Collaborative Efforts Lead to Design and Permitting Success: Hausman Road LC-9

Andy A. Atlas, AICP, CP&Y Wesley R. Young, PE, CFM, CP&Y ASFPM May 2012

• • • • Issues Solutions Process New Tools

Overview

ASFPM May 2012

Issues for Hausman Road Project LC9

• Three low water crossings over two creeks: – Flooding on Hausman Road – Flooding of homes downstream of Hausman Road ASFPM May 2012

More Issues for Hausman Road Project

• • Roadway does not meet current design standards Local, State, and Federal Permitting required ASFPM May 2012

Initial Objectives

• • • • Improved Hausman Road with all weather access Expand roadway to current design standards Avoid/Minimize environmental impacts Remove adjacent and downstream homes from the floodplain ASFPM May 2012

Issues Complicating Objectives

• • Engineering Design – Bridge Height vs Channel Excavation Environmental Issues – Section 404 Permitting • IP vs NWP – Tree Preservation – Edwards Aquifer Recharge Zone ASFPM May 2012

Solutions

• • • Purchase property and convert to parkland Engineering – Elevate road above Huesta Creek and its tributary – Enhance channels to improve floodwater capacity – Incorporate Natural Channel Design (NCD) elements Environmental – Stream enhancement and mitigation – Tree preservation ASFPM May 2012

Means / Procedure

• • • • • NWP 27 – Aquatic Habitat Restoration, Establishment, and Enhancement Activities Stream Assessment provided baseline stream health index Add elements to channel design to enhance aquatic restoration Recalculate stream assessments for proposed conditions Monitoring required as part of NWP ASFPM May 2012

Preliminary Engineering Report

J UNE 2009

Tree Preservation Plan

J UNE 2010 F

Qualitative Habitat Evaluation Index

EBRUARY 2010

Process

Enhancement Goals

A PRIL 2010

Alternatives Analysis

M AY 2010

Mitigation Plan

J UNE 2010

Nationwide Permit 27 Pre-Construction Notification

O CTOBER 2010 ASFPM May 2012

Preliminary Engineering Report (PER)

• • • Outlined existing conditions Summarized environmental constraints including Waters of the U.S., potential wetlands, vegetation, and T&E species habitat assessment Described 3 proposed conditions options ASFPM May 2012

Qualitative Habitat Evaluation Index (QHEI)

• • • • Biologist / Engineer team assessed 15 transects across the project site Evaluated various channel / floodplain parameters Calculated scores for each transect QHEI developed by Ohio EPA ASFPM May 2012

QHEI

• • • • • • Parameters to Evaluate Substrate Instream Cover Channel Morphology Bank Erosion Pool / Glide / Riffle / Runs Gradient ASFPM May 2012

Enhancement Goals

• • • Provide unflooded access along Hausman Road Address public safety and flooding issues Enhance aquatic resources, consistent with NWP 27 • • • Return natural stream function to previously channelized stream Preserve and enhance existing vegetation Ensure that the project is financially feasible ASFPM May 2012

Enhancement Goals

USACE Objective

Preserve heritage trees Plant native trees (including understory) and grasses Reestablish vegetation Mulch and water preserved trees during construction Preserve/enhance desirable environmental features Shade pools/channel with tree canopy Reduce erosion Enhance water quality Remove exotic plant species Establish depressions for valley storage Establish riffles and pools Preserve and enhance canopy cover Plant woody buffers along streets Provide meandering low flow channel and increase channel sinuosity

CoSA

X X X X X X X X X X X X X X X X X X X X

QHEI

X X X X X X Construct small nesting islands and/or islands around heritage trees X Remove existing impervious cover Re-create floodplain function with conveyance above the low flow channel X Augment the bedrock areas with additional size substrates Add instream cover Decrease the overall stream gradient throughout the project review area X X X X Provide unflooded access along Hausman Road within the project limits Maintain or increase area of riparian woodland Provide flood protection for adjacent properties Improve wildlife habitat Manage stormwater runoff Maximize project benefits while minimizing cost X X X X

CP&Y / Program

X X X X X X X X X X X X X X ASFPM May 2012

Enhancement Goals

• • • Used the data from the QHEI Identify achievable enhancement goals Restore natural stream characteristics ASFPM May 2012

Alternatives Analysis

• • • Evaluated 5 alternatives Identified impacts of each alternative Analyzed enhancement benefits of each alternative ASFPM May 2012

