Water Quality Analysis Report for Residential Development Project at 353 Main Street, Redwood City, California

June 28, 2017

Sam Knutson ROEM Development Corporation 1650 Lafayette Street, Santa Clara, CA 95050

Subject: Water Quality Analysis Report for Residential Development Project at 353 Main Street, Redwood City, California

Dear Mr. Knutson:

Tetra Tech, Inc. is pleased to provide ROEM Development Corporation with this Water Quality Analysis Report, revised based on City of Redwood City staff comments. Please let me know if you have any questions or would like to discuss how these comments are addressed.

Sincerely,

John R. Bock Senior Environmental Scientist

Enclosure

Tetra Tech, Inc. 1999 Harrison Street, Suite 500, Oakland, CA 94612 Tel 510.302.6300 Fax 510.433.0830 www.tetratech.com

WATER QUALITY ANALYSIS Tetra Tech did a hydrology and water quality analysis to support the California Environmental Quality Act (CEQA) requirements for the proposed residential development project at 353 Main Street in Redwood City, San Mateo County, California.

Purpose and Scope

Purpose. This analysis evaluates these ten CEQA environmental checklist questions, as they relate to the project site that is slated for residential development, to determine if the proposed project would:

 Violate any water quality standards or waste discharge requirements?  Substantially deplete groundwater supplies or interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or a lowering of the local groundwater table level (e.g., the production rate of pre-existing nearby wells would drop to a level which would not support existing land uses or planned uses for which permits have been granted)?  Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, in a manner which would result in substantial erosion or siltation on- or off-site?  Substantially alter the existing drainage pattern of the site or area, including through the alternation of the course of a stream or river, or substantially increase the rate or amount of surface runoff in a manner which would result in flooding on- or off-site?  Create or contribute runoff water which would exceed the capacity of existing or planned storm water drainage systems or provide substantial additional sources of polluted runoff?  Otherwise substantially degrade water quality?  Place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map?  Place within a 100-year flood hazard area structures which would impede or redirect flood flows?  Expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam, or dam inundation?  Cause inundation by seiche, tsunami, or mudflow?

Scope of Analysis. This included a thorough review of all available background materials and reports to evaluate the applicable items on the CEQA checklist and to determine data adequacy, accuracy, and potential environmental impacts. This review included site-specific reports, such as the project design plans, Geotechnical Engineering Study (ESP 2016), Phase I Environmental Site Assessment (AEI Consultants 2016), Environmental Data Report (EDR) NEPACheck (EDR 2017), City of Redwood City North Main Street Precise Plan (City of Redwood City 2008; hereafter referred to as the Precise Plan), 2015 Urban Water Management Plan, City of Redwood City (EKI 2016), recent studies on hydrogeology, groundwater/surface water supply and interactions, city water quality reports, and readily available electronic data, databases, and GIS coverages. Complete references are at the end of this report.

The following data gaps were identified:

1) Flood zone identification – current available flood zone information as acquired through a study of readily available maps and databases, rather than actual land survey data. It is understood that the flood zone maps are currently under review and may change. This 2

CEQA analysis was based on the current, known flood zones and the understanding that the subject property will be constructed outside the currently defined 100-year flood zone, in accordance with the building and zoning codes specified in the Precise Plan and other applicable policies and requirements. 2) Groundwater levels, flow directions, gradients, and interconnectivity with surface water – groundwater data that were reviewed and analyzed came from existing available reports and on-site, boring log data in the Geotechnical Engineering Study (ESP 2016). 3) Unknown/undocumented artificial fill materials underlying the project site – directly beneath the project site are artificial fill materials that have been described as “poorly consolidated to well-consolidated gravel, sand, silt, and rock fragments in various combinations used in a variety of applications including highway, railroad, and road fill, earth-fill dams and embankments, and building-site grades” (Pampeyan 1993; ESP 2016). These artificial fill materials extend to an approximate depth of 6.5 feet. Although not believed to be a significant environmental threat or risk, the fill could contain elevated levels of metals, solvents, and petroleum product constituents.

