City of Oak Harbor LID Blog: 2009

Thursday, November 5, 2009

Project Description

Thanks for viewing the City of Oak Harbor's LID blog. This post gives a brief background of the project, information on events happening in Oak Harbor related to LID, informational resources (links to other websites and reports), and pictures of LID applications in Oak Harbor and elsewhere.

The host of this blog is Ethan Spoo, Senior Planner with the City of Oak Harbor. I am also the City's project manager for the LID code update. Feel free to tell me how I can make this blog better or ask me questions about LID. And most of all, enjoy the blog!

Late in 2007, the City applied to receive technical assistance from the Puget Sound Partnership (PSP) to help integrate LID standards into the Code. After being selected as one of the 13 Puget Sound jurisdictions to receive assistance, Oak Harbor met with PSP’s consultant, AHBL, several times during 2008. Coupeville was also selected. AHBL helped the City identify areas where LID standards could be integrated into the Code and drafted proposed LID language. The sections of the Code reviewed by AHBL were: (1) Chapter 11.17 – Street Design Standards (2) Title 12 – Stormwater (3) Title 19 – Zoning (4) Title 21 – Subdivisions and, (5) Engineering Standard Detail

Staff have reviewed the draft code and have identified policy issues which need to be considered by the Planning Comission before the code is released for public review. The policy issues and the discussion around them will be a central part of this blog.

Examples of LID

Residential Rain Garden

This is an example of a rain garden which has been built into someone's front yard.

Pacific Crest Bio-retention Area

This is an example of a bio-retention area in the Pacific Crest Development in Oak Harbor. The bioretention area allows stormwater from the adjacent road to infiltrate into the soil thereby filtering pollutants out of the stormwater.

Harbor Station Rain Garden

This is an example of a rain garden at the Harbor Station develompent in Oak Harbor. The rain garden filters stormwater from the parking lot.

Island Place Grass Pavers

This picture shows grass pavers at the Island Place development in Oak Harbor. The grass pavers are a hard plastic, honeycomb grid which allows grass to grow between the spaces, but still supports the weight of vehicles.

Bio-retention Area

This is another example of a bio-retention area along a public street. Stormwater enters the bioretention area via the inlet in the middle of the picture.

How a Bioretention Area Works

A bio retention area also known as a rain garden is a planted depression that allows rainwater runoff from impervious urban areas like roofs, driveways, walkways, and compacted lawn areas the opportunity to be absorbed. This reduces rain runoff by allowing stormwater to soak into the ground (as opposed to flowing into storm drains and surface waters which causes erosion, water pollution, flooding, and diminished groundwater). Rain gardens can cut down on the amount of pollution reaching creeks and streams by up to 30%.

Native plants are recommended for rain gardens because they generally don't require fertilizer and are more tolerant of one’s local climate, soil, and water conditions. The plants — a selection of wetland edge vegetation, such as wildflowers, sedges, rushes, ferns, shrubs and small trees — take up excess water flowing into the rain garden. Water filters through soil layers before entering the groundwater system. Root systems enhance infiltration, moisture redistribution, and diverse microbial populations involved in biofiltration. Also, through the process of transpiration, rain garden plants return water vapor into the atmosphere. A more wide-ranging definition covers all the possible elements that can be used to capture, channel, divert, and make the most of the natural rain and snow that falls on a property. The whole garden can become a rain garden, and all of the individual elements that we deal with in detail are either components of it, or are small-scale rain gardens in themselves. Source: http://en.wikipedia.org/wiki/Rain_garden

Policy Issues

The following policy issues are currently being discussed by the Planning Commission:

(1) Should the City place limits on the amount of impervious surface in new developments?

(2) Should impervious limits be voluntary, incentive-based, or mandatory?

(3) Should LID streets be voluntary, incentive-based, or mandatory in new developments?

(4) Should LID parking facilities be voluntary, incentive-based, or mandatory?

(5) Should the City consider setting parking maximums for non-residential uses, i.e. putting a limit on the number of parking spaces for commercial, industrial, and office uses?

For more information on each of these issues, please see the blog post dated March 3, 2010.

Events

Standing Committees: no meetings to discuss LID topics are scheduled at this time.

Planning Commission:

March 23, 2010 @ 7:30 p.m. LID - Parking Maximum Standards (see memo below dated 3-18-2010).
Staff will discuss LID parking maximum standards and requests input and guidance from the Planning Commission and public.

February 23, 2010 @ 7:30 p.m. LID Code Project Update (see memo below dated 2-11-2010).
Staff will discuss LID practices for streets, parking facilities, and coverage limits. Staff requests input and guidance on each practice from the Planning Commission and public.

January 26, 2010 @ 7:30 p.m. Introduction to the Draft LID Code (see memo below dated 1-21-10attached).
Staff will introduce the draft LID code to the Planning Commission and give an overview of the specific LID practices within the code. In February, Planning Commission will begin discussions on each specific LID practice.
LIDMemoMarch-3-15-10

LID-Memo-2-11-10

LID-Memo-1-21-10

LIDIntroMemo-11-4-09

City Council: no meetings to discuss LID topics are scheduled at this time.

