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The U.S. House of Representatives has passed H.R 2, which includes H.R. 919, Bird-safe Buildings Act. This bipartisan bill is designed to reduce bird mortality by calling for federal buildings to incorporate bird-safe building materials and design features. As many as one billion birds die annually by colliding with buildings in the United States.
— Read on www.constructionspecifier.com/house-passes-the-bird-safe-buildings-act/


July 1 is the data that laws go into effect in Florida.  Many times that are bills that are controversial or harmful.  From a utility perspective we have one that is more interesting to read   It deals with many things – blue green algae, regulation of septic tanks (a problem throughout the state), and sanitary sewer overflows, and increases fines to overflows (SB712/HB1343).  The latter makes utilities notice.  Basically, the bill is as a result of overflow flooding in Pinellas County several years ago.  Utilities must now report of efforts to reduce infiltration, inflow and overflows.  The bill does set up funds to help with the issue (50:50), but let’s look at what this means.

Substantial savings in operations can be achieved by reducing the amount of wastewater that must be pumped and treated. Utilities have long dealt with the infiltration and inflow (I and I) issues in their system by televising their pipes and identifying leak points, but this primarily addresses only the infiltration part of “I and I.”

Inflow, which creates hydraulic issues during rain events, leads to sanitary sewer overflows and can subject the utility to fines from regulatory agencies, and create publicity and legal issues when houses are damages from sewage backing up into houses and businesses. Where there are peaks in wastewater flows that match rainfall, inflow would appear to be a more likely candidate for the cause of the peaks than infiltration from pipes that are constantly under the water table.  As a result, dealing with the inflow portion of I and I is needed. Inflow often can be identified and corrected easily, and removing the inflow portion from I and I, often leads to a more focused plan for infiltration correction program. An inflow program will consist of the following:

  • Inspection of all sanitary sewer manholes for damage, leakage, or other problems
  • Repair of manhole walls in poor condition or exhibiting substantial leakage
  • Repair/sealing of chimneys in all manholes to reduce infiltration from the street during flooding events
  • Installation of dishes in all manholes to prevent infiltration
  • Installation of LDL® plugs where manholes in the public right-of-way or other portion of the utility’s system may be damaged
  • Smoke testing of sanitary sewer system
  • Identification of sewer system leaks, including those on private property (via location of smoke on private property)
  • Low flow inspection event (Midnight Run)
  • Documentation of all problems in a report to utility that identifies problem, location and recommended repair
  • GIS mapping of manholes and problem areas
  • Inspect the system for flow
  • Determine if flow is significant.

If flow exists, open consecutive manholes upstream to determine where flow is derived from. Generally, a 2 inch wide bead of water is a limit of “significant” infiltration.  The remainder is infiltration. Infiltration has a relationship between groundwater elevation values and flows which were developed using the Pearson product-moment correlation coefficient. This time the dependent value was the baseflow+infiltration and independent variable was the groundwater elevation. Since it was assumed that fluctuations in baseflow were negligible, any changes between baseflow+infiltration were assumed to be a result of fluctuations in infiltration. The first step is inspection of all sanitary sewer manholes for damage, leakage or other problems, which while seeming obvious, is often not the case. The manhole inspection documented condition, GPS location, ties to photographic data and some form of numbering if not currently available.

But televising lines does nothing for inflow -that is a surface issue.  So let’s start the effort to address inflow first – as this will help ensure the goals of this new law are met.

Call me if you need help or have questions 239-250-2423.