Alternatives Analysis

Alternative 1: No Build Alternative 2 1 : Channel Excavation to Babcock Road Alternative 3 1 : Channel Excavation to Danvers Drive Alternative 4: Two Bridge Option Alternative 5: Three Bridge Option

Review Area Excavation

Project Total Review Area (acres) n (acres) Project Review Area to be Excavate d (%) Hausman Road Alternatives Matrix

TREES STREAMS FLOODPLAINS 5 COST

Existing Tree Canopy (acres) Tree Canopy to be Removed (acres) Tree Canopy (%) Existing Heritage Remaining (#) Heritage Trees Removed 3 (#) Heritage Trees Preserve d (%) Existing Riparian Woodland s (acres) Riparian Woodland s to be Removed (acres) Riparian Woodland s to be Preserved (%) Length of Existing Streams (feet) Linear Feet of Streams to be Excavated (feet) Streams to be Excavated (%) Length of Proposed Streams (feet) 4 Maximum 2-year Stream Velocity 4 Stream Gradient 4 (ft/mi) (ft/s) Area of 100-yr Ultimate Conditions Floodplain Remaining Outside Project Review Area (acres) Parcels with some 100 yr Ultimate Conditions (#) Residential Structures in 100-yr Ultimate Floodplain (#) 6 Overtops Hausman Road within Project Limits?

Opinion of Probable Cost (millions) 44.4

44.4

44.4

44.4

44.4

0.0

0 12.0

27% 7.8

18% 21.4

48% 21.6

49% 17.2

17.2

17.2

17.2

17.2

0.0

6.8

4.7

7.4

7.7

100% 61% 73% 57% 55% 39 39 39 39 39 0 25 9 15 11 100% 36% 77% 62% 72% 9.0

9.0

9.0

9.0

9.0

0.0

6.0

3.9

4.2

4.1

100% 3,813 33% 57% 53% 54% 0 3,813 3,490 3,813 2,880 3,813 1,900 3,813 2,620 0% 1,800 92% 1,800 76% 1,800 50% 2,100 69% 2,100 11.5

8.2

8.2

5.2

5.2

42 33 33 28 28 7.1

2.7

6.0

2.7

2.7

55 26 44 27 28 30 9 22 9 9 Yes No No No No _ $7.1

$6.1

$8.8

$8.8

Notes 1: The level of impact analysis for Alternatives 2 and 3 is not as detailed as the analysis for Alternatives 4 and 5 because Alternatives 4 and 5 are refinements of Alternative 2 and have been carried to a higher level of design.

2: At the time of the heritage tree survey, right of entry was not available in the southwestern corner of the project review area. Therefore, some heritage trees may not have been counted in this total.

3: Infringement of the root protection zone was considered removal.

4: Based on the preliminary hydraulic design.

5: The quantities in this section refer to the Huesta Creek floodplain and include areas adjacent to the project review area, south of Hausman Road and west of Babcock Road.

6: The Alternatives matrix was conducted using 2009 Bexar County aerial photography, and as a result, newly constructed houses that have been built after the date the aerial photos were flown have not been quantified.

ASFPM May 2012

•

Recommended Alternative 5

3 Bridge Option with Channel Enhancements – Removes 21 residences from floodplain – – – – Provides unflooded access Provides extensive aquatic enhancements Preserves over 70% of heritage trees Preserves over 50% of riparian woodlands ASFPM May 2012

• • •

Tree Preservation Plan

Coordinated with City Arborist Selection of plants had to meet enhancement goals of USACE Plan coordinated for channel design – Planting density vs hydraulic roughness – Planting locations ASFPM May 2012

Mitigation Plan

• • • • Must address deficits identified in QHEI Based on the enhancement goals Must be verifiable and quantifiable Must conform to USACE expectations for aquatic enhancement ASFPM May 2012

Table 1: Objectives, Metrics, and Proposed Actions/Results

Objective

Preserve heritage trees

Metric and Enhancement Goal Met

Calculate percentage of heritage trees preserved under preferred alternative.

Enhancement goal met by objective: 5 Proposed Action/Results

A total of 72 heritage trees were identified in the project area. Project engineers incorporated minimization and avoidance measures where possible into the project design. Construction of the project would require the removal of 15 heritage trees; however, as detailed in the Tree Preservation and Planting Plan, these impacts would be mitigated with a total of 482 trees and shrubs native to the San Antonio area. Plant native trees and grasses Reestablish vegetation Mulch preserved trees during construction Calculate number of trees by species, canopy cover, and area of native trees and grasses to be planted. Monitor species survival rate for a period that will be finalized by CoSA and the USACE.

