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HomeMy WebLinkAbout4. Neighborhood Drainage Program 02/10/2015Mount 6-1 Mount Prospect Public Works Department INTEROFFICE MEMORANDUM TO: ACTING VILLAGE MANAGER DAVE STRAHL FROM: VILLAGE ENGINEER DATE: FEBRUARY 2, 2015 SUBJECT: BACKYARD DRAINAGE PROGRAM: 7 -YEAR UPDATE A BRIEF HISTORY OF BACKYARD DRAINAGE ASSISTANCE IN MOUNT PROSPECT Numerous properties within the Village of Mount Prospect are prone to recurring overland flooding. This is substantiated by the numerous complaints that come to the Engineering Staff every year. While the flooding is obvious, the causes often aren't. 1 don't believe it was the intent of the original design for any properties to store stormwater in the yards. It should be noted that the standards for design have evolved over time. When many of the older areas of town were developed, the drainage standards were not as rigorous as our current Village ordinances which insure that proper drainage and stormwater management is provided for each newly developed site. Consequently, we do not experience this type of flooding in the yards of newer developments. While the current ordinances minimize the chance for occurrence of backyard flooding, previous drainage standards did not provide for sustainable drainage. Unfortunately many factors, both manmade (fences, landscaping, sheds, regrading, etc.) and natural (flat topography, soil conditions, settlement, etc.) can adversely impact the drainage of a property. But all backyard flooding sites share three (3) common elements: 1. Each of these sites accepts water from the naturally higher neighboring properties. 2. More water collects on these low properties than can be absorbed by the grass and landscaped areas. 3. No outlet exists to drain the ponding water. Originally, and consistent with most other municipalities, it was the Village's position that flooding problems occurring on private property were the property owner's issue to address. During the late 1980's, the Village adopted a policy to assist property owners by surveying the property, identifying the problem, and providing a design to the property owners to implement at no charge to the property owner. They could then obtain a permit, hire a contractor and have the improvements installed. Unfortunately, very few improvements were installed because of the cost of construction. During the 1990's, in an effort to further assist property owners address their flooding problems, the Village began sharing the construction costs. The Village still provided the survey and design, and also offered to reimburse the cost for work required within the public right of way; it remained the property owner's responsibility to hire the contractor and cover the cost of the Page 2 ... Backyard Drainage Program February 2, 2015 work on private property. Despite this offer to reimburse the property owner for roughly 50% of the cost for a typical design, less than 7.0% of all designs provided by Village Staff were implemented by the property owners. Recognizing that even the cost of the drainage improvements on private property was a greater burden than most property owners could afford, the Village implemented the Backyard Drainage Program (BDP). Before authorizing the BDP during a Committee of the Whole Meeting on May 13, 2008, the Village Board briefly considered requiring financial participation by the property owners, but ultimately it was decided before the contract was awarded for the first year of the BDP on June 2, 2009 that the Village would cover all construction costs, and would be responsible for the maintenance of that portion of the system in the public right of way (storm sewer, catch basin, and restrictor). The property owner is responsible for the maintenance of the system on private property (storm sewer, area drains, and rain garden). An agreement between the Village and the property owner is then recorded with the County which establishes the maintenance responsibilities for each party. To insure that the improvements installed remain functional and effective, a program has been developed under which the Village inspects the rain garden, grate, and pipe on private property every two years. THE CURRENT PROCESS Any resident experiencing backyard flooding is welcome to contact Public Works for assistance. Assistance is provided according to the following process: 1. Staff will consult with the resident to obtain a general scope of the problem. 2. Staff will perform a detailed survey of the site and adjacent properties as necessary. 