destination Ajo

200’

Not for construction. This drawing is part of a student project and is not based on a legal survey.

22 /26

Final Proposal:Details

Final Proposal: Details

PV panels provide shade for five car spaces, and three RV parking spots. The panels provide energy for the business located inside the warehouse.

Cars traveling north on Route 85 are greeted with tree-lined streets and views of the community gardens along the formerly vacant south lot.

Not for construction. This drawing is part of a student project and is not based on a legal survey.

Melissa Carll, Héloïse Chandless | The Conway School

Left: The 15’ sidewalk along the top of the Plaza is a place for food stands and outdoor eating spaces, which prompt people to stop in the Plaza. Vegetated swales on the sidewalk help prevent water pooling at the intersection.

Prepared for ISDA and PNIP

Shade sails highlight the walk along the axis, but do not block the view between the Curley School and the former train depot-now-Tohono O’odham foods restaurant.

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

The traffic median in front of the new restaurant is opened along the axis line to draw people through the space. Curb cuts on the median allow runoff to water the native vegetation.

23 /26

Vegetated swales and curb cuts can:

• Reduce stormwater runoff • Slow runoff, prevent erosion, and filter sediment.

• Take up pollutants that contaminate street runoff • Reduce urban heat island effect by increasing plant transpiration and lowering temperature on roads and sidewalks.

3. Heat island effect Heat islands occur in all cities, as surfaces such as roofs, windows and sidewalks absorb the heat from the sun. It can be mitigated by planting trees to shade buildings and by using light-colored materials for roofs, sidewalks and street paving. This provides the benefits of: • Cooler houses, requiring less airconditioning • Cooler streets for walking and cycling Not for construction. This drawing is part of a student project and is not based on a legal survey

requirements. The green roofs also cool the PVs, which increases their efficiency.

Appendix A: Green Infrastructure

• Collecting street runoff that pools around the Plaza park on Route 85 will require an underground cistern, which may cost upwards of $80,000.

• Building runoff from the south commercial building could be collected in upright, exposed tanks. The cost could be upwards • PVs on the roofs would generate of $25,000, providing around 250,000 approximately 93,300 KWH/month. Excess gallons of water, or 10% of the park’s energy can be sold back to the grid.

Above and right: annual water requirement.

• PV structures shade the roofs of the Vegetated swales can be Flush curb buildings and reduce air-conditioning placed on the extended A study evaluating the costs and benefits of 15’ sidewalk along the top requirements.

Street level installing rainwater harvesting systems will be of the Plaza. Trees planted • Visible structures can serve as examples required before proceeding.

Set riprap 2” there will help shade the to residents, encouraging them to adopt below curb street, and catch runoff 4”-8” riprap on 2. Green infrastructure solar energy. from the neighborhood slope only Vegetated swales and curb cuts are two • Year-round hot water can be provided by Detail:Vegetated Swale streets around the Plaza. types of green infrastructure that can solar water heaters on the roof. be implemented around the site. Green 5. Green roof and facades infrastructure along neighborhood streets Roofs and facades with vegetation increases outside the Plaza property can help reduce Curb Cut thermal mass, and lowers the temperature water pooling on the site.

Curb cuts along roadways help reduce runoff. The cuts in of buildings, reducing air-conditioning

2” Tree planting shelf Water level Existing curb cut

the curb allow water flowing down a street to infiltrate into a vegetated basin, and water the native plants.

6. Greywater harvesting A study of the grey water harvesting potential of the Plaza site would establish whether the park irrigation requirement could be A min. 6’ wide area between curb and sidewalk is needed met by this resource.

Trees and water-sensitive plants are placed on terraces above level of regular inundation.

(this allows 1.5’ of level bottom 8” below street level; width can be 5’ min. if there is no on-street parking).

Sidewalks/pedestrian paths slope 1% toward basin.

18” flat wide step-out zone between inside of curb and rock edge allows people to step out of their cars onto a flat surface; slope 1% toward basin to collect rainfall (this zone can be reduced to 6” at sites without adjacent parking).

12” flat safety zone between sidewalk/pedestrian pathways and rock edge; slope 1% toward basin to collect rainfall.

All slopes greater than 33% are protected by 8”-16” set-in rock.

Curb cut inlet lined with 4”-8” rock to reduce erosion.

18”-24” wide curb cut with 45-degree sloped sides; serves as both the inlet and outlet of basin.

Area of level bottom is maximized to increase stormwater infiltration.

stormwater runoff Information from the Watershed Management Group

Melissa Carll, Héloïse Chandless | The Conway School

Vegetated Swales

4. Solar energy Ajo is ideally located to harvest the sun’s energy. The building roofs could be fitted photovoltaic (PV) and solar hot water collectors. An engineer should assess the structural integrity of the buildings. Shade structures mounted with PVs could generate electricity as they provide shade for parking and walkways. Solar incentives: www. arizonagoessolar.org/Utitlity/Incentives/ AjoImprovementCompany.aspx

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

1. Rainwater harvesting The Plaza park lawn is currently irrigated using untreated water town water. Initial investigation suggest that the cost/benefit ratio is not favorable.