Scope of Project. The scope of the project is to demolish the existing one-story medical building at the northwest portion of the site and replace it with a four- to five-story apartment building over a two-level, podium parking garage. The lowest level of the parking garage will be depressed on the order of 5 feet below the existing grade and above the local shallow groundwater table (presumed to be about 15 feet below ground surface [bgs]). Based on the site plan, this multi- residential structure will be centered on the project site and will be zoned as a planned community, with 125 dwelling units. The apartment facility will be separated from Redwood Creek by an adjacent bike path that will provide a buffer from potential flooding, as specified in the Precise Plan.

Introduction and Background Information

Site Description. Redwood City is at the geographic center of the San Francisco Peninsula, about 25 miles from both San Francisco and San Jose, California. The subject property is in the northeastern portion of Redwood City, in San Mateo County, west of the San Francisco Bay and east of Highway 101 (Figure 1). The property at 353 Main Street is included in the Precise Plan that serves as a regulatory document amends the City of Redwood City Zoning Code and implements the City of Redwood City General Plan to implement the City’s revitalization objectives for the greater downtown and Bayfront areas with policies to expand the city’s housing supply (City of Redwood City 2008). Defined for the purposes of this report as the area within which all ground-disturbing activities associated with the project would occur, the project site is an irregularly shaped 1.617-acre feature; the site is part of the larger project parcel. A single-story medical building is in the northwest portion of the site. Redwood Creek wraps around the northeastern edge of the site and bounds the property to the east (Figure 2). The remainder of the project site is covered by an asphalt parking lot and irrigated landscape islands (ESP 2016). Main Street bounds the project site to the southwest, with a multi-story residential development to the northwest, and a medical building and restaurant to the south of the property.

Climate. Redwood City is in a region characterized by a Mediterranean climate with cool, wet winters, and warm, dry summers. Average temperatures range from 48 to 70.5 degrees Fahrenheit (oF). Rainfall averages 18.6 inches per year and generally occurs during late October to early May. The average annual reference evapotranspiration is 45 inches per year; approximately 26 inches more than the average annual precipitation, so there is a significant amount of irrigation during the dry season.

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Figure 2

Surface Water. Redwood Creek wraps around the northern and eastern boundaries of the project site. As noted in the project design plans, the majority of the project site is in Flood Zone X, indicating that the site is determined to be outside of the area with a 0.2 percent annual chance of a flood. The perimeter of the site that is adjacent to Redwood Creek is delineated in Flood Zone AE, defined as areas of the 1 percent annual flood (100-year flood zone). Also known as the base flood, the flood has a 1 percent chance of being equaled or exceeded in any given year (Flood Insurance Rate Map Community No. 060325 0301 E, dated October 16, 2012). Based on City of Redwood City staff comments received on May 25, this Federal Emergency Management Agency (FEMA) flood map is expected to change before the project is completed, and the majority of the site is anticipated to have a base flood elevation of 10 feet. The project will be designed to meet FEMA requirements, including no basements below base flood elevation and waterproofing.

The Redwood Creek system is the largest watershed in the area covered by the Redwood City General Plan (City of Redwood City 2010). From around U.S. Highway 101 to the north, Redwood Creek flows in a channel to the San Francisco Bay. The northern reaches of Redwood Creek separate Bair Island from the Port of Redwood City. Between Bair Island and the Port of Redwood City, Redwood Creek flows into an intertidal zone with fresh water from the creek and San Francisco Bay salt water mixing in an area that widens to a small-craft navigable bay channel. Saltwater and freshwater marshes form a buffer between Redwood Creek and the San Francisco Bay.

