Calexico Urban Planning Feasibility StudyCALEXICO URBAN PLANNING FEASIBILITY STUDYCOST ESTIMATE DRAWINGS 03-22-2016

UNITED STATESMEXICIO

CALEXICO, CA

PROJECT LOCATION

WALL MOUNTED LIGHTINGLIGHTOPIA CLESSIDRA LEDOUTDOOR WALL SCONCE

BENCHVECTOR SEATING SYSTEM

PEDESTRIAN LIGHTINGALCOTT FORMS

TRASH RECEPTACLEFORMS+SURFACES KNIGHT

PLANK PAVINGPROMENADE

PERVIOUS PAVING

PLANTER ROCK

SHADE STRUCTURE FABRICPALO VERDE TREES AGAVE

DESERT GRASSES

MAGENTA AND ORANGEBOUGAINVILLEA

XERISCAPE

Aloe

Palo verde

Plank paving

Shade structure fabric

Queen’s wreath

General Services Administration GS-09P-15-KT-D-0009 May 5, 2016

Downtown Calexico acts as the focal point of the city and its commerce. In addition to providing a welcoming, safe, and family orient-ed gathering place, it also reflects the cultural character of this southern border community. Recent developments in the area include a proposed design for a new downtown transit center on Third Street and Rockwood, renovation of the existing pedestrian border crossing, and a new vehicular Land Port of Entry that will re-route traffic away from downtown, pose an economic opportunity for the merchants in the area.

This booklet includes a feasibility study that focuses on relocating a power transmission line that has been displaced from the con-struction of the new Land Port of Entry from overhead to underground in addition to creating a vision for improving public spaces and the streets of downtown Calexico. This vision includes two primary design concepts and one lighting concept: Retreat, Revive, and Relight.

Introduction

1. Introduction2. Retreat design concept3. Revive design concept4. Streetscape interventions overview5. Landscape and materials6. Bloom schedule7. Phasing8. Electrical routing

Contents

Downtown Calexico is busy, vibrant, and full of people. Most buildings are one or two stories with frontage on the sidewalk and distinctive porticos and arcades covering the sidewalks. The Retreat concept builds on the existing arcades as a place to retreat from the sun, yet still celebrating the abundant natural light. Furthermore, the pedestrian border crossing is located on First Street and is a major source of pedestrian traffic into the center of downtown. Typically people cross the border and walk north on Rockwood, pass-ing First, Second and Third Street. Second Street is densely populated with a large variety of stores and businesses and therefore it was chosen for the Retreat design concept. Retreat boasts a welcoming, vibrant, distinct, and signature look for Second Street by celebrating rhythmic patterns of dappled light, shade, color, and vegetation.

The Retreat design concept moves the existing angled parking from the curb line to the center of the street. There is a 2-foot xeri-scape planter along the curb lines that includes a combination of smooth stones, desert grasses, and a variety of colorful blooming plants. 11-foot travel lanes, angled parking each direction and a 4-foot pedestrian pathway are located at the center of the street and between the parked cars. The pedestrian pathway, mid-block crossing, and corner-block crossings are paved with decorative perme-able linear plank paving that relate to the new Land Port of Entry paving and establish safe and convenient pedestrian connections. The center angled parking area is also permeable paving and arranged in a herring bone pattern, distinguishing parking and pedestri-an areas.

Contemporary, colorful, and distinctive structures and trees provide ample shade for parked cars and help to decrease solar heat gain. The structures’ shade material could be fabric, metal panels, or metal mesh and the supporting structures could take on many forms including cantilevered roofs or fabric stretched between poles. This center parking layout creates a distinctive look to the street-scape and has the potential to be closed occasionally in the future for events such as farmers markets or street fairs, with vendor tents located down the vibrantly shaded center of the street.

Retreat integrates flowering desert vines with the shade structure design in addition to pockets of xeriscape in the parking area that in-cludes smooth stones that relate to the shape of the existing arcades that line the streetscape, colorful succulents or flowering plants, and agave which is celebrated in the new Land Port of Entry design. Retreat transforms the existing stark streetscape into a lively and vibrant place to shop, relax, meet friends, and enjoy the day.