3. Staff will provide a design to minimize the flooding on site. o If the flooding can be addressed by regrading the property, the property owner is provided the design and directed to obtain a permit and hire a contractor to implement the design. Correcting any deficiencies in the existing grading is considered as a site maintenance issue, so Village participation is limited to providing the design. o If the flooding cannot be addressed by regrading, the property owner is provided a design including a piped connection from a new inlet in the backyard to the receiving sewer. This connection includes a restrictor to minimize the impact of the stormwater on the receiving system. The property owner is always allowed and encouraged to install the design using their own contractor (at their own cost), but they are also eligible for participation in the Village's Backyard Drainage Program (BDP). Under the BDP, the Village will install the design as described previously. 4. Those sites eligible for participation in the BPD are placed on a list of all sites awaiting funding and construction. It is our intent to help those in most need first. To assist in determining which sites to address next, Staff has developed a system of evaluating each site, and assigning it a "Flood Index Number". Based upon the Flood Index Number, each site is then classified as "Flood Risk A", "Flood Risk B", or "Flood Risk C". Page 3 ... Backyard Drainage Program February 2, 2015 TYPICAL BACKYARD DRAINAGE PROGRAM DESIGN As no two backyards are exactly the same, so no two BDP designs are the same. Variables that impact the design include the size of the yard, obstructions in the yard and right of way (trees, garage, shed, pool, utilities, etc.), and the proximity to the receiving sewer. However, all designs share the following aspects in common: - All designs provide a release for stormwater that collects and stores in back yards. - A restrictor pipe is included which slows the rate of flow to the receiving system. - Installation of all designs can be accomplished with a minimum of disruption. - All designs minimize the amount of ongoing maintenance required. Following is a typical backyard drainage plan: Typical Private Property Improvements 160' — 6" PVC Pipe (Directional Bore) 40'— 6" PVC Pipe 1 — 12" Area Drain 1 — Cleanout 10 CY Rain Garden Soil Rain Garden Plantings (Installed under separate contract) Tvaically Public ROW Improvements 20'— 8" PVC pipe 14 CY Trench Backfill 1 — Connection to Existing Sewer 1 — 48" Catch Basin 1 — Restrictor 50 SF Sidewalk Restoration 15' Curb & Gutter Replacement 13 SY Pavement Restoration 20 SY Bituminous Driveway Restoration 19 SY Topsoil & Sod p ,W/ As�ux auxt •�RAt F r 42E.D9 =NY 9S 65 _>� "'^�+► ,. YrAt .S4 crani t', TiBi aB.3S3 rasa 7d.1;2 caFW/ H)R 9tl9d cmq W"A .4tl AR',-&" yy 00 PVC y Sb * " ENV paid j a8;:�iYF 4i8 -{H 5&01 90-94 Sd.dS 95.%F �q.G$ D& U) P9,01 yt MA, 4n. t awaaeF0x Yt£l a i 4/T� PA 635 i & •—sdi,3a 9f�IG!hE-1 F sol 4� - 5 i �fP�3 MEE PROIEC-%W RUWA..R RESMAOIX" SN Fgwxt(rw)� { ...m.. _....._...m ,r .� co, 5" --�F rxtl s ilRlWWAY REST RArXm FUJ 4F; . COO, SAINN (44' VX) W/ iM%tA vfoo (LSt:)laET3 W) 100A 7� 9.ax�A,rW4 ' tl 74D87 4,`bnVE:6'Y Sri . ALSARiVi N -x 19FSTGRAII:H --P E"f151#itl W*En i?Pi' 9F,¢3 � �1,•.•d° WAtEi Example ofof Design Installed throw hInstalled throw h the Backyard Backyard Drainage Program Typical Private Property Improvements 160' — 6" PVC Pipe (Directional Bore) 40'— 6" PVC Pipe 1 — 12" Area Drain 1 — Cleanout 10 CY Rain Garden Soil Rain Garden Plantings (Installed under separate contract) Tvaically Public ROW Improvements 20'— 8" PVC pipe 14 CY Trench Backfill 1 — Connection to Existing Sewer 1 — 48" Catch Basin 1 — Restrictor 50 SF Sidewalk Restoration 15' Curb & Gutter Replacement 13 SY Pavement Restoration 20 SY Bituminous Driveway Restoration 19 SY Topsoil & Sod Page 4 ... Backyard Drainage Program February 2, 2015 THE FLOOD INDEX NUMBER The factors contributing to the Flood Index Number only consider the most important aspects of the flooding: Does the water reach the house foundation? Does the water reach a detached garage? Or does the water just pond in the yard? Other less important and/or less quantifiable aspects such as depth, duration, and frequency of the flooding have not been included. In order to determine the Flood Risk Classification for a given site*, the total number of properties, sheds, detached garages, and homes reached by the floodwaters are tallied. The numeric values assigned to each is as follows: Each Home = 100 Each Detached Garage = 10 Each Shed = 2 Each Property = 1 *To avoid the necessity for easements and agreements between property owners, each design is typically confined to a single property, referred to as the "site". However, designs often benefit multiple properties as the ponding water. Thus, the Flood Index Number includes the impact to all properties served by a given design. As an example, the picture at the left clearly shows flood waters reaching two homes. Estimating the approximate water elevation, and comparing with the field survey, it is likely that the three neighboring properties behind these two also flood. These yards include two detached garages and two sheds not shown in the picture. The Flood Index