Based on an Initial Study done at the neighboring 333 North Main Street property, Redwood Creek overflowed its banks during a 100-year flood in 2004 (Metropolitan Planning Group 2011). Redwood Creek is tidally influenced in its reach from the Precise Plan area downstream to San Francisco Bay; the water level in the creek reportedly can fluctuate 4 to 6 feet from tidal influences.

Hydrogeological Environment. Four geotechnical test soil borings were drilled on the project site to depths of 20 to 50 feet bgs on August 30, 2016 (ESP 2016). The test borings showed approximately 6.5 feet of fill material beneath the project site. Based on these test borings and other available geologic maps and literature, the project site is underlain by artificial fill described as “a mixture pf lean and fat clays, and variable amounts of sand and gravel, with soil moistures ranging from 13 to 14 percent. The artificial fill is underlain by Bay Mud described as ‘bluish gray’, soft Bay Mud encountered to depths ranging from 13.5 to 15 feet bgs. Lean to fat clays with variable sand content and consistencies were encountered in the soil borings at depths of approximately 18 to 24 feet. Below this layer granular soils were encountered, consisting of medium dense to dense poorly graded sand with variable silt and gravel” (ESP 2016). In the deepest soil boring, the granular layer was encountered to approximately 35 feet followed by stiff lean to fat clays to the bottom of the boring at 50 feet” (ESP 2016).

Groundwater was generally encountered between 18 to 18.5 feet bgs during drilling and recovered to about 13 feet bgs immediately following the drilling. Based on the test boring results, ESP surmised that the groundwater elevation is about the same as the elevation of the surface of the adjacent Redwood Creek. Site-specific details regarding the groundwater flow direction, gradient, and seasonal variability are unavailable. However, according to the City of Redwood City 2015 Urban Water Management Plan (EKI 2016), “depending upon streamflow, recharge, and pumping conditions, groundwater flow likely occurs in interchangeable directions” and is most likely influenced by whether Redwood Creek is acting as a gaining stream or losing stream, and by tidal fluctuations.

On a regional scale, Redwood City overlies the southern end of the San Mateo Plain Subbasin of the Santa Clara Valley Groundwater Basin (Groundwater Basin 2-9.03), as characterized by the 6

California Department of Water Resources (DWR 2004). This subbasin is not adjudicated and is ranked as a “very low priority” basin under the California Statewide Groundwater Elevation Monitoring (CASEGEM) basin prioritization process, implemented under the Sustainable Groundwater Management Act (SGMA). The San Mateo Plain Subbasin contains shallow and deep aquifer systems separated by low-permeability clays. The main sources of natural recharge to the local groundwater system is from surface water infiltrating along streambeds in the surrounding upland areas in the drainage basin, and to a lesser extent by percolation of precipitation and infiltration of applied irrigation water. Subbasin outflows include limited municipal and private well pumping and groundwater outflows across subbasin boundaries. Groundwater overdraft has been avoided because groundwater is not currently used as a source of municipal water supply in Redwood City.

Hydrology and Water Quality Analysis

The following 10 CEQA environmental checklist questions, as they pertain to potential impacts and environmental consequences regarding the proposed site development project for 353 Main Street, were analyzed and are discussed.

Would the project violate any water quality standards or waste discharge requirements? (Less than Significant with Mitigation)