Retreat

The Revive design concept is a more minimal intervention then the Retreat design concept in exchange for more flexibility and adapt-ability. While the width of Second Street is able to accommodate parking in the center of the street, First and Third Street can not because of street width. Furthermore, First Street is adjacent to the pedestrian Land Port of Entry and has one-way traffic and Third Street is adjacent to the site for the new transportation center and is narrow. Revive introduces intermittent projecting curbs and tree planters in addition to a midblock crossing that reduces the size of the block to a more human scale and produces a traffic calming effect that improves pedestrian safety by increasing pedestrian visibility, shortening crossing distances, slowing turning vehicles, and visually narrowing the roadway.

The Revive design concept alters the sidewalk at the corners and midblock by extending out the depth of the existing parking stalls. The midblock extensions use three parking stalls on each side of the street and are connected by a midblock crosswalk with decora-tive paving to match the extensions. The paving for the new mid-block crossing and corner crossing are linear in pattern, also relating to the new Land Port of Entry design. The extensions provide room for additional amenities in addition to creating a shorter walking distance for pedestrians and making them more visible to drivers as they wait to cross the street. 75-feet is the most anyone has to walk to use a street crossing.

The sidewalk extensions also provide room for tree planters, pedestrian lighting, benches, trash cans or other site furnishing, and stone and desert plant xeriscape. The xeriscape design includes smooth stones that relate to the existing arcades that line the street-scape, colorful succulents or flowering plants, and agave which is celebrated in the new Land Port of Entry design. The vegetated curb extensions are also contribute to storm water management by filtering storm water runoff and utilizing infiltration and evapotrans-piration.

One of the most distinct characteristics of Revive is the rhythmic planting of trees along the block. Once seen as highly problematic for many reasons, street trees are proving to be a great value to people living, working, shopping, sharing, walking and motoring in and through urban places. Not only do trees bring life and beauty the street, but they also positively affect the microclimate by providing filtered shade and a cooling effect from natural transpiration. In the wintertime, deciduous trees that are low-water-use and native to the desert such as Palo Verdes, Ironwoods, and Texas Mountain Laurel loose their leaves and allow more sunlight to pass through their canopy. Ultimately Revive brings life, beauty, and safety to existing downtown Calexico streets with minimal intervention.

Revive

The Relight design concept includes installing pedestrian wall-mounted lighting and roadway lighting along Rockwood, between First and Third Street. Rockwood is the main north-south route that pedestrians use after crossing the Land Port of Entry. Currently this portion of Rockwood is very dimly lit at night, providing only two street lights along the entire stretch of the street.

Street lighting is a key streetscape element that defines the quality of the nighttime visual environment in urban settings and safety. The quality of visual information is critical for both traffic safety and pedestrian safety and security. Relight provides lighting that is designed not only for vehicular traffic on the roadways, but also parking and pedestrians on sidewalks and paths.

Similar to the rest of the Calexico downtown area, the arcades and porticos that line Rockwood extend to the sidewalk, leaving only a few locations for street lights. Relight provides two street light poles at every intersection and one midblock, at the alley. Each pole has two lights; one that illuminates the street and one that illuminates the sidewalk. Various lights, signs, banners, and other decora-tive items can be mounted to them, defining the visual characteristic of the downtown area during daylight hours.

Relight provides eight wall-mounted grazing lights per each block on Rockwood that illuminate the pedestrian sidewalk and the wall surface by dramatically accentuating the texture of a wall. These types of lights are mounted very close to the plane of the wall and the light projects obliquely across surface as a high-intensity light with a relatively narrow beam angle. The wall grazing fixtures are intended to reveal the texture, shape, and character of the wall along Rockwood while providing visual interest and rhythm as cars and pedestrians travel along the street.

Today street lighting commonly uses high-intensity discharge lamps, often high pressure sodium lamps (HPS). Such lamps provide the greatest amount of illumination for the least consumption of electricity. New street lighting technologies, such as induction or LED lights, emit a white light that provides high levels of lumens and allows street lights with even lower wattages. Relight fixtures could either be HPS or LED and it is recommended to use HPS if the existing fixtures will be maintained and LED if the existing fixtures will be replaced.

Relight

Streetscape Interventions Overview

Pedestrian Land Port of Entry

Vehicular Land Port of Entry

First Street

Second Street

Third Street

Roc

kwoo

d

The overall streetscape interventions intent is to create a vision for improving the public spaces and city streets beyond the Land Port of Entry using the Retreat, Revive, and Relight design concepts and to connect the businesses of downtown Calexico with the new expanded public transportation opportunities. Retreat is applied to Second Street between Imperial and Mary to activate the main shopping area of downtown. Revive is applied to First and Second Street because they have space and traffic challenges in addition to conflicting construction from the new Land Port of Entry and transit center happening adjacent to them. Relight is applied to Rockwood, the main north-south street that connects the Land Port of Entry and new transportation center.