Enhancement goal met by objective: 3, 5

A total of 482 native trees and shrubs would be planted in the project area. Additionally, 21.2 acres of native grass seed would be planted. The survival rates of these plantings would be monitored for a period agreed upon by the USACE and CoSA. Please refer to the Tree Preservation and Planting Plan in Attachment B for more details on species compositions and proposed planting locations. Calculate area of impervious cover converted to vegetation. Monitor species survival rate for a period that will be finalized by CoSA and the USACE.

Enhancement goal met by objective: 5

Approximately 3.9 acres of existing roadways and concrete slabs would be removed from the project area. Native grass seed would be planted in these areas (please refer to Attachment B for proposed planting plan). The survival rates of these plantings would be monitored for a period agreed upon by the USACE and CoSA.

Identify areas of preserved trees requiring mulching. Monitor species survival rate for a period that will be finalized by CoSA and the USACE.

Enhancement goal met by objective: 5

An orange mesh barrier fence would be placed around the root protection zone (RPZ) of trees to be preserved. The areas inside the fencing would be mulched to reduce moisture stress. The survival rates of these plantings would be monitored for a period agreed upon by the USACE and CoSA.

Preserve/ enhance desirable environmental features Identify rare/native vegetation and habitats. Calculate areas by habitat type. Calculate percentage of these areas preserved by preferred alternative.

Enhancement goal met by objective: 3, 4, 5

An area containing a mix of native grasses and herbaceous species was identified south of Hausman Road, between Huesta Creek Channel Two and Huesta Creek Tributary A. Roughly 90 percent of this area would be preserved with approximately 17 native tree plantings along the eastern edge. ASFPM May 2012

Table 2: Summary of Existing Conditions vs. Proposed Improvements

Objective

Preserve heritage trees and preserve/enhance desirable environmental features Remove exotic plant species and plant native trees and grasses Preserve and enhance canopy cover Improve wildlife habitat Establish depressions Establish riffles and pools Provide meandering low flow channel and increase channel sinuosity

Existing Conditions

72 heritage trees in project review area Numerous exotic and/or invasive species

Proposed Actions

57 heritage trees to be preserved; 164 potential heritage trees (canopy value of 875 ft 2 or more) to be planted; 21.2 acres of native grass and wildflowers to be planted. Would preserve existing area containing a mix of native grasses and herbaceous species.

67 mature (DBH ≥ 6 inches) invasive/exotic trees removed; 482 native trees planted 16.3 acres of canopy cover in project area 12.2 acres would be preserved; 5.3 acres to be added Channelized creek, impervious cover, and numerous invasive species compromise value of wildlife habitat No depressions are present No riffles or pools present Plant 482 native trees and 21.2 acres of native grasses and wildflowers that provide food and shelter to wildlife 20 aquatic depressions totaling 21,600 sq ft (0.5 acres) proposed 22 check dams/riffles to be placed within the three proposed watercourses Existing sinuosity rating: none to moderate Proposed sinuosity rating: moderate to high ASFPM May 2012

NWP 27 PCN

• • • • Adapted NWP 14 application form to NWP 27 as per USACE recommendation Form simplifies the process Incorporated Mitigation Plan and previous documents as appendices NWP 27 approved without comment ASFPM May 2012

Keys to Success

• • • Clearly defined goals Collaborative approach between and within agencies, program, and consultant team Communication (monthly progress meetings with program and team progress meetings) ASFPM May 2012

Results / Benefits

• • • • • • • By coordinating the engineering design with permitting requirements: Sustainable design Buy-in from all stakeholders NWP 27 approved without comment Significant time savings Cost Savings Remove downstream homes from the floodplain Stream restoration/enhancement ASFPM May 2012

Current Assessment Tools - TXRAM

• • • QHEI replaced by TXRAM Texas Rapid Assessment Method Aquatic Resource Compensation Calculator ASFPM May 2012

Thank You’s

• • • • • Bexar County Flood Control Program City of San Antonio Storm Water Engineering USACE Fort Worth District AECOM Terra Design Group ASFPM May 2012

Questions?

ASFPM May 2012