Existing sources of pollutants discharging into surface waters at the project site could include stormwater runoff, petroleum and other solvents from parking lots, pesticides from landscaping, or sediment from soil erosion. Chapter 27A (Stormwater Management and Discharge Control Program) of the City Code of Redwood City contains the City of Redwood City’s policies intended to govern the quantity and quality of stormwater discharge produced in the city limits. As an implementation tool, the City of Redwood City designed an “NPDES Permit Requirement Checklist” to help with implementation of its own SMCWPPP (this checklist can be accessed online at: http://www.redwoodcity.org/home/showdocument?id=2018). Site design measures applicable to the 353 Main Street development project that are specified in the checklist include:  Protect sensitive areas and minimize changes to the natural topography – the new multi- residential development will be centered on the redeveloped project site with minimal new land disturbance  Minimize impervious surface areas – as shown on Figure 2, the project site is already developed and is primarily covered with impervious asphalt pavement  Minimize impervious areas from being directly connected to the storm drain system (e.g., direct roof downspouts to vegetated areas where feasible)  Maximize permeability by preserving open space – the Precise Plan requires that new development reconfigure top-of-bank areas to incorporate a creekside trail and wetland overlook areas  Use permeable pavement surfaces where feasible – the implementation of the Precise Plan is anticipated to reduce the amount of impervious surface, replacing some of the current asphalt pavement with a buffer zone between the property boundary and Redwood Creek  Use landscaping to treat stormwater – the current and proposed design plans include this in the site design  Use “Bay Friendly Landscape Guidelines – Sustainable Practices for the Landscape Professional” As a result of the mitigation measures in-place in the Precise Plan and NPDES Permit Requirement Checklist, the project would have a less than significant impact on water quality standards and waste discharge requirements.

Would the project substantially deplete groundwater supplies or interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or a lowering of the local groundwater table level (e.g., the production rate of pre-existing nearby wells would drop to a level which would not support existing land uses or planned uses for which permits have been granted)? (No impact)

Currently, all of Redwood City’s drinking water is supplied by the Hetch Hetchy regional water system operated by the San Francisco Public Utilities Commission (SFPUC) (City of Redwood City 2017). According to the 2015 Urban Water Management Plan for the City of Redwood City (EKI 2016), “To date, the City has not utilized groundwater as a potable water source…the sole source of City’s potable water has been wholesale water supplied by the SFPUC Regional Water System (RWS) and does not expect to utilize groundwater as a regular potable water source in the future.” The San Mateo Plain Subbasin is currently designated by DWR as a “very low priority” basin and is exempt from complying with SGMA.

According to the Redwood City New General Plan Environmental Impact Report (City of Redwood City 2010): “Groundwater is not used as a source of municipal water supply. Future new development allowed under the New General Plan would obtain municipal water from the Hetch Hetchy regional water system operated by the SFPUC and recycled water for non-potable uses. Thus, potential development allowed by the New General Plan should not result in a depletion of groundwater supplies, as such a type of water source is not utilized within the plan area.”

Because the City of Redwood City’s water supply is provided by the SFPUC RWS, there are no consequential groundwater withdrawals associated with the 353 Main Street multi-residential development project. So, there is no impact or depletion to groundwater supplies or substantial changes in groundwater recharge that would cause a net deficit in aquifer volume or lowering of the local groundwater level.

Would the project substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, in a manner which would result in substantial erosion or siltation on- or off-site? (Less than Significant)

According to the Redwood City New General Plan Environmental Impact Report (City of Redwood City 2010): “The New General Plan would allow Bayfront area development close to the Redwood Creek channel and adjacent tributaries, which could increase the amount of impervious surfaces, which would alter existing drainage patterns.” At the project site, the effects of potential drainages are anticipated to be less than significant, because of the amount of surface area (asphalt parking lot) that is already paved. Construction of the trail and use of landscaping along the eastern perimeter of the site may effectively decrease the impervious surface. The New General Plan includes policies and implementation programs to protect and preserve creeks and establish development limitation programs to protect and preserve Redwood Creeks and similar drainages. For example, Policies NR-5.3 through NR-5.6 for the New General Plan would establish creek buffer zones for new development.

With adherence to and implementation of the New General Plan policies and implementation programs, impacts related to drainage patterns would have a less than significant impact regarding controlling the potential for erosion or siltation on- or off-site.

