Río Blanco Reservoir, Puerto Rico

Client: Autoridad para el Financiamiento de la Infraestructura de Puerto Rico, AFI

Contract Period: 2000-2009

Río Blanco drains the rain forest in the Luquillo mountains of Puerto Rico. However, no feasible reservoir site had been identified on Río Blanco for reservoir construction. An offstream reservoir was designed which eliminated over 90% of the sediment load, virtually eliminating the need for a large sediment storage pool. This enabled us to develop a reservoir with large hydrologic benefit, and a small sediment storage pool, and made feasible the utilization of a site which had never previously been considered for reservoir construction.

The intake structure hydraulics was designed to provide self-cleaning during flood events, and to automatically maintain minimum instream flows in the river below the intake structure. Both the innovative reservoir design and the proposed intake configuration minimized the environmental issues normally associated with reservoirs, and thereby facilitated environmental permitting.


For the Río Blanco project the firm provided the following services:

Planning. We identified the site and performed all phases of project planning and the feasibility analysis.

Engineering Studies. The firm performed hydrologic and hydraulic engineering studies related to reservoir firm yield, impact on flood levels, spillway sizing and design parameter, intake hydraulic design, and impact on environmental instream flows.

Environmental Permitting. Firm was responsible for all environmental permitting activities, including preparation of the Environmental Impact Statement.

Lead Design Firm. We are the lead design firm for this project. Civil design was performed in-house, and geotechnical and specialized structural designs were sub-contracted and performed under our direction.

Services During Construction. The firm provided inspection services for construction of the dam and appurtenant structures.