Tentative Schedule

The City will begin the LID code update by holding a series of public meetings at Planning Commission to get input from the community, developers and business owners. It is then anticipated that staff will incorporate the Planning Commission's and public comments into the draft code. Staff will then present Planning Commission and the public with the code during summer of 2010. Planning Commission will consider the code and then forward a recommendation to City Council for their consideration. This schedule is tentative and is subject to change in response to public input, requests for further study, or scheduling conflicts.

Nov '09-April '10 - Public Meetings
April '10-June '10 - Staff Drafts Code
July '10-Aug '10 - Draft Code Released to Public, Public Meetings, Planning Commission Consideration
Sept '10-Oct '10-City Council Consideration

Want More Information?

If you want more information on the background of the project than is provided here, please view the "Update Memo-2-13-09" attached to this post. That memo was sent to the Oak Harbor Planning Commission on February 13, 2009 and was presented to them at their March 17, 2009 meeting. You may also want to look at the Powerpoint presentation which was presented to Planning Commission on March 17 and is also attached to this post.

Update Memo 2-13-09 Update Presentation

Resources

The following are helpful web and print resources. I have tried to limit the resources to the highest-quality ones covering a variety of LID topics.

Web Resources:

http://www.lid-stormwater.net/index.html . This site has been developed through a Cooperative Assistance Agreement under the US EPA Office of Water 104b(3) Program. The site is intended to give planners, engineers assistance in designing and managing LID systems. Be sure and visit the "Start Design" and "Typical Landscapes" tabs.

http://www.epa.gov/nps/lid/ . The US Environmental Protection agencies website on LID with links to studies, design manuals and even more websites.

www.lowimpactdevelopment.org/. The Low Impact Development Center is a non-profit organization dedicated to the advancement of Low Impact Development technology.

Helpful Documents:

http://www.psp.wa.gov/downloads/LID/LID_manual2005.pdf . This document is a manual produced by the Puget Sound Action team and Washington State University which discusses different LID techniques and physical designs.

Economics of LID:

http://www.econw.com/reports/ECONorthwest_Low-Impact-Development-Economics-Literature-Review.pdf . This document is a literature review of the economic benefits of LID by an economic consulting firm (ECONorthwest).

http://www.lowimpactdevelopment.org/lidphase2/pubs/LMI%20LID%20Report.pdf . This document discusses the development, construction, and maintenance costs of LID.

What is Low Impact Development?

This post describes what LID is. For more information and descriptions of LID, please visit the "Resources" section of this blog in the right-hand side bar.

LID is an environmentally-friendly way to treat stormwater water runoff. Conventional stormwater systems typically collect rain water runoff from buildings, sidewalks, driveways, and roads. The runoff from these "impervious" surfaces is commonly polluted with oil, pet waste, and other suspended solids which come from peoples cars, houses and other buildings. The system then conveys runoff in pipes to a storage and / or treatment area, which is very commonly a pond or an underground vault. Finally, the stormwater enters the public storm system, where it outfalls into a river, lake or the ocean. Oak Harbor's stormwater oufalls into the Harbor near Windjammer Park. Although the stormwater is treated prior to release in to Oak Harbor, many of the pollutants make it past the treatment systems and are released in Oak Harbor. Aquatic life has a difficult time surviving in these polluted waters. Sometimes, these pollutants make their way back into drinking water supplies and some studies have documented negative effects on humans.

LID techniques take a different approach to stormwater collection and treatment. As opposed to piping the runoff and collecting it at a central location, LID seeks to mimic a sites natural hydrology. This means runoff is filtered in grassy swales, vegetative buffers or pervious pavements which treat the water. Much of the water than inflitrates or percolates into the ground near where it falls, instead of being piped into a public stormwater system and released into Oak Harbor. LID provides better filtration and treatment of stormwater. In general, LID techniques focus on reducing or even eliminating impervious surfaces that are the leading way pollution travels into Oak Harbor. Thus, leaving trees on a site (instead of chopping them down) is one LID technique.

LID techniques can have financial advantages for developers and property owners. In some cases, LID techniques cost less to install than conventional methods, in addition to providing better treatment. As an example, one LID technique (narrowed street widths) reduces the amount of pavement needed to build a street. Less pavement means less asphalt and less cost for the developer. LID techniques can also allow developers to reduce the size of or eliminate stormwater ponds. The land, which was otherwise devoted to stormwater ponds, can then be used for other purposes, such as new buildings. Attached to this blog are pictures showing examples of LID techniques already in use in Oak Harbor.

There are literally dozens of LID and conventional stormwater treatment techniques. LID does not save the developer money in every case, so it does not always make financial sense to use LID. Financial benefits of LID are usually realized on a case-by-case basis, depending upon the existing conditions on a site (i.e., whether a site's soils allow for water to infiltrate), and the array of LID technologies available to a developer.

City of Oak Harbor LID Blog