Would the project substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, or substantially increase

the rate or amount of surface runoff in a manner which would result in flooding on- or off- site? (No Impact)

As discussed in the Redwood City New General Plan Environmental Impact Report (City of Redwood City 2010), “Future infill and redevelopment within the plan area is not anticipated to substantially increase the amount of existing impervious surfaces, as development allowed by the New General Plan would occur largely within areas currently developed with urban uses, including downtown, surrounding neighborhoods and major transportation corridors.” Such is the case for the 353 Main Street development project.

Policies NR-5.1, NR-5.6, and NR-7.3 of the Redwood City New General Plan are intended to promote natural stream channel function and restore and enhance existing waterways through the reduction of urban runoff and ecologically enhancing methods. In addition, New General Plan Policy PS-7.6 requires that impervious surfaces be minimized to reduce stormwater runoff and increase flood protection.

An EDR NEPACheck of the subject property was used to generate a flood plain map (Figure 3) that shows the 100-year flood zone is beyond the project site boundary, but within the buffer zone of the Redwood Creek setback easement (EDR 2017). However, the residential development is completely confined within the property boundaries. Tetra Tech reviewed the California Office of Emergency Services (OES) MyHazards database (http://myhazards.caloes.ca.gov) and determined that the project site is in or near an area of low hazard for flooding (Figure 4). As discussed and shown on Figure 2, the project site is already developed and the majority of the site covered with impervious surfaces (existing building and asphalt pavement). Because the New General Plan requires a buffered area between the project site and Redwood Creek, the existing potential of flooding would be further minimized.

As a result, no impacts are anticipated from the project related to potential increase in the rate or amount of surface runoff in a manner that would result in flooding on- or off-site.

Would the project create or contribute runoff water which would exceed the capacity of existing or planned storm water drainage systems or provide substantial additional sources of polluted runoff? (Less than Significant with Mitigation)

Site-specific BMPs recommended in the Geotechnical Engineering Study to improve site drainage include (ESP 2016):  Finish-grade unpaved ground surfaces to direct surface runoff away from site improvements at a minimum five percent grade for a minimum distance of 10 feet, or if not practical, provide swales to divert drainage away from improvements  Install landscaping to maintain proper surface drainage conditions  Divert runoff from driveways, roof gutters, downspouts, planter drains, and other improvements to discharge in a non-erosive manner away from foundations, pavements, and other improvements  Grade the site so runoff is allowed to flow in an uncontrolled manner over cut, fill and natural slopes  Stabilize surface soils by vegetation or other means during and following construction  Seal sides and bottoms of raised planter beds adjacent to foundations so that irrigation water is not allowed to penetrate the subsurface beneath foundations  Provide drain outlets in planted areas to direct accumulated water away from foundations  Control irrigation systems to sustain vegetation without fully saturating the soil  Bioretention swales constructed within 10 feet or less from the building foundation should be lined with a 20-mil pond liner

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Project Location 353 Main Street Redwood City 100-Year Flood Zone San Mateo County, California 500-Year Flood Zone Figure 3 San Francisco Bay

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Additional construction BMPs are provided in Sections D (Erosion and Sedimentation Control and E (Construction BMPs) of the City of Redwood City Stormwater Pollution Prevention NPDES Permit Requirements Checklist (http://www.redwoodcity.org/home/showdocument?id=2018).

Assuming project implementation of these BMPs, impacts related to the capacity of storm water drainage systems and polluted runoff would be less than significant.

Would the project otherwise substantially degrade water quality? (Less than Significant)

In addition to the rules, policies, and guidelines discussed above, Redwood City is one of a series of communities in San Mateo County that have joined together to form the San Mateo Countrywide Water Pollution Prevention Program that complies with waste discharge requirements under the NPDES permit to discharge stormwater runoff from storm drains and watercourses (NPDES Permit No. CAS612008 and amended by Order NO. R2-2015-0049). Provision C.3 of the permit that addresses “New Development and Redevelopment.” is applicable to this project. The goal of Provision C.3 is for the Permittees (including Redwood City) to include the appropriate source control, site design, and stormwater treatment measures in new development and redevelopment projects to address stormwater-runoff pollution discharges and prevent increases in runoff flows for new development and redevelopment projects (City of Redwood City 2016). This goal is accomplished primarily through implementation of low impact development (LID) techniques. Performance standards include evaluation of potential water quality effects and appropriate mitigation measures.