It has been at least 90 days for most of us dealing with altered realities with covid-19.  From a water industry perspective, while first responders, nurses and doctors are heroes in this fight with the virus, let’s not forget our water and wastewater staffs that ensure that the water and sewer needed by all the at-home workers and hospitals works like it should.  Social distancing when fixing a water or sewer leak is difficult, but the repair is necessary so our people do what needs to be done.  These complex systems continue to operate despite the threat posed by covid-19, and perhaps with increased threats associated with covid19 in wastewater.  We hear revenues are falling for local governments.  Let us hope that as cities and states see decreases in revenues in the general fund, water and sewer operations do not face budget cuts because of siphoning funds away to balance the general fund.  We don’t was to create more examples where utility funds are continually siphoned to other purposes at the cost of deferring needed investments.  Respect and thanks for our operations people doing their job is to give them the tools they need to keep us safe.  Let’s make that happen!


USEPA (2013) notes six basic steps to develop and implement a watershed master plan.  The first step is to build partnerships with surrounding communities.  Few communities can go alone to resolve such impacts.  For example, water may enter a community watershed from upstream and leave to impact another community downstream, overwhelming their system.

The second step is to characterize the watershed.  The process to accomplish this involves:

  • Identify land uses including vacant land, wetlands, etc.
  • Acquire soils data
  • Acquire topographic data (Lidar)
  • Identify relevant waterways
  • Identify basins for flood routing
  • Acquire FEMA flood maps
  • Identify storm of interest (25 year and 100 year for category 4 in the CRS manual)
  • Model flood response (Cascade)
  • Develop flood risk/hazard mapping
  • Identify areas of concern (repetitive loss)

Groundwater is relevant when the ground and surface waters are directly connected, and the soil lacks capacity for holding much infiltration. In addition, many plans are completed with the intent of improving water quality, thereby crossing paths with TMDL plans Note that USEPA recognizes the difficulty in obtaining watershed-related information with precision and acknowledges that a balanced approach is needed to address this concern.

There is a connection between WMPs and CRS. To earn CRS credit, communities must adopt regulatory standards that, at least, are creditable under element 452a Stormwater Management Regulations, require that runoff from all storms up to and including the 25-year event be managed, and ensure that future peak flows do not increase over current rates. In addition, coastal communities are required to evaluate the effects of sea level rise. Therefore, one strategy for reducing the effort associated with implementing this CRS element is working with neighboring communities that share watersheds. Working with other communities can help to maximize credits for the CRS element because of the way the impact adjustment is calculated. In addition, by working with neighboring communities, the cost associated with completing the hydrologic modeling necessary to earn credit for this element could be split.

Step 3 involves identifying measures to reduce impacts (watershed, regional, and local).  At the watershed level, this is difficult to do, but the ability to use collected data to drill down is useful.  Note that addressing local issues requires the ability to take the current data and drill down to details.  An example process that USEPA (2013) suggests for capital plans is:

  1. “Inventory existing management efforts in the watershed, taking into account local priorities and institutional drivers.
  2. Quantify the effectiveness of current management measures.
  3. Identify new management opportunities.
  4. Identify critical areas in the watershed where additional management efforts are needed.
  5. Identify possible management practices.
  6. Identify relative pollutant reduction efficiencies.
  7. Develop screening criteria to identify opportunities and constraints.
  8. Rank alternatives and develop candidate management opportunities.”

 

Item 1 above is generally completed through the following measures:

 

  • Review and evaluation of existing watershed data, including identification of features requiring immediate maintenance
  • Development of preliminary watershed model diagram
  • Establishment of GIS database for watershed resource features and parameter inventory through desktop and field reconnaissance

Floodplain analysis includes developing a watershed model and identifying associated inundation polygons. It builds upon information generated from the watershed evaluation so that planning and management decisions can be formulated. Floodplain analysis may include the following tasks:

  • Completion of the watershed resource feature and parameter inventory GIS database for the watershed using the acquired information
  • Assemblage of GIS database information into a specific format for a selected computer program which predicts the watershed’s response to the hydrologic cycle
  • Watershed model development, calibration, and verification
  • Floodplain delineation

Step 4 involves implementation, which means local communities participate in defining projects and solutions as well as the timing and means to fund them.  This is where many watershed plans fail – the ability to fund outside a jurisdiction is fraught with many difficulties.  Capital plans, bond issues, etc. are all part of the plan.