Number for this site is: (2x100)+(2x10)+(2x2)+(5x1) =229 (House) (Garage) (Sheds) (Yards) It must be understood that the Flood Index Numbers are based on photos, aerial topography, our survey of the property, and anecdotal evidence provided by the property owners. We have sent out a questionaire to many of the property owners requesting assistance, but few have been returned. Consequently, the information used to determine the Flood Index Numbers and the resulting Flood Index Numbers is inconsistent, often exaggerated by the property owners, and subject to interpretation by Staff. Because of this, the Flood Index Numbers are subject to change, and are constantly being refined as new and more accurate information is received. THE FLOOD RISK CLASSIFICATIONS The values assigned to the elements considered in the Flood Index Number are designed to separate the various sites into different levels of risk, and are summarized below: Risk Level A: Properties in this category experience flooding that reaches the foundation of at least one house. (Flood Index Numbers > 99) Page 5 ... Backyard Drainage Program February 2, 2015 Risk Level B: Properties in this category experience flooding that reaches the foundation of at least one detached garage. (Flood Index Numbers 10 - 99) Risk Level C: Properties in this category experience flooding in the yard, and may impact one or more sheds. (Flood Index Numbers < 10) Utilizing this system, we have identified the following numbers of sites awaiting funding through the Backyard Drainage Program: Risk Level A: 24 Risk Level B: 38 Risk Level C: 80 OTHER MUNICIPALITIES' EXPERIENCES Most other neighboring communities experience the same backyard flooding problems that Mount Prospect does. And most other communities maintain the same position as that Mount Prospect originally held, that since the problem is on private property it is the owners responsibility and cost for any improvements. However, a few have developed programs to assist the property owners. • Arlington Heights indicated that they will construct a catchbasin in a back yard experiencing flooding with a connection to the storm sewer system if the property owner grants an easement. Following construction, the catch basin and pipe will be the maintenance responsibility of the Village. • Rolling Meadows indicated that they will have a similar program with the exception that all property owners that benefit from the improvements must share in up to 50% of the cost. They indicated that very few property owners are willing to participate. • The City of Des Plaines also began their program by paying for all construction, both on public and private property. Their program has since evolved to the point where the property owners are responsible for 25% of the total construction cost, with an upper Page 6 ... Backyard Drainage Program February 2, 2015 limit of $5,000. Their program covers designs similar to our own, as well as site regrading. (It is Mount Prospect's position that regrading is site maintenance, and so is the property owner's responsibility, even though we will still assist by performing a survey and providing a design at no cost to the property owner.) Des Plaines also allows payment in either a lump sum, or by taking out a 10 year loan at 5% interest. CURRENT PROGRAM FUNDING When the Village Board first established the Backyard Drainage Program in 2008 a funding source was identified as a Fee in Lieu of constructing stormwater improvements. Many site improvement projects are too small to provide meaningful stormwater management. These projects are typically less than 1.0 acres, but still generate stormwater runoff. It was determined that a fee would be charged for these smaller sites instead of trying to provide stormwater detention. This fee is based upon the amount of impervious surface created: Commercial/Industrial/Multi-Family: $2.00/sf new impervious surface Single Family Residential: $0.50/sf new impervious surface This fee was collected with the intent of funding the Backyard Drainage Program. In 2007, the first year of the fee, $90,577.00 was collected. Unfortunately, this fee is tied to development, so as development has slowed over the past several years, the amount collected has dwindled significantly. Less than $10,000 has been collected over each of the past several years. Consequently, the funding for the BDP has had to been augmented by other sources whenever possible. This has led to inconsistent funding over the years, including 2010 and 2012 when no funding was available and no improvements were installed. Based upon 2014 construction costs, we estimate the total cost of construction for our previous example site to be $26,115.00. Of this, $10,255.00 is for construction within the public right of way; the remaining $15,860.00 is for construction on private property. At the current rate of funding, $100,000 per year, it will take approximately 37 years