INTRODUCTION

At the request of the District 10 government in Santa Cruz Bolivia, VOLO Engineering Group proposed a design solution to address seasonal flooding of Avenida Vallegrande. Stagnant water collects in two low spots (Problem Areas A and C) on Avenida Vallegrande and in portions of UV-108 (Problem Area B) as shown below. This project includes pavement, storm water drainage plans and construction specifications to address these issues.

HEALTH EFFECTS

Stagnant water caused by poor drainage is a breading ground for disease causing mosquitoes and bacteria. Diseases associated with stagnant water include dengue and malaria.

SOCIAL EFFECTS

During the rainy season from December to March, portions of Avenida Vallegrande become impassible leading to missed work and school.

EXISTING DRAINAGE:

The area surrounding AV can be divided up into two watersheds with the west watershed draining to the new 16.5 Radial canal. The east watershed drains to AV. However, the storm water draining to AV encounters several low spots (Problem Areas A and C) and cannot easily flow to 16.5 Radial canal or 4thRing Canal. A low point (Problem Area A) located 300 to 350 meters from the north end is the most problematic area. Additional problem areas include the low point 300 meters from the south end.

PROPOSED PROFILE

The proposed roadway profile was designed with a single high point draining the majority of the storm runoff to the 4thRing Canal. Pipes were designed to handle the storm runoff when the roadway reached its drainage capacity.

DESIGN OPTIONS

Multiple design options were considered to address the drainage problems in UV-108.

• Option1: Continuous grade concrete roadway with one high point
• Option 2: Concrete roadway following existing grade with drainage to 16.5 Radial Canal through paved side roads and underground pipes (2A) or under ground pipes without concrete paved road (2B)
• Option 3: Concrete roadway with single low point and additional drainage culvert flowing to 4thRing Canal

RECOMMENDATIONS

The roadway and drainage improvements should be completed using Design Option 1 based on cost and reliability to prevent flooding. The following should be implemented to improve the system and address constructability and effectiveness of the project:

• The roadway should be paved using 18 cm of concrete and a 12 cm base layer.
• Drainage should be achieved using the curbed roadway and storm sewer pipe ranging from 75 cm to 120 cm connecting to 4thRing Canal.
• Retaining walls should be installed between Street C and Street H to prevent collapsing of the high banks.