Transit center site

The inspiration for the landscape design for downtown Calexico takes its inspiration from the natural surrounding desert in combination with the desire to create a welcoming and vibrant space for residents and visitors. The current streetscape is severe and includes minimal vegetation and wide swaths of pavement that can encourage fast driving. The climate is hot and dry, and that is why many of the sidewalks are shaded by arcades and porticos that project from the building facades.

Among the Retreat and Revive design concepts, shade is proposed as either trees, man-made structures, or both. Several desert tree options include Palo Verdes, ironwoods, and Texas mountain laurel. These desert trees can survive on minimal water and provide filtered shade and a cooling effect from their natural transpiration. They periodically go deciduous in the winter when more sunlight is desired and would require fairly frequent maintenance.

Shade structures lack the natural ambiance of plants, but also require less maintenance and offer consistent year-round shade coverage while providing the opportunity to introduce large swaths of vibrant color in to the streetscape. The presence of shade structures are also softened by incorporating flowering vines such as Bougainvillea and Queen’s Wreath. The shade panels could be fabric, metal mesh, or solid metal, each material offering a different look and feel along with varying densities of shade. The proposed palette of shrubs for the streetscape would also be low-water-use native and desert-adapted plants. There are many to select from that would offer an interesting variety of sizes, textures, and blooming colors and times.

Any vegetation would need to be irrigated with a drip system. While low-water-using, desert plants can not survive on only the small amount of precipitation that falls within their planter. A drip system is the most efficient way of getting the most water to the plants and not losing it to evaporation along the way. In conjunction with moisture sensors, rain gauges, and similar equipment, the drip system can be tightly operated to only irrigate when it’s needed.

Paving materials for crosswalks, pedestrian walkways, and parking stalls are permeable paving to help reduce heat gain with the added benefit of decreasing run-off into the storm drain system. There are contrasting materials to demarcate the pedestrian zones from the automobile zones. Planters are finished off with a rock material that provides a subtle accent and also offers dust control.

Site furnishings, including benches, trash cans, and information kiosks, provide streetscape with an outdoor room appeal. Frequently located benches and bench groupings provide the opportunity for people pause and visit; information kiosks could share news about upcoming events and sales.

Lighting is also a crucial element of a streetscape. Lighting fixtures create a strong vertical rhythm down the street during the day and a welcom-ing glow during the night. Area street lights, pedestrian scale pole lights, wall sconces, and tree up and down lights are all part of the lighting palette.

Landscape and Materials

Palo Verde

TX Mountain Laurel

Queen’s Wreath

Baja Passion Vine

Gopher Plant

Dawe’s Aloe Penstemon Mexican Sunflower

Verbena

Chaparral SageYarrow

Cosmo

Zinnia

Blackfoot Daisy

Fabric

Weathering steel

Painted steel

Powder coated steel

Permeable plank paving

Smooth rocks

Permeable herring bone paving Wall mounted lighting

Pedestrian lighting

Wall mounted lightingTrash receptacle

Modular bench seating

october

september

august

july

june

may

april

march

february

january

december

november

baja

pas

sion

vin

e

yarr

ow

verb

ena

daw

e’s

aloe

chap

arra

l sag

e

pens

tem

on

mex

ican

sun

flow

er

zinn

ia

cosm

o

blue

pal

o ve

rde

blac

kfoo

t dai

sy

shru

bs

vine

s

succ

ulen

ts

trees

quee

n’s

wre

ath

goph

er p

lant

tx m

ount

ain

laur

el

Bloom Schedule

october

september

august

july

june

may

april

march

february

january

december

november

baja

pas

sion

vin

e

yarr

ow

verb

ena

daw

e’s

aloe

chap

arra

l sag

e

pens

tem

on

mex

ican

sun

flow

er

zinn

ia

cosm

o

blue

pal

o ve

rde

blac

kfoo

t dai

sy

shru

bs

vine

s

succ

ulen

ts

trees

quee

n’s

wre

ath

goph

er p

lant

tx m

ount

ain

laur

el

Both the Retreat and Revive design concepts utilize vegetation to add color and vibrancy to the streetscape. Desert adaptive plants with capa-bilities of surviving in full-sun exposure and minimal water requirements can be planted according to a bloom schedule. The bloom schedule generates a palette of vegetation that allows that vibrancy to be present year-round by identifying when desert adaptive plants are in full bloom annually. With the proper selection, color can be present in every season and provide a dynamic liveliness to downtown Calexico.