Prepared for ISDA and PNIP

Appendix a: Green Infrastructure

24 /26

Desert palm

Planting Plan The date and desert palms that line the Plaza park were part of the historic planting plan for the site. Since the trees are nearing the end of their life, a phased substitution plan for the palms will allow ISDA to replace the trees and maintain the historic appearance and integrity of the park.

Date palm

Jacaranda

To be considered: • The date palms are currently almost the only source of shade in this outdoor space.

• The other source of shade is the African sumac, an invasive.

• The town does not wish to substitute or eliminate any of the lawn.

• The original, formal planting of the park is to be respected.

African sumac

Oleander

Phased Substitution Plan

Phase 1: Replace the Alternate Desert Palms Along the Perimeter Replace every other desert palm along the perimeter of the park. Second, remove the existing shade trees between the desert palms: invasive African sumac and poisonous oleander.

Replant them with flowering desert willow and mexican ebony as the new shade trees.

Phase 1: New Desert Palms

Phase 1: New Shade Trees

Phase 2: Replace the Remaining Desert Palms As the new desert palms establish themselves, replace the remaining grown desert palms.

Phase 2: Replace Remaining Desert Palms

Phase 2: Replace the Date Palms As soon as the shade trees and desert palms become established (this may take up to ten years), the date palms can be removed and substituted with the same species.

Phase 3: New Date Palms

50’ Not for construction. This drawing is part of a student project and is not based on a legal survey.

Melissa Carll, Héloïse Chandless | The Conway School

50’

Prepared for ISDA and PNIP

The plan falls into two phases. The phases focus on maintaining the vertical aesthetic of the park and the shade that is currently available:

Appendix B: Palm Substitution

Existing Vegetation Around the Park

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

Appendix B: palm substitution

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Southern Arizona Rain Garden Plant Adaptation for Water Harvesting Earthworks - researched and classified by Russ B

X X X X X X X X X X X X X

X

X X X X X X X

X X

X

X

X X X X X X X

X X X X X X X X

X X X X X x X

X X

X X X X X X X X

X

X X X X X

X

7" 1'-2' 4" 4' 3' 3' 2' 1'

7" 6"-1' 1.5" 4' 3' 3' 2' 1'

Sp, S Sp, S S Sp Sp, S S, F Sp, F Sp, S, F

blooms a lot, weedy, easily controlled, nectar source X short lived perennial spring wildflower- reseeds large white flowers, nocturnal pollinator hummingbird plant hummingbird plant, start blooming in Feb. summer root perennial w/ bright yellow flowers, used for basket weaving great winter-spring bloomer w/ lilac flowers wonderful everblooming groundcover

X X X X X X X

15'-20' 15' 20' 20'-30' 30'-40' 15'-20' 20'-30'

15'-20' 10' 20-35' 20'-30' 30'-40' 10'-15' 15'-20'

Sp, F S Sp Sp

Native to Texas, does well in arid clime, beautiful flowers great butterfly food source, landscape tree white flowers, attracts bees, minimal pruning one of the best native shade trees, edible seeds tough native tree, beautiful wood, bf food, human food purple flowers in summer small oak to 15'

X X X X X X X

…

food for pipevine swallowtail butterfly, poisonous twining perennial vine bright yellow flower followed by red winged fruit hummingbird plant wild tepary bean, food source, bf wild desert bean,excellent rabbit food, bf summer root perennial small vine

X

X X X X

X

X X

X

X X X X X X X

X X

X

X X

X X X

X X

Special Cultural

Sp, S, F …

Sp, S, F

X

X X X X

Other Wildlife Use

… … … … … … …

X

X X X

Cover

3' 6"-15' 10' 8' 1'-1.5' 12' 10'

X

X

X

Hummingbird

good choice for residential, 1-3 feet at maturity spring blooming perennial wildflower

X

X

X X X X X X X X X X X X X X X X X X X X X X X X

Butterfly

1.5' …

S

X X

X X

Wildlife Plant

1.5' 6"-1'

5' 6' 4' 1'-3' 4'-5' 8'