Under the NPDES permit, redevelopment projects that alter 50 percent or more of the impervious surface of a previously existing development must include all existing, new, or replaced impervious surfaces in the treatment system design. For example, stormwater treatment systems must be designed and sized to treat stormwater runoff from the entire redevelopment project.

The Redwood City New General Plan includes policies and implementation programs that protect and preserve creeks and establish development limitation programs. No impact on groundwater quality is anticipated because controls are in-place to protect the surface water resources in Redwood Creek that could infiltrate to groundwater and there are no groundwater recharges or discharges (such as groundwater injections or withdrawals) anticipated that could alter otherwise affect or degrade water quality. The future residential community and increased population adjacent to Redwood Creek could have some minor, consequential effects on water quality (such as increased littering), but those impacts are expected to be minimal.

As a result of adherence to the New General Plan policies, implementation programs, and NPDES permit requirements, the project would have a less than significant impact on water quality.

Place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map? (No Impact)

The OES MyHazards database (http://myhazards.caloes.ca.gov) indicates that the project site is in or near an area of low hazard for flooding. The EDR NEPACheck of the subject property generated a floodplain map (Figure 3) that shows the 100-year flood zone is beyond the project site boundary but is in the buffer zone of the Redwood Creek setback easement (EDR 2017). As shown on Figure 3, the project site and future residential development are not currently in a 100- year federal flood hazard area, so there would be no impact.

Would the project place within a 100-year flood hazard area structures which would impede or redirect flood flows? (No Impact)

The project would have no impact because the residential development is completely confined within the property boundaries and the new development would not impede or redirect flood flows.

Would the project expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam, or dam inundation? (No Impact)

Because the project site is not in the 100-year flood hazard area, is in or near an area of low hazard for flooding, and is not in an area protected by a levee or dam, the project would have no impact.

Would the project cause inundation by seiche, tsunami, or mudflow? (Less than Significant)

Seiche. A seiche is a tidal change in an enclosed or semi-enclosed water body caused by sustained high winds or an earthquake. Due to the project site’s proximity to the San Francisco Bay, the project area could experience seiche or seiche-related effects during sustained seismic activity. Because the project site is in a recessed, buffered area adjacent to Redwood Creek, rather than directly along the San Francisco Bay shoreline, the severity of the seiche energy should be decreased upon reaching the project site. So, a less than significant impact regarding seiche inundation is anticipated.

Tsunami. A tsunami is a sea wave generated by an earthquake, landslide, volcanic eruption, or even by a large meteor hitting the ocean. The California OES MyHazards database (http://myhazards.caloes.ca.gov) indicates that the project site is outside of a tsunami zone (Figure 4). It should be noted that the Tsunami Inundation Map for Emergency Planning (California Emergency Management Agency 2009) indicates that the portion of Redwood Creek bordering the northwestern property boundary is in the tsunami zone, although the risk of a tsunami would be substantially less because of the approximate 3-mile transition zone of marshlands, estuaries, and islands that separate Redwood Creek from the San Francisco Bay. Mitigation measures and zoning required by the Precise Plan alleviate potential risks of a tsunami or significant flooding, so there would be no impact to the project site from a tsunami. For example, the North Main Street Precise Plan requires that new development reconfigure top-of- bank areas to incorporate a creekside trail and wetland overlook areas. The trail is required to be 14 feet wide with a clear zone (i.e., no fencing) a minimum of 2 feet wide maintained adjacent to the trail and incorporate low-growing landscape materials. In addition, the Redwood City Zoning Code for Mixed-Use Neighborhood (MUN) District Zoning, Section 54.5-J specifies, “New development shall be subject to the requirements of Redwood City Stormwater Management and Discharge Control Program (Municipal Code Chapter 27A). In addition, new development shall maximize onsite stormwater management through landscaping and permeable pavement to the extent feasible (Ord. No. 1130-359, § 11(Exh. J), 4-8-13).” The Redwood City New General Plan Environmental Impact Report (City of Redwood City 2010), Appendix A, specifies Goal NR-5 to “Protect, restore, and maintain creeks and streams to ensure adequate water flow, prevent erosion, provide for viable riparian plant and wildlife habitat and, where appropriate, allow for recreation opportunities” through mitigation measure policies NR-5.1 through NR-5.7. Additional mitigation measure policies NR.7-1 through NR.7-3 reduce pollution from stormwater runoff.