to complete all the sites on the current list. FUNDING OPTIONS Although the original decision was to not require homeowner participation in the cost of the Backyard Drainage Program, Staff has explored several different ways the construction costs could be shared, including a flat rate, percentage, paying for specific items (i.e., restoration), or some combination thereof. Since the previous attempt at sharing the cost provided negligible results and since other communities have had similar experiences, Staff is hesitant to conclude that another cost share program would provide significantly better results. However recognizing the time period to complete the projects currently on the list, and being aware that new requests are received every year, Staff would like to discuss the following funding options, which figure in the same funding rate of $100,000 per year: 1. Property Owner Maximum $5,000 Similar to Des Plaines, this option would require the property owner to contribute up to a maximum of $5,000. This would reduce the time to complete the current list to 30 years. Page 7 ... Backyard Drainage Program February 2, 2015 2. 50 — 50 Option The cost of the improvements are split equally between the resident and the Village, approximately $13,000 each. This results in cutting in half the time to complete the current list about 19 years. 3. Public — Private Option The property owner pays for the work on private property, approximately $16,000 and the Village pays for the work within the public right-of-way, approximately $10,000. This results in completing the current program in about 15 years. 4. Risk Level A Focus Option In this option the Village would continue to pay for 100% of cost for locations in Risk Level A, the most critical sites where overland flow can affect houses. These 24 sites could be completed in 7 years. At that time Staff could return to discuss the remaining sites with the Village Board. The intended source of funding, fee in lieu, does not have sufficient capacity to fund any of these options. All of this funding would likely be derived from the general fund. Furthermore, the ability of the general fund to support capital projects of this type will vary annually. SHARE COST OPTIONS DISCUSSION If Village funding levels cannot be increased above the current level, then the Village Board may wish to consider some sort of cost share option to provide flood relief for these properties in a more reasonable time frame. Unfortunately these are the likely hurdles that will be necessary to navigate over in order to accomplish the goals of the program: 1. As has been our past experience, requiring the property owner to pay for the cost of the work on private property would virtually eliminate participation in the program, leaving many areas to continue flooding. 2. Many of the property owners suffering from severe and recurring flooding problems are unable to contribute any meaningful amount. However, neither the cost of the particular improvement, nor the ability to participate relates to the severity of the flooding problem on a given property. Consequently, requiring participation could cause the Village to pass over an owner in greater need that has no means to participate in favor of an owner with a lesser need but a better financial situation. 3. In most cases, the design installed is confined to a single property, but benefits several properties. It is unrealistic to expect participation from the neighboring properties benefiting from the work, and yet it seems unfair to require only one of the benefiting owners to participate in the cost. 4. The current program requires no financial participation by the property owners. This has been communicated to the property owners that have requested drainage assistance to date. If we now change the program to require their participation, we can expect considerable backlash, especially from those still awaiting assistance that may know a property owner that we have already helped. Page 8 ... Backyard Drainage Program February 2, 2015 REQUEST FOR DIRECTION • Should the Village continue to participate in the cost of constructing Backyard Drainage Program Improvements? • How should Backyard Drainage Program Improvements be funded? (Options 1, 2, 3, 4 or other) • What should the source of funds be for Village expenditures related to the Backyard Drainage Program Improvements? The sites that have been completed to date have provided great benefits to the properties and have received positive comments from those involved. In order to keep the program moving forward, now is the time to discuss the funding options with the Village Board. Village Staff will be available for the February 10, 2015 Committee of the Whole Meeting to lead the Board in such discussion. ► I concur with this rrt. Public Works Director Sean P. Dorsey H:\Engineering\Drainage\Backyard Drainage Program\COW Meeting 2-10-2015\Staff Report