44

4

3

2

1B1A

1A

Phasing Overview

Second Street

Third Street

Roc

kwoo

d

Paul

in

Impe

rial

First Street

44

4

3

2

1B1A

1A

Phasing is suggested for this project for both funding feasibility and construction sequencing. The overall phasing of the project makes the improvements applied to the central area of Second Street, between Paulin and Heffernan, and Rockwood priority. These streets are at the core of downtown and have substantial pedestrian and vehicular traffic. Next priority is Third Street and First Street, respectively. The final phase of improvements extends Second Street to Imperial and Mary and extends Third Street to Imperial.

Hef

fern

an

Her

ber

Mar

y

1A

1B1A

3

Phase 1

Phase 3

Phase 1 includes 1A and 1B. 1A includes applying the Relight design concept to Rockwood between First and Third Street. The street lights on the southwest corner of First Street and Rockwood and also the intersection of Third Street and Rockwood are not a part of this phase because the curb improvements at those intersections will be installed at later phases. There are two existing fixtures at those intersections that should produce sufficient street light until they can be replaced. 1A also includes applying the Retreat design concept to Second Street between Paulin and Heffernan. 1B includes extending Retreat on Second Street to Mary. 1B can also occur during Phase 4 if funding is not immediately available.

Phase 3 includes applying the Revive design concept to First Street between Rockwood and Heffernan. Curb improvements will only happen on the east side of the intersection of First Street and Rockwood and also one new street light will be installed at northeast of that intersection. Parallel parking at south side of First Street will remain due to the width of the street.

Second Street

Third Street

First Street

Roc

kwoo

d

Paul

in

Impe

rial

Hef

fern

an

Her

ber

Mar

y

Second Street

Third Street

Second Street

Third Street

First Street

Roc

kwoo

d

Paul

in

Impe

rial

Hef

fern

an

Her

ber

Mar

y

Second Street

Third Street

1A

1B1A

3

44

4

Phase 2

Phase 4

Phase 2 includes applying the Revive design concept to Third Street between Paulin and Heffernan. The existing street light at the intersection of Third Street and Rockwood will be removed and two new street lights will be installed at that location according to the Relight design concept. Parallel parking at south side of Third Street will remain due to the width of the street.

Phase 4 is the last remaining phase that completes the downtown intervention and it includes extending the Revive design concept on Third Street to Imperial and extending the Retreat design concept on Second Street to Imperial and Mary. If phase 2A was not completed after 1A, it would happen in this phase.

2

Second Street

Third Street

First Street

Roc

kwoo

d

Paul

in

Impe

rial

Hef

fern

an

Her

ber

Mar

y

Second Street

Third Street

First Street

Roc

kwoo

d

Paul

in

Impe

rial

Hef

fern

an

Her

ber

Mar

y

Project Title

Sheet TitleScale

Sketch Number

Project Number

DateUtility Diagram

GSACalexico Feasability Study

268389

03/22/16 01

NTS

Electrical Routing

Project Title

Sheet TitleScale

Sketch Number

Project Number

DateUtility Diagram

GSACalexico Feasability Study

268389

03/22/16 01

NTS The three proposed underground line routes were studied and it was determined that selected route to install the underground electrical routes is along First Street. The trench cross section depicts the two medium voltage circuits in the same trench with three spare conduits. If one of the medium voltage cable circuit faults the other circuit in the same trench will have to pick up the whole load that the failed circuit was carrying.

T-splices are required within each of the traffic bearing manholes so that Imperial Irrigation District would be able to tap off from this location for any future loading. Transition steel poles will be 65 to 70 tall, and they are going to utilize a rebar cage below grade level so that each transition pole is self- supporting without any down guys.

Project Title

Sheet TitleScale

Sketch Number

Project Number

DateUtility Diagram

GSACalexico Feasability Study

268389

03/22/16 01

NTS

Permeable pavingXeriscape

Desert grass

Bench

Pedestrian lighting

Planter rock

Wall mounted lighting