X

X X X X X X X X X X X X X X X X X X X X

Highly Allergenic

12' 6'-8' 2'-3' 4' 2' 5' 3' 4' 5'-6' 3'-4'

drought tolerant, apricot blossoms, warm microclimate great butterfly and bee plant open form bush hummingbird plant great butterfly plant, but aphids like this plant hummingbird and butterfly plant native hot pepper spring blooming bush needs good drainage pink and yellow pealike flowers in warm season butterfly plant blooms fall-spring food for desert tortoise hummingbird plant hummingbird plant attracts cardinals and pyroloxias hummingbird shrub, frost damage in cold years orange fl true indigo, frost sensitive, reseeds yellow flowering shrub, very fussy, north exposures only good wildlife plant kills out with long standing water, but reseeds deciduous shrub w/ edible berries larval food for sulfur butterflies available in many colors covered with yellow flower heads in spring easy, tough plant

Invasive, weedy

Sp, S, F S, F Sp, S

Ample

3'-10' 4' 6'-8' 4'-6' 2'-4' 1'-3'

Moderate

Minimal

4'-8' 1'-4' 8'-10' 4'-6' 2'-4' 1'-3' 3' 5' 6' 4' 1'-3' 4'-5' 10' 8' 3'-10' 2'-4' 3'-4' 6' 2' 4' 2' 2' 3' 2'-3'

X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X

X X

X

X X X X X X X

X X X X X X X X X X X X X X X X X X

X

X

X X X X X X X X

X

X X

X X

X X X X X X

X X X X

X

X

X X X X

X X

Appendix C: Plant Palette

X X

NOTES

X

X X

X X X X X X X X X X X X X X X X X X X X X X X X X

X X X X X

Melissa Carll, Héloïse Chandless | The Conway School

X X

Bloom

Prepared for ISDA and PNIP

X

Spread

Revitalization of the Ajo Plaza | Ajo, AZ | Spring 2011

X X X X X

Height

Special Use/Restrictions

Plant palette inspired by Brad Lancaster, Rainwater Harvesting

X

Water Usage once Established

None

Desert Willow Kidneywood Mexican Ebony Desert Ironwood Velvet Mesquite Smoke Tree Toumey Oak

Root Succulent

TREES Chilopsis linearis Eysenhardtia orthocarpa Harvardia mexicana Olneya tesota Prosopis velutina Psorothamnus spinosus Quercus toumeyi

Stem Succulent

Dogweed Western Wallflower Tufted Evening Primrose Scarlet Bugler Parry Penstemon Wild Devil's Claw Goodding's Verbena Desert Zinnia

Rosette Succulent

HERBACEOUS Dyssodia pentachaeta Erysimum capitatum Oenothera caespitosa Penstemon barbatus Penstemon parryi Proboscidea altheafolia Verbena gooddingii Zinnia acerosa

Bulb

Desert Pipevine Pink Morning Glory Samara Vine Snapdragon Vine Wild Tepary Bean Desert Wild Bean Tumamoc Globeberry

Growth

Perrennial

VINES Aristolochia watsonii Convolvulus incanus Janusia gracilis Maurandya antirrhiniflora Phaseolus acutifolius Phaseolus filiformis Tumamoca macdougalii

Annual

Desert Agave Desert Anemone

Deciduous

SUCCULENT Agave deserti simplex Anemone tuberosa

Evergreen

X X X X X X X X X X X X X X X X X X X X X X X X

Succulent

Shrub

Indian Mallow Prairie Acacia Viscid Acacia Desert Honeysuckle Desert Milkweed Native Fairy Duster Chiltepin Bladder Bush Baby Bonnets Indigo Bush Wild Buckwheat Southwest Coral Bean Ocotillo Arizona Wild Cotton Desert Lavender Indigo Bush Penstemon Parish Wolfberry Rough Menodora Squawbush Desert Senna Globemallow Trixis Devil's River'

Vine

COMMON NAME

Tree

BOTANICAL NAME SHRUBS Abutilon palmeri Acacia angustissima Acacia neovernicosa Anisacanthus thurberi Asclepia subulata Calliandra eriophylla Capsicum annuum Cleome isomeris Coursetia glandulosa Dalea pulchra Eriogonum fasciculatum Erythrina flabelliformis Fouquieria splendens Gossypium thurberi Hyptis emoryi Indigofera suffruticosa Keckiella antirrhinoides Lycium parishii Menodora scabra Rhus trilobata Senna covesii Sphaeralcea ambigua Trixis californica Zexmenia hispida

Herbaceous

Plant Type

The following plants are suitable for the vegetated swales, the south lot, or any green infrastructure.

Songbirds/ Native Birds

appendix C: Plant palette

26 /26

acknowledgements The Conway team would like to thankTracy Taft, Nick Francis, Mimi Phillips, and Jim Wilcox, International Sonoran Desert Alliance Gary Bachman and Danny Tylutki, Pima Neighborhood Investment Partnership Richard Fe Tom, principal of the Architecture Company Volunteers at Organ Pipe National Monument and Cabeza Prieta National Wildlife Refuge