Northpark Drive Mobility Project

EHRA completed preliminary engineering, phase one environmental site assessment and schematic development for the widening of Northpark Dr. between US 59 and Woodland Hills Dr. EHRA also provided program management, drainage analysis and design, traffic engineering, environmental documentation and schematic design for the roadway, as well as grade separation at the Loop 494/UPRR railroad crossing.

EHRA conducted traffic operations and access management studies for the Northpark Dr. corridor. This corridor is approximately 2.2 miles long and has major signalized and unsignalized intersections and driveways that access various subdivisions and industrial developments. These studies laid the groundwork for the widening of Northpark Dr. from a four-lane boulevard cross-section to a six-lane boulevard complete street. The new street design includes low impact development drainage, conventional drainage, a grade separation at the UPRR crossing with mechanically stabilized earth retaining walls, two at-grade crossings for bi-directional frontage access, reconstruction of two concrete bridges over a diversion channel, intersection improvements, a roadway-adjacent multiuse path and traffic signal improvements.

Drainage analysis and design included hydrologic and hydraulic studies of both existing and proposed conditions to demonstrate that proposed project components would not adversely affect the 100-year floodplain in the area. The roadway and traffic designs contained horizontal and vertical alignments, cross-sections, plan and profile, sidewalk and bicycle accommodations, intersection layouts, traffic control plans and signing and pavement markings.

As the program management firm, EHRA coordinated with TxDOT, UPRR, the City of Houston Council District E, COH Planning and Development Department, COH Public Works and Engineering Department, Montgomery County, Harris County, HCFCD and area residents throughout the project.

Towne Lake

In 2006, Caldwell Companies sought to create Towne Lake as a community where residents and services could be connected by water. Their vision included boat docks and marinas augmenting traditional walking trails to navigate a vibrant residential community. EHRA was the perfect partner to take Caldwell Companies’ vision and create this livable suburban oasis.

Cane Island Parkway

The new roadway design comprises of one-half major thoroughfare, conventional drainage, a 600-ft long bridge over Willow Fork Bayou, Retaining walls and intersection improvements at FM 1463 (including traffic signals and illumination).

Jacobs Reserve Development

Engineering design and construction phase services of water, sewer, drainage and paving for four subdivision sections and off-site channel (123 acres out of a 400 acre subdivision). There was 60-feet of elevation difference on this site and wooded lots were left in their natural state which required the installation of retaining walls.

Greens Bayou Trail Phase 3

Identified as a top priority during the development of the District’s Parks Master Plan, this portion of trail was the first phase of over two miles of planned trails to provide connectivity and recreation for District residents.

29 June 2022

Project InFocus: Foxwood Subdivision Improvements

Andy Palermo P.E. CFM Senior Vice President

Foxwood Subdivision Improvements

Harris County enlisted EHRA to perform a planning-level engineering investigation for the Foxwood Subdivision, located in northern Harris County. The objectives of the investigation were to determine the causes of flood losses reported within the residential community, to reduce the risk of structural flooding and improve resiliency in the subdivision.

Project Manager Jennifer Hundl, PE, CFM, LEED AP applied the Rational Method when analyzing the existing storm sewer system for the two-year rainfall design. In addition, our engineers analyzed extreme event flow paths using the Hydrologic Engineering Center’s River Analysis System two-dimensional (HEC-RAS 2D) software. This system’s rain-on-grid exercise utilized available light detection and ranging (LiDAR) information and rainfall for the existing one percent 24-hour event. Our investigation also involved taking an inventory of existing utilities and ingress/egress routes to the neighborhood.

After critical data was compiled, EHRA recommended changes intended to increase inlet capacity in the areas of repetitive flood loss. The results of the HEC-RAS 2D analysis revealed that Foxwood did not have adequate extreme event overflow infrastructure. To resolve this deficit, we recommended the acquisition of a particular property that would allow construction of the necessary extreme event overflow structure and reduce the risk of structural flooding.

EHRA participated in a community engagement meeting to discuss investigation results and subsequent recommendations. Our team fielded comments and addressed community member questions. EHRA further initiated and engaged in discussions amongst local MUD and Harris County Precinct 4 staff members to encourage a construction partnership between the entities.

EHRA performed another subsequent drainage analysis in the area. This analysis was a non-detailed, two-dimensional study evaluating how rainfall interacts with the local topography. The purpose of this additional study was to identify overflow limits versus surveyed finished floor elevations. Previous recommendations were then appraised using updated Atlas 14 rainfall totals. The project was completed in 2021.

HYDROLOGY & HYDRAULICS Project In Focus