Mudflow. A mudflow typically develops on steep slopes when water rapidly collects in the ground and results in a surge of water-soaked rock, earth, and debris. The California OES MyHazards database (http://myhazards.caloes.ca.gov) indicates that the project site is outside a mudflow zone based on its distance from the upland areas of the Coastal Range (Figure 4). So, there would be no impact to the project site from a mudflow.

References

AEI Consultants. 2016. “Phase I Environmental Site Assessment, (Market Rate) Redwood City 353-363 Main Street, Redwood City, San Mateo County, California 94063.” August 3.

California Emergency Management Agency. 2009. “Tsunami Inundation Map for Emergency Planning, State of California ~ County of San Mateo Redwood Point Quadrangle/Palo Alto Quadrangle.” June 15.

California Regional Water Quality Control Board, San Francisco Bay Region. 2015. Municipal Regional Stormwater Permit, NPDES No. CAS612008. Draft Findings. May 11.

_____. 2015 “San Francisco Bay Basin (Region 2) Water Quality Control Plan (Basin Plan)”. Incorporating all amendments approved by the Office of Administrative Law as of March 20, 2015.

CASGEM Basin Summary. 2014. Santa Clara Valley, San Mateo Plain, Basin Number: 2-9-03. May 30

City of Redwood City. 2008. “City of Redwood City North Main Street Precise Plan.” January.

_____. 2010. “A New General Plan for Redwood City, Final EIR.” August.

_____. 2016. “FY 2015/2016 Annual Report”. September 30.

_____. 2017. “City of Redwood City: Water Quality.” http://www.redwoodcity.org/departments/public-works/water/water-quality. February 24.

_____. 2017. “City of Redwood City: Zoning.” http://redwoodcity-ca.elaws.us/code/zo_art54

_____. 2017. City of Redwood City staff comments on draft “Water Quality Analysis Report for Residential Development Project at 353 Main Street, Redwood City, California”, received May 25.

DWR (California Department of Water Resources). 2004. “California’s Groundwater Bulleting 118. San Francisco Bay Hydrologic Region, Santa Clara Groundwater Basin, San Mateo Subbasin. Last update February 27.

EDR (Environmental Data Resources). 2017. “EDR NEPACheck® Main Street Apartments 353 Main Street Redwood City, CA 94063.” Inquiry Number: 4892132.1s. March 28.

EKI (Erler & Kalinowski, Inc.). 2016. “2015 Urban Water Management Plan for the City of Redwood City. June.

ESP (Earth Systems Pacific). 2016. “Geotechnical Engineering Study, Main Street Apartments, 353 Main Street, Redwood City, California.” November.

Metropolitan Planning Group. 2011. “Initial Study 333 N. Main St. Redwood City, California.” July.

OES (California Office of Emergency Services). 2017. MyHazards database http://myhazards.caloes.ca.gov. March 31.

Pampeyan, Earl H. 1992 “Geologic Map of the Montara Mountain and San Mateo 7-1/2’ Quadrangles, San Mateo County, California (To Accompany Map I-2390).” US. Department of the Interior, U.S. Geological Survey.