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PACHACAMAC SANCTUARY

HOW DO YOU BUILD A PARK IN A COASTAL DESERT LANDSCAPE
THREATENED BY FORCES OF NATURE AND MANKIND
PRESERVING CENTURIES OF HISTORICAL ARTIFACTS BENEATH THE GROUND?  
 
The terrain of the Pachacamac sanctuary. You can notice the trails of human movement and erosion caused by coastal wind.
Copyright 2017-Marcela Durand

CREATE A PLINTH AND A MANTLE

A landscape innovation that turns ecology and urban growth as the main drivers to protect archaeology.
Kaukari Park, Chile by Teodoro Fernández
THE PLINTH
is an active urban promenade that limits the Pachacamac site, protecting it from urban sprawl, but also plugin into the existing fabric to activate several neglected public spaces. The plinth acts as a “water factory,” collecting and treating grey water from the neighborhood and re-using it to irrigate the park.
Lomas de Ancón, Lima. Photo by José Mamani
THE MANTLE
is an ecological blanket that covers the entire site, protecting archaeological remains from the forces of nature, while providing ecosystem services to the surrounding neighborhoods. It acts as a “fog factory,” moving recycled water through the park and turning it into fog to create a “tillandsial,” a typical Peruvian coastal desert ecosystem.
A resilient urban balcony for the community to experience the park.
A soft blanket of plants without roots to protect the site from erosion.

DESIGN STRATEGIES

The park is conceived as a narrow urban plinth which plugs into the existing fabric surrounding the open space and protects the archaeological relics in the sanctuary.
Using biofiltration techniques to treat the water from surrounding neighborhoods, we propose to use fog sprayers to conserve water while irrigating this arid landscape 
Taking clues from historical walls designed by Incas, multiple loops and transit modes are designed around and into the sanctuary allowing both locals and tourists to experience the archaeology.
PLUG-IN
URBAN PLINTH
WATER-WISE
PACHACAMAC LOOPS
A challenge like this needed stronger strategies which can adapt over time to the needs of the sanctuary and community. These ideas can also be applied to similar contexts for landscape projects in other parts of Lima

INNOVATION

IRRIGATION
CHANNELS
DECENTRALIZED WATER TREATMENT
FOGWALKS
The fog walks are economically prototyped movable boardwalks which transport water and people to deeper parts of the sanctuary. Built-in fog-sprayers will turn water into fog to irrigate this new ecosystem.
In Pachacamac the problem of urban sprawl becomes the solution to water the park. We propose a network of small scale underground treatment tanks to recycle the neighborhood´s wastewater.
We propose to bring recycled water to the sanctuary storage ponds and move it along the perimeter in narrow/deep acequias which irrigates all the plantation on the plinth.
A problem brings an opportunity and a difficult problem brings an innovation. To transform the arid landscape of Pachacamac into a lush park we propose 3 innovative water strategies to recycle, irrigate, and move water.

THE PLINTH

The plinth is a narrow promenade and buffer which largely occupies the perimeter of the intangible zone. The promenade skirts along the edge of existing houses with a bus loop road and often plugs into the existing open spaces in the community providing active areas for recreation. It establishes a continuous path and street to improve access, connectivity and amenities for both- residents and visitors while securing the park’s perimeter from undesired land invasion. The goal is to create an urban balcony over the intangible zone to contemplate its vastness instead of creating an opaque barrier.

 

This promenade has two main stretches. In the northern limit the Urban Plinth houses the new Pachacamac Esplanade; an urban scale plaza, a Community Market, a ceremonial flag post, the northern multi-modal hub, the visitor center, a dry nursery and a wide East-West walk that frames the north entrance to the Park. To further activate this esplanade, we propose to transform the existing bus parking into a functional multi-modal hub for easy interchange between urban buses and private vehicles.

 

In the south, the Archeological Plinth connects the entrances of the Site Museum and MUNA. This promenade articulates a sequence of shaded areas, plantations and esplanades that connect both sides of the former Pan-American Highway. In this area, complementing the existing program we propose a new access to the park plus the administration building, a pedestrian bridge in front of the Site Museum, an overlook to the wetland area, the southern multi-modal hub and a parking area for visitors. Next to them a tensile structure provides shade to the Pachacamac Crafts Market oriented mainly to the visitors of the ruins and MUNA.

 

The other stretches along the Plinth is an active public promenade which allows to tour the site at its periphery. This edge varies in width adapting to different site conditions, providing a wide array of open spaces, sports facilities, multi-purpose pavilions, and shade structures for the neighboring communities to enjoy. Every 250m intervals, there will be bathrooms and surveillance stations that will ensure a convenient and safe use of these public spaces.

The Plinth is proposed as a thin edge intervention that intends to modify the existing topography as little as possible in order to create a legible boundary for the Sanctuary. In this regard a minimum leveling is proposed to avoid bringing outside material. In places where the plinth’s width requires it, prefab concrete elements plus traditional local stonewalls will be used to extend this platform out into the park. In other places where topography does not allow for a clear height difference to act as a barrier, we propose several typologies that adapt to these situations.

THE MANTLE

Just as The Plinth protects the Sanctuary from human interventions, The Ecological Mantle is a living blanket that protects archaeology from the forces of nature. We propose to create three distinct landscape strategies to grow vegetation inside the park area

Tillandsial Fog Park of Pachacamac

The “tilandsiales” are ecosystems found in the coastal desert of Peru and Chile. These plant formations are mainly monogeneric, composed almost entirely by one or more species of the genus Tillandsia. Despite the extreme aridity of the desert, the “tilandsiales” are permanent ecosystems that survive thanks to the coastal fog. These species have morphological and physiological adaptations to survive in the desert, such as the presence of compound hairs and the ability to use CAM, and C3 photosynthesis. In the “tilandsiales”, populations of these species follow a growth pattern in bands which is determined by the slope and amount of fog that they receive. Epiphytes like Tillandsia landbeckii, Tillandsia latifolia, and Tillandsia straminea will be used in the Mantle because they do not have roots. Therefore, they can cover large extensions of land without affecting the subsoil. Their capacity to accumulate sand over time will allow to keep the archaeological remains safe for future generations. This proposal aims to recover a unique Peruvian ecosystem in the Sanctuary area, ​​protecting the subsoil of anthropogenic activities while helping to stop the erosion caused by the wind. This new Fog Park will underline Lima’s coastal character, increasing the contribution of fog, irrigating the Tillandsial in a non-invasive way and accentuating the unique environmental character of the Sanctuary.

Educational Orchards

A primary goal of this project is to integrate the community both as users and stewards of the park. Fruit tree orchards located near park access points will be used to teach the community about desert agriculture and innovative plantation techniques in arid climates. Taking back home the fruit of species such as Mangoes (Mango Indica), Chirimoyo (Annona cherimola), citrus lemon x lemon, citrus orange trees x sinensis, and Moreras (Morus alba), will help people acknowledge the scale and ingenuity of this innovative effort to bring desert back to life.

 

Tamarugal Reforestation

We propose to cover the perimeter of the Ecological Mantle with a 20 x 20m grid plantation of Prosopis tamarugo and Tara spinosa. These species have tap roots that can reach deep aquifers making them highly drought tolerant. This plantation will allow to reduce the soil temperature and will act as a windbreak for the plinth and its promenade. Previous experiments such as the Chilean Pampa del Tamarugal, are a living proof of the success of a regional scale reforestation in one of the most arid landscapes in the world.