The final two steps are implementation and monitoring progress so that updates can be made.  USEPA recognizes that the processes involved in watershed assessment, planning, and management are iterative and that targeted actions might not result in complete success during the first or second cycle.

The reason this is relevant to water utilities was noted earlier – funds are needed, sourcewater protection is relevant to watershed plans and the results may impact your water supply.  Watershed planning occurs at a variety of levels of government – sometimes with consultants, other times via universities or regional agencies.  But in any case it is important to be involved in the process.

 


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Reducing flood risk is an ongoing challenge for local governments.  The National Flood Insurance Program (NFIP) has developed a means to assess flood risk and adjust flood insurance rates accordingly.  Many of these steps, developed as a part of the Community Rating System (CRS) are policy oriented.  That means local regulations, newsletters, outreach etc.  Getting more points involves capital programs which cost much more money, so many local officials try to balance the tradeoff of capital versus insurance reductions.  IT makes one wonder if the insurance loss might be a better means to assess, but that is a separate issue.

The development of capital projects means large amounts of water will be transferred from one point to another.  Most communities look at trying to get the water out of their community as fast as possible, but this can have downstream impacts (or if you are the recipient, impacts form upstream that you cannot control).  As a result, watershed plans are needed As a means to integrate local communities on a watershed basis.  Note a watershed is not local stormwater, so a stormwater master plan is not a watershed plan.  The watershed plan is a much larger effort, and one that normally included a means to fund basin-wide. Improvements.  The latter is why few true watershed plans actually exist, which impacts the ability of local communities to increase their ratings.

To address the watershed element, USEPA published the Handbook for Developing Watershed Plans to Restore and Protect our Waters in 2008 to provide users with a comprehensive resource to develop more effective watershed plans.  The goal was to improve and protect the nation’s water quality. However, the true benefit of watershed master plans extends well beyond this goal to include additional project opportunities that address water quality issues, low impact development, stream restoration, nature based park planning, mitigation banking, and conservation easements.  Specific objectives include:

  • Identify needs and opportunities related to flood risk, water quality issues, low impact development, stream restoration, mitigation banking, and conservation easements.
  • Develop and assess proposed projects to address the identified needs and preserve identified opportunities.

Note this extends well beyond water quantity, given that large volumes flushed in a watershed can have adverse quality impacts (think water supply which from which 60% of public users get their raw water supplies – the turbidity is a huge treatment problem).  In addition, plans are developed to inform using data-driven decision making using high-resolution data to create basin priorities, balance water quality, stormwater conveyance, and wildlife habitat program synergies and enable prudent spending of scare public funds.

According to the CRS Coordinator’s Manual, “the objective of watershed master planning is to provide the communities within a watershed with a tool they can use to make decisions that will reduce flooding from development on a watershed-wide basis.” Successful watershed master plans (www.floodsciencecenter.org) consists of:

  1. Evaluate the watershed’s runoff response from design storms of various magnitudes and durations under current and predicted future conditions,
  2. Assess the impacts of sea level rise and climate change,
  3. Identify wetlands and other natural areas throughout the watershed,
  4. Protect natural channels,
  5. Implement regulatory standards for new development such that peak flows and volumes are sufficiently controlled,
  6. Include specific mitigation recommendations that should be implemented in order to ensure that communities are resilient in the future, and
  7. Have a dedicated funding source like a stormwater utility in place in order to implement the mitigation strategies recommended by the plan.

One of the challenges is that watershed level planning crosses jurisdictional boundaries and are therefore challenging to get buy-in for.  If parts of the watershed are outside the community’s jurisdiction, coordination with the other communities is required. In addition, hydrologic modeling is required to determine the present and future runoff conditions. Not all communities will have an individual on staff that is capable of completing this kind of effort.

Part 2 of this blog will outline the planning process.

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