Parra & Co

Boutique-level site civil, drainage, and infrastructure engineering for Texas growing communities

About the firm

Parra & Co is a San Antonio-based engineering practice delivering site civil, stormwater, wastewater, transit, land development, and master planning services to public and private clients across Texas. It emphasizes a personalized, boutique-level experience, backed by senior project managers with over two decades of individual industry experience.

Firm type: Civil Engineering · Water / Wastewater Engineering · Transportation Engineering

Credentials

TBPE Firm Registration No. F17744

Capabilities

Stormwater and Drainage Engineering

Custom drainage solutions designed to mitigate flood risks, manage storm runoff, and enhance urban resilience through sustainable water infrastructure.

Stormwater Management Plans
Comprehensive plans and reports illustrating existing and ultimate runoff conditions to evaluate municipal storm sewer system impacts.
Hydrological and Hydraulic Analysis
Advanced modeling utilizing specialized software and rainfall data to assess drainage infrastructure capacity and mitigate localized ponding.
Green Infrastructure Design
Eco-friendly stormwater systems incorporating bioswales, permeable pavements, and rain gardens to promote natural groundwater recharge.
Detention Pond and Infiltration Basin Design
Engineered retention and detention facilities that optimize water conveyance and control peak discharge rates.

Platting and Land Development

End-to-end guidance from initial land due diligence to final recorded plats, ensuring strict compliance with local unified development codes.

Minor and Major Plat Processing
Efficient processing of simple minor lot adjustments and complex major subdivisions through municipal planning departments.
Plat Exceptions and Certificates of Determination
Investigating parcel history and sizing to apply for formal platting exemptions under municipal ordinances.
Site Assessment and Due Diligence
Thorough reviews of zoning, environmental constraints, utility accessibility, and existing infrastructure to evaluate site viability.
Master Planning
Strategic, long-range master plans focusing on optimized land use, transportation, utility layouts, and sustainable community growth.

Transit and Transportation Engineering

Site civil design for multimodal facilities and corridor improvements that support regional connectivity and commuter transit networks.

Transit Facility Civil Engineering
Comprehensive design for bus maintenance bases, operations centers, and mobility hubs with integrated vehicle staging.
Street Rehabilitation Design
Paving, roadway grading, and infrastructure repairs designed to improve vehicular access and extend corridor lifespans.
Traffic Impact Analysis
Meticulous vehicle volume and pedestrian safety surveys to assess access points and evaluate local road network impacts.
Grant Application Assistance
Technical planning, phasing, and cost estimation support for regional transit grants, including Federal Transit Administration (FTA) and federal discretionary applications.

Water and Wastewater Engineering

Potable water distribution and municipal wastewater management engineering that prioritizes treatment efficiency and system redundancy.

Water Distribution System Design
Hydraulic planning and design of water mains, distribution networks, and localized line extensions.
Wastewater Treatment Plant Design
Design of municipal and commercial wastewater treatment facilities, including activated sludge and sequence reactor systems.
Irrigation and Drip Field Design
Design and performance specification of custom drip field disposal and land application irrigation networks.
TPDES Permitting
Preparation, regulatory response, and quality assurance reviews for Texas Pollutant Discharge Elimination System permits.
Operations and Maintenance Manuals
Highly structured, searchable manuals detailing startup, routine, and emergency operations for treatment facilities and mechanical sub-units.

Vertical Facilities Design

Integrated structural support, space planning, and project coordination for commercial and residential buildings.

Commercial and Residential Building Design
Functional and sustainable architectural and civil design coordination focused on site optimization and structural performance.

Project Management

Comprehensive project oversight ensuring execution is aligned with schedule milestones, budgets, and quality standards.

Construction Administration and Inspection
Real-time construction oversight, site inspections, submittal reviews, and warranty assistance to guarantee design compliance.
Permitting Assistance
Proactive agency coordination and submission management to secure prompt regulatory and municipal development approvals.

Industries

Transit · Education · Water Supply · Wastewater · Stormwater & Flood Control · Land Development · Government · Commercial · Residential · Utilities

Projects

Palo Alto College Drainage System Improvement

San Antonio, TX · Education · Client: Alamo Colleges (sub-consultant to WestEast Design Group)

Project details

A multi-phase drainage mitigation and site civil design project at Palo Alto College to address foundation movement caused by expansive soils. Phase 1 involved a comprehensive evaluation of construction documents and campus conditions to produce priority-based recommendations. Phase 2 delivers a Stormwater Management Plan (SWMP) with hydrological and hydraulic analyses, regrading around affected buildings, connecting downspouts to the storm sewer system, and designing a gravity-fed storm sewer network.

Northeast Lakeview College Drainage System Improvement

San Antonio, TX · Education · 2024 · Client: Alamo Colleges (sub-consultant to WestEast Design Group)

Project details

A campus-wide drainage and foundation settlement mitigation project covering a 166-acre campus. The scope of work includes executing a Stormwater Management Plan (SWMP) with hydrological analysis to manage runoff from upstream parking lots, performing site regrading and downspout connections, and developing targeted improvements for Salado Hall (Academic 1 Building) such as trench drain upgrades to protect building foundations. The practice also provides permitting assistance and construction administration to ensure quality and compliance.

St. Philip's College Drainage System Improvement

San Antonio, TX · Education · Client: Alamo Colleges (sub-consultant to WestEast Design Group)

Project details

A drainage mitigation and stormwater modeling project for a 60-acre campus experiencing foundation settlement. The project includes hydrological and hydraulic modeling of the campus's stormwater systems utilizing InfoDrainage software, Atlas 14 rainfall data, and Unified Development Code guidelines to identify flood-prone areas and inform targeted mitigation designs.

R.E.A.L. Multimodal Transit Facility

Alice, TX · Transit · Client: Rural Economic Assistance League (sub-consultant to Able City)

Project details

Civil engineering and stormwater design for a new multimodal transit facility featuring a 16,964 sq ft administration building, an 11,589 sq ft maintenance building, and extensive parking. The scope includes preparing site civil construction documents, a stormwater management plan, a hydrology report with detention basin design, a LEED feasibility report, and a water line extension. The design incorporates temporary and permanent strategies to accommodate